Cadet/Castle components sources and substitutions

Category: Unknown · Tags: cadet, castle · Posts: 184

#1 — creatorlars · 2018-07-17

1. You can substitute LT1256 for LT1251 in any of the Cadet designs
2. At LZX we have sourced LT1256 in the past from Mouser and directly from Linear Technology/Analog Devices.

#2 — Robbertunist · 2018-07-22

Hello everyone

Is there a thread on here specifically for questions about the components required for the DIY cadet series? I typed “Cadet” into the search this seemed like the most relevant thread.

I’ve a couple of simple questions. My first, is there such a major difference between a 2n3904 and the 2N3904BU that I should definitely only use the BU version? (Same for the 2906).

Pretty much the same question for the TL431BQLPM and a TL431 or the TL431a, my local store stocks the last two but not the BQLPM variety.I did quite a bit of reading through the datasheets of the ATMEGA88A-PU and the ATMEGA88 to see their exact difference, (I’d include a couple of screenshots I took but I can’t attach them here for some reason). The Atmel ATmega48A has an operating voltage range of 1.8V - 5.0V and the Atmel ATmega48 has an operating voltage range of 2.7V - 5.5V.

Thanks for any help, tips, suggestions and explanations, Robin in Berlin

PS. I’ll be on holiday for 3 days as of tomorrow.

#3 — creatorlars · 2018-07-22

Hi Robin!

We can use this thread for those questions, I’ll change the title.

1. 2N3904 and 2N3906 is OK. These are generic NPN/PNP parts.
2. TL431 variants, check the datasheet to make sure the pinout is the same as the one specified. Some of the variations have different pinouts. If pinout matches it should be okay. LM4040 is another substitute. These are all 2.5V precision voltage reference parts.
3. I believe the source code will need to be adjusted and recompiled if you wanted to use a part other than ATMEGA88A, so that’s not an option. Are you having trouble sourcing this one? We ship all PCB+Panel sets with a pre-programmed ATMEGA88A.

#4 — creatorlars · 2018-07-22

#5 — JunkRhythm · 2018-07-24

Here’s a few alternate toggle switches with shorter bat style levers. All of these will require hand wiring.

108-1MD1T2B3M1QE-EVX DPDT ON-ON 108-1MS1T2B3M1QE-EVX SPDT ON-ON 108-1MS3T2B3M1QE-EVX SPDT ON-OFF-ON

#6 — Robbertunist · 2018-07-27

Hello and thanks for your informative reply @creatorlars

Regarding the ATMEGA88A, I think the seller has missed placed it. It shouldn’t be a problem thankfully.

Talk soon, Robin

#7 — Robbertunist · 2018-08-01

Robbertunist wrote:

TL431BQLPM and a TL431 or the TL431a

I did quite some reading but it was quite clear that the BQL version has a much higher temperature tolerance, as much as 125 degrees Celcius if I’m not mistaken. The regular version and the ACL I found could only stay steady till 70 degrees C. Do modules like the LZX cadet range generally operate at higher than 70 degrees?

#8 — creatorlars · 2018-08-01

No, they don’t run hotter than 70 degrees C. More like 40-50 C at the most. The higher temperature parts are rated for automotive or industrial use, but there’s no problem with using them.

#9 — Robbertunist · 2018-08-02

Thanks Lars for the temperature explanation

I guess it’s the power supplies where all the heat is generated and given off.

#10 — creatorlars · 2018-08-02

Not always – voltage regulators at the inputs of modules and some of the higher current ICs can sometimes generate heat as well. Nothing in the system ever gets hot enough to need high temperature rated ICs though. If you’re wondering why I picked the original partnumber I did, it’s probably because that part had good stock levels and a better price when I originally selected parts for the BOM. Even though there are many possible variants and alternate parts, I always prefer to list a very specific part to avoid confusion. Learning when and how to substitute is part of the learning experience I hope building these DIY modules will provide!

#11 — JunkRhythm · 2018-08-09

If anyone is looking for decent pricing on LT1256 ICs, check out Arrow Electronics. They have them for $7.33 and if you are a new customer, you’ll get 30% off your first order. Wait, it gets better. Free FedEx shipping!

So far I’ve placed two orders through them and shipping from The Netherlands to California was faster than from Mouser to Los Angeles.

#12 — microtonal · 2018-10-14

crossposting from the switch thread since this one is a sticky…

The following E-Switch parts are drop in replacements for the Mountain Switches specified in the Cadet BOMs. Note that like the original SPDT, the below SPDT has right angle legs too short to reach the PCB holes and you’ll need to use some extra wires such as resistor leg cutoffs to splice them in.

These parts are also quite a bit cheaper than the originals or many substitutes.

SPDT, right angle, non-threaded bushing, short toggle, part no. 100SP1T2B4M6QE, $3.32/1 piece https://www.mouser.com/ProductDetail/e-switch/100sp1t2b4m6qe/?qs=rR7wk9eDIwq%2bdlBXTZsQkg%3D%3D&countrycode=US¤cycode=USD

DPDT, right angle, non-threaded bushing, short toggle, part no. 100DP1T2B4M6QE, $4.21/1 piece https://www.mouser.com/ProductDetail/e-switch/100dp1t2b4m6qe/?qs=ah0KxwAvRCEz9RyQvbJXcw%3D%3D&countrycode=US¤cycode=USD

#13 — reverselandfill · 2018-10-14

as a tip: you can get free LT1256 / LT1251 samples from Linear Technologies.

I think the maximum is 2 of each. They also have other interesting IC’s, so get those too

#14 — Agawell · 2018-10-26

just tried to get the LT1251 sample from Linear Technologies - you need a business email (which I don’t have ) to get them!!!

#15 — joem · 2018-10-27

I noticed that when I got a sample. I felt a little funny telling them that I needed two LT1251’s for my job at a book store, but they sent them anyway!

#16 — creatorlars · 2018-10-27

Don’t feel bad about taking them up on those free ICs. I used to get them and now we buy 1000-2000 at a time sometimes! Shapechanger alone has 8!

#17 — Robbertunist · 2018-11-15

Thanks JunkRhythm for posting the link to Arrow Electronics

#18 — JunkRhythm · 2018-11-15

No problem, it’s a good deal that needed to be shared.

#19 — o2w · 2018-11-26

Hi, Can anyone help me with options to substitute some of the components for the Cadet. I ordered all that was available on mouser a few months ago, and still there are missing some parts. Also I am not in the U.S so can’t use Analog Devices to get replacement for some parts…

So in need for:

10TF230

TL431BQLPR (couldn’t find replacements as suggested above)

MF1/4DCT52R1003F2

7201MD9ABE

Thank you!!!

#20 — Agawell · 2018-11-26

I just built a multiplier, a processor, a scaler and a vco and 4 castle modules - these were my 3rd to 10th builds - scaler works for definite - still waiting on an ordered visual cortex to test the others - but all but one get power in the case and don’t blow anything else up which is a good start - I did screw one of the castles up which will be build 10 when a new pcb arrives from thonk - next of these will be the castle adc and dac and a sync gen (one of the parts for this is difficult to find*) - but anyway:

for the switches you’ll need to find one of the replacements above - I found some cheap ones on tadya - but not tried them yet - most of the replacements don’t drop in - you’ll have to solder bits of resistor wire to the legs of the switch and to the PCBs (really easy btw) - I got mouser part 611-7201-051 as a direct replacement for the 7201MD9ABE, but it is very expensive - also watch out for the length of throw of the switch - ie how long the lever is - i accidentally got a mixed bag - all the ones I found on tadya (took like 3 mins) had the same short levers so I’m going to go with those in future - you could also try thonk - they have some switches that might work but again will need bridging with wire

I got a TL4331A from mouser - part no 863-TL431AILPRAG just check the data sheet that they are the same

mouser offered a suggestion to replace the 1003 resistor with something else - this one i think - 71-CPF1100K00FKEE6 - just check that the datasheets match

I did get 1 part from arrow - free shipping and no minimum order - LT1251CN#PBF but quite expensive compared to getting samples if you can

if you are only missing a few parts don’t buy from mouser - they charge a lot for shipping unless you’re buying enough to qualify for free shipping (50€ here)

tadya are pretty cheap too, but they have a minimum order (5€) and charge shipping, but it was cheap and not horrifically slow

*R13 - 1623934-1- is only available from mouser on a roil of 40000 for 40€ - I found them at tadya for something like 2 cents each - minimum order 10 - so bought those

#21 — reverselandfill · 2018-11-26

o2w wrote:

10TF230>>>> TL431BQLPR (couldn’t find replacements as suggested below)>>>> MF1/4DCT52R1003F2>>>> 7201MD9ABE>>>> Thank you!!!

hi 02w

I have all these in my box of videoparts.

(the toggle switches I have are the substitutes listed above. the normal types that you have to wire)

where are you located? I’m in NL (eu)

I can send you the missing parts

#22 — o2w · 2018-11-27

WOW!! That would be amazing! Thank you!

But I’m in Tel Aviv

How can we make it work and how can I pay you?

Cheers!

#23 — o2w · 2018-11-28

Hi thank you! Good luck with the new castle! I also messed one up but hope these ones will work!

I will check all those replacements. that’s a great help!

#24 — pbalj · 2018-11-28

Can I ask what messed up?

#25 — Agawell · 2018-11-28

Hi Phil

Thanks for asking!!

mine was due to tiredness and inexperience - it was my fourth or fifth diy module ever - 2nd without a detailed build document - never soldered anything before - only learnt from youtube and dutch modular fest - which was semi-supervised - and everything else had worked fine first time

I had 2 packs of resistors (which looked almost identical) on the desk picked the wrong one up accidentally and stuffed and soldered them all in before noticing that they were the wrong ones + bad attempt at de-soldering with a cheap de-soldering pump and a later first attempt with braid => frustration and a slightly beat up board with some scorch marks and scratches

at the end of the day i learnt the obvious:

double check what you are placing where, and check again before you actually
solder

don't build after midnight

it’ll have cost me less than 20€ - so annoying but not the end of the world - ordering a new pcb from thonk today to take advantage of the free shipping

I’ve built a further 4 or 5 modules since and they have all at least powered up ok - will be testing imminently once I’ve got my head fully round my new Visual Cortex - which I’m having a few issues syncing - but again most of that was late at night

#26 — o2w · 2018-11-29

Agawell wrote:

double check what you are placing where, and check again before you actually solder don’t build after midnight

Definitely got to the same conclusion

the Cadet is my first soldering project ever…

Was super late at night, over enthusiastic I placed the wrong part, and when pumped it out, lifted a pad … nothing to write home about but well yeah - work slow

#27 — gosseyn · 2019-06-02

Hi,

Are MLCC capacitors absolutely necessary ? Or can I use ceramic disc ones ?

Sorry if that’s a stupid question but I couldn’t find a simple answer and I’m relatively new to DIY.

Thanks !

#28 — Agawell · 2019-06-03

I should think as long as the rest of the specs are the same - ie capacitance, tolerance, size, etc then you should be ok

just check the data sheets to confirm

#29 — sean · 2019-07-06

Is sourcing some LM6172IN Op Amps on Ebay an especially bad idea?

They’re back-ordered at Mouser anyway right now, and about 1/3 as much from China.

#30 — JunkRhythm · 2019-07-06

In stock at https://www.digikey.com/product-detail/en/texas-instruments/LM6172IN%2FNOPB/LM6172IN%2FNOPB-ND/364218 without the worries.

#31 — reverselandfill · 2019-07-06

I recently bought a testbatch on ebay - they worked fine.

yesterday I ordered more from them. hopefully they also work

seller: (deleted link to avoid sadness) for reference: ‘allenlu1995’

update: I got some fakes with this seller. so avoid!

#32 — JonasBers · 2019-07-06

Re: disc caps — I’m no expert by any means, but I’ve heard that ceramic discs can be microphonic at high frequencies. I always try to implement best practice with video stuff because of all the weird voodoo like that. It’s one of those things that’s probably fine, but I like to eliminate any possibility of letting the circuit act weird, however infinitesimal.

#33 — JonasBers · 2019-07-06

I should elaborate — a significant part of this has to do with troubleshooting, so if something’s gone wonky, I don’t have to think, “oh is it those goddamned capacitors I spent 1¢ on instead of 2¢ ?!” and then I can just simply focus on plugging the power connector in all the way, or whatever was the actual problem.

#34 — sean · 2019-07-24

Following up on this… I ended up trying some of the Chinese LM6172INs off of Ebay. And, as reverselandfill mentioned on another thread, there is some blurring (presumably because they aren’t actually as fast as they need to be?). Not recommended.

Figured this info could be helpful here if someone is searching in the future. It’s a shame because they are 1/3 the cost.

#35 — reverselandfill · 2019-07-24

see here

Hey > There was some interest in doing a groupbuy for LM6172 IC’s > If we can get to 250 or 500 pieces, it will become interesting. > If you ordered a pcb (set) of the Triple Function Generator with me, > I can send them along without extra cost. > If not, I don’t know if the shipping cost will be too much  - this will depend on how much IC’s you want. the weight… > Best option is Mouser, because they pay the taxes & shipping > Mouser price breaks: >>>>> [1:]> € 4,23>>>>> [10:]> € 3,80>>> [100:]> € 3,11>>> [2…>

#36 — reverselandfill · 2019-07-24

I also filed a refund with that certain seller. so should you!

update: I just got the full amount in return via paypal.

#37 — sean · 2019-07-28

Same. And (not surprisingly) no request to actually return them.

Going to just enjoy some glitchy/smudgy ICs until the bulk order of the real deal happens.

#38 — GijsvO · 2019-10-17

How critical is the 100ppm specification for the 100k resistors in the Cadet series? I’m currently working on the Cadet II and soldered normal 100k 1% resistors in place of the 100ppm ones. Will this cause problems?

#39 — creatorlars · 2019-10-17

No problems. Standard 1% resistors are fine.

#40 — pbalj · 2019-10-17

Can you write down any markings on those 6172s here? My fakeys say JR64AC. I’m wondering if they’re all the same marking.

#41 — sean · 2019-10-17

Mine are M732F…

#42 — VisibleSignals · 2019-10-23

Hey guys,

LT1251 and LT1256 (DIP) seem to have nearly doubled in price in the past year or so, and the best price I can find now is USD$13.50 or more per each (Arrow, link above from Aug 2018).

I need a few for some Cadet builds - does anyone have a secret source they’re willing to share? No dodgy ebay seller links please, unless you vouch for them personally :-\

For reference, I tried soldering an SOIC LT1256 into a dip socket, using tiny wires, and it was no fun whatsoever and took over an hour… so not something I’d recommend

Thanks!

#43 — rempesm · 2019-10-24

It’s possible to get 2x of each as a free sample from Analog Electronics: https://www.analog.com/en/products/lt1251.html#product-samplebuy

#44 — reverselandfill · 2019-10-24

don’t forget to get samples of both TH and SMD . of all interesting IC’s they have!

(better make the most of the free samples, I mean)

#45 — reverselandfill · 2019-11-20

I’m building some more Cadet modules (for somebody else) and am wondering if I should use IC sockets.

#46 — JunkRhythm · 2019-11-20

I never use IC sockets anymore.

#47 — reverselandfill · 2019-11-20

why not? interference?

#48 — JunkRhythm · 2019-11-20

I originally read about possible interference so that was part of my reasoning. My other reasoning is that I had stopped using them for audio DIY years prior so I went with consistency on my builds. I see it as fewer parts to inventory, fewer parts to fiddle with and a reduced opportunity for errors on my end as well as for the end user. With SMD being so widespread and the lack of need to use sockets for SMD ICs, I figured it’s an old habit that doesn’t really need to continue for me. In my experience, I haven’t needed to replace ICs and in those cases it’s never been that hard to de-solder and replace.

#49 — reverselandfill · 2019-11-22

I go for socketless , I think. It feels weird though. shoes without socks

The ATMEL IC gets a socket. just in case…

#50 — VisibleSignals · 2019-12-11

FYI I posted about component substitutions (BS170, 15uF MLCC) for the Cadet IV Ramps DIY module here: Cadet IV Ramps uncommon component substitutions

#51 — fulhjort · 2020-01-21

About to order parts for the Scaler and my best option so far doesn’t have the 0R resistor, but it does have a 0.1R resistor, will it work regardless? I would order from Mouser, but I really don’t want to spend 20 euros on shipping (orders over 50 euros are free, and I’m barely over 10 euros…).

#52 — VisibleSignals · 2020-01-22

A 0R resistor is a piece of wire with no resistance, so you can cut the leg off a resistor or other component and use that instead

0.1R will also be just fine.

#53 — Agawell · 2020-01-22

The trick is to order a number of modules worth of parts at once - so you get over the 50€ - actually works out at 60€ as that is pre VAT price

#54 — fulhjort · 2020-01-22

Yeah, I’ve done that before, but I don’t currently have any other plans except for stuff I already have on my table.

#55 — Agawell · 2020-01-22

Yeah been there… I’ve got a couple of modules awaiting side adjustable trimmers… and nothing else in the pipeline… so they can wait a bit longer until there’s something else I need…

#56 — VisibleSignals · 2020-01-22

Some of us in the city where I live get together occasionally to pool our orders and share the postage costs. But obviously that only works if you know others nearby!

#57 — fulhjort · 2020-01-23

Yeah, a friend needed something so he got in on the order, but the shipping from that place was only 2,9 euro regardless. Sadly they were out of TL072’s, but a guy on forum was able to hook me up :D.

#58 — VisibleSignals · 2020-01-23

TL072 should be common enough that your local bricks and mortar store stock them.

#59 — fulhjort · 2020-01-23

The two stores in town have some resistor packs but that’s about it.

#60 — VisibleSignals · 2020-01-23

That’s crap, sorry

#61 — dubpixel · 2020-02-05

Hi all -

I feel a bit silly asking this question but I am new to eurorack modules and building any sort of DIY video module. Just making sure i get my head around whats what, before i buy parts for cadet 1-3…

I have experience designing and fabricating boards for LED control and other applications - so not a parts noob, but here i am.

the futurlec parts - specifically:

IDCMH16

IDCMH14

HEADD6

seem like there could be an easy sub from mouser - so i ask: why specifically them?

also the thonk parts? - there is no reccomended US vendor (seems like BLMS could have the knobs??)?

just trying to optimize purchasing.

TIA

_JF

#62 — VisibleSignals · 2020-02-05

Hi @dubpixel. Your question seems perfectly reasonable to me. I don’t see any reason to be fussy with those connectors - it’s probably just coincidence that LZX bought a large batch of those parts from Futurelec at some point in the past so that’s what ended up listed in the BOMs. They are completely commonplace and any sensible substitute is likely to be just fine.

The Thonk pots and knobs are a bit different though. The trouble is that the manufacturers of those things offer the parts in thousands of customisable varieties, with minimum quantities well into the thousands and price points that are only good in the hundreds of thousands. So there are usually only a few variants that are stocked by any reseller company that low volume purchasers can choose from. Thonk happen to stock a range that are really convenient for DIY use and very reliable, and they are geared up to handle low volume customers, so it makes a lot of sense to use them for those parts. I guess LZX could have designed their DIY cadet boards for the varieties readily available at one of the big electronics resellers, but honestly I think the Thonk choice was a good one.

Personally, I use knobs from various places. That’s one thing you can happily vary to your heart’s content. Just make sure your choice matches the shaft of the pot, and be aware that some knobs with large skirts won’t fit the modules.

#63 — reverselandfill · 2020-02-06

you can also search for 9mm rightangled pots in other places, if you like to hunt for cheap.

they might not have the same quality as the Alpha pots Thonk uses,

but still good enough for your use.

#64 — souka · 2020-02-06

I’ve been compilling a mouser BOM for the full Castle series (1 of each module) and mouser indicates that some parts are reaching their end of life and some have already done so, the website claiming they are obsolete.

One such example is the Metal Film Resistors - Through Hole 100Kohms 1% 100PPM. But in this case they indicate the corresponding substitute.

The same does not happen with the Multilayer Ceramic Capacitors MLCC - Leaded 0.1uF 50volts C0G +/-5% which is “Not recommended for new designs” and does not have a matching alternative.

The 1N4001 Rectifiers Vr/50V Io/1A T/R is also obsolete. No substitute is suggested by Mouser.

Could someone help me substitute these last two items? I understand they are somewhat simple components but I’m not that knowledgeable about this and would like to avoid wrong decisions.

There are other items nearing their end of life (as stated by mouser) but as they still had stock I did not write which. If I find the time I’ll revise the list and take note of all of these occurrences.

Thanks for your help!

#65 — Agawell · 2020-02-06

mouser’s substitution suggestions are not always 100% - I suggest that you actually search for yourself on mouser for similar items - just check that the specs are the same or very similar, if in doubt check back here

Both 0.1uF (100nF) 50v c0G 5% tolerance multi layer ceramic capacitors and 1N4001s should be easily available at mouser, they are really common

#66 — Agawell · 2020-02-06

here’s a selection of N4001s

https://nl.mouser.com/Search/Refine?Keyword=1N4001&Ns=Pricing|0&qty=100

and here are the caps

https://nl.mouser.com/Passive-Components/Capacitors/Ceramic-Capacitors/MLCCs-Multilayer-Ceramic-Capacitors/Multilayer-Ceramic-Capacitors-MLCC-Leaded/_/N-bkrdjZ1yzvvqx?P=1z0z7l5Z1z0wqusZ1yx4avvZ1yxbokaZ1z0x6frZ1z0vn3t&FS=True

but learning how to search in mouser and tayda and thonk etc etc is part of the skillset required for diy, especially for things that are EOLed, 90% of the time there is an exact replacement available

#67 — Jefro · 2020-02-06

Souka, would you mind sharing those BOMs? I need to go through that same process for myself soon.

#68 — souka · 2020-02-06

@Agawell you are correct, I should invest in learning more on the BOM creation part. Thanks for the advice and for the substitutes

I appreciate it.@Jefro I’ll share it. Just want to go over it once again to verify and clean it up a little. I’ll probably create a whole new post for that but I’ll let you know through here.

Edit — adding the Mouser BOM list.

@Jefro here are the files. If you can, double check everything.

GitHub

https://github.com/g-souka/LZX-Castle-MOUSER-BOMLZX Castle series Mouser BOM. Compilled for one of each module. - g-souka/LZX-Castle-MOUSER-BOM

Link: g-souka/LZX-Castle-MOUSER-BOM

#69 — Jefro · 2020-03-25

I just rolled with it and placed the mouser order for the full set. I did see a capacitor that was not available but it was all alone on the Bom and there were others of the same value. I just deleted it from the cart before placing my order. We’ll find out if I screwed up by doing that. One thing to note is that I’m not building the quad gate, so may not notice a few missing/wrong parts. I think I may have also removed a toggle switch that was unavailable, but I can get a good replacement locally.

My order just got here, so I’ll follow up soon.

#70 — Jefro · 2020-03-26

That cap that was unavailable at mouser turned out to be c14 on the Clock VCO. ( The 2nd module I built last night.) I used one of the other 0.1uf caps in place of it, assuming there would be one in the extra parts due to not building the Quad Gate. The Clock VCO I built works, but I don’t know how this cap will effect behavior.

#71 — Agawell · 2020-03-26

Which cap did you replace with which cap???

often they are dictated by what is either available or cheapest at the time of writing the BOM - caps or resistors of the same value/type can almost always be substtiuted without issue

#72 — Jefro · 2020-03-26

C14 on the clock VCO was swapped out with one of the other 0.1uf caps. The clock VCO cap was a C0G type, the one I replaced it with is a Z5U type.

For the time being, I just made the cap easy to spot so I can replace it with one more suitable, if need be.

#73 — Agawell · 2020-03-26

https://www.allaboutcircuits.com/technical-articles/x7r-x5r-c0g…-a-concise-guide-to-ceramic-capacitor-types/

I suspect you will be fine - there might be a little bit of noise introduced though

#74 — Jefro · 2020-03-26

There’s some noise when I’ve got it in horizontal mode for sure, less so with vertical. It should probably be replaced in the BOM as the part in the BOM is obsolete.

#75 — Agawell · 2020-03-26

hmmm, maybe but substitution’s an important skill to learn as is wokring out that, for example 0.1Uf is 100nF and 0.1nF is 100pF

it’s pretty easy

a good idea is to buy 100 of any common caps/resistors - I’ve got loads of 0.1Uf (100nF) C0G caps - they are ubiquitous - almost all synth DIY uses them

but individual part numbers come and go, as manufacturers update their lines from time to time

#76 — Jefro · 2020-03-26

Of course, but since the idea was to do that legwork here for others, it’s important that I call it out.

#77 — Agawell · 2020-03-26

the problem with that - and why people generally just leave the original BOM as is a lot - is that these things change with no warning - the newly substituted part is discontinued and replaced and then the BOM needs updating and repeats the cycle with another component and another and another

#78 — Jefro · 2020-03-26

And at that time the next person can do the swap themselves. Why so defensive about it? I’m just trying to help save some folks a little time. I could have just said yep, the Bom is good, or said nothing. But I made a promise to follow up if I saw issues, so that’s what I did. I’m not here for an argument.

#79 — Agawell · 2020-03-26

Sorry wasn’t trying to be defensive or start an argument

Actually I think it’s a great idea

#80 — Jefro · 2020-03-26

This Coronavirus thing has got me all wrapped up in my own head, I’m sure I’m not alone in that. So yeah, apologies if I got a bit out of line.

Anyway, now if someone follows the posts, maybe they’ll learn something about substituting caps, without doing it the hard way like me.

#81 — MrDys · 2020-04-18

As Thonk is not currently shipping to the US because of the pandemic, does anyone have another source for those 9mm B10k pots?

#82 — VisibleSignals · 2020-04-19

Pots are generally manufactured with specific options, and Thonk would have custom-ordered a large quantity of them to get them built specifically that way. They’re a great choice, but unfortunately not available anywhere else unless you order 20,000-odd from the manufacturer

However, I have successfully substituted these sorts of pots: https://www.taydaelectronics.com/potentiometer-variable-resistors/rotary-potentiometer/linear/10k-ohm-linear-taper-potentiometer-round-shaft-pcb-9mm.html

You have to carefully bend the legs 90 degrees out from the body, and then very carefully trim back one side of the thick part of the legs with a dremel in order to fit the PCB holes. It’s easy to accidentally cut the leg off completely, so be careful (maybe buy a couple of spares). It looks a bit hacky, but it works just fine.

I’m sure there are other places you could buy similar pots locally. Check the shaft to make sure it matches your pots, and make sure the body is the right size (i.e. distance from pins to the front panel) by reading the datasheet. Always read the datasheet

The ones I used were actually spline shaft, since that matched the knobs I had.

#83 — reverselandfill · 2020-04-19

Explodingshed sells them. (based in Germany)

you can also buy 9mm vert pots on alibaba, ebay etc.

#84 — VisibleSignals · 2020-04-19

I looked at the ExplodingShed web site (thanks for the pointer Martijn) but couldn’t see ones that were quite the same as the Thonk ones? They did have a suggestion for modifying other pots, similar to the way I mentioned.

On ebay I did find this one which is pretty similar (but rather expensive): https://www.ebay.com.sg/itm/15mm-Mono-Potentiometers-RK097N-10K-Ohm-Tone-6-Pins-Volume-Mixer-Pot-Contro/264695518200?hash=item3da11513f8:m:mK6FKFVcMjxKVgs-3QWe1PA

#85 — reverselandfill · 2020-04-20

I found these (not tested yet)

aliexpress.com

https://www.aliexpress.com/item/32766023946.html?spm=2114.12010615.8148356.3.75e55a85TSAADpSmarter Shopping, Better Living! Aliexpress.com

Link: US $58.9 5% OFF|Precision adjustable potentiometer R09 RK09 B10K B50K B100K...

aliexpress.com

https://nl.aliexpress.com/item/32954008988.html?spm=a2g0z.12010615.8148356.9.5ba74b94aNpN7USmarter Shopping, Better Living! Aliexpress.com

Link: US $65.6 18% OFF|100 stks RK097N RK097 RK09 verticale enkele bocht...

and cheap right angled

eBay

https://www.ebay.com/itm/5Pcs-ALPS-RK097N-B10K-Audio-Amplifier-Sealed-Dual-Potentiometer-15mm-Shaft-3pins/162259156171?hash=item25c7663ccb:g:VEwAAOSwHMJYEzaOSpecifications: Type:RK097N Resistance Value :10K Ohm Shaft Length :15mm Shaft Diameter:3mm  Package : 5  x RK097N   Potentiometer  Descriptions: Audio Amplifier Sealed...

Link: 5Pcs ALPS RK097N B10K Audio Amplifier Sealed Dual Potentiometer 15mm Shaft...

#86 — VisibleSignals · 2020-04-20

That last one looks very good - with a bulk purchase and combined shipping it would be a great price!

#87 — reverselandfill · 2020-04-20

wait, this one is the one I meant:

I’ve ordered this one a few times already, in packs of 100

eBay

https://www.ebay.com/itm/NEW-RK097N-Audio-Amplifier-Sealed-Potentiometer-3-Pins-B-5K-10K-20K-50K-100K-ohm/163409976591?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649Model: RK097N. (Choose what you need). We will be responsible for you.

Link: NEW RK097N Audio Amplifier Sealed Potentiometer 3 Pins B 5K 10K 20K 50K 100K...

#88 — Fox · 2020-08-26

Can anyone specify the bandwidth requirement that makes the LM6172 the only possible op amp? I understand that slow op amps within the video path will blur or muddy the picture, correct?

Mouser lists the LM6172 as having a GBP of 70MHz. The next opamp down in speed and cost is the NJM2068D with a GBP of 27MHz. This sounds like a big drop in bandwidth but I at the same time, 70MHz sounds like massive overkill when a colorburst signal is only 3.58- or 4.43MHz.

Correct me if I am looking at the wrong spec.

#89 — reverselandfill · 2020-08-26

the slew rate is also important

#90 — rempesm · 2020-08-26

I haven’t used that chip before but the slew rates on the datasheets for both chips look significantly different (6V/µs vs. 3000V/µs on the LM6172).

You could pretty easily compare them if you just breadboard a buffer circuit like this (remember 100nf bypass caps on V+/V-) and feed it signals with hard edges like a keyed shape or hi frequency square wave oscillators. It should be readily apparent on the output if the NJM2068D isn’t slewing quick enough.

The 1k resistors on the op amps are suggested in the LM6172’s datasheet for buffers. Not certain if that’s required for the NJM2068D or if you can get away with a wire link like in a TL07x buffer circuit. Let us know what you find out if you try this!

#91 — joem · 2020-08-27

Fox wrote:

Can anyone specify the bandwidth requirement that makes the LM6172 the only possible op amp?

It’s not the only possible opamp to use for video stuff. There are many fast opamps that will work, but it’s the one that LZX chose for their DIY designs. You may be able to use other opamps but they probably wouldn’t be a drop-in replacement into the existing Cadet boards.

I can’t speak for LZX, but if I had to guess why they chose it for the Cadet stuff, it’s probably because:

• same pinout as the common TL07x/08x series
• available in through-hole (DIP) packages
• available from major electronics distributors
• cheap(-ish) for a fast opamp meeting the other specs

Probably some other reasons too… maybe involving offsets or something else I can’t quite remember? The pinouts and the DIP packages especially mean that they’re easy for people to experiment on their own with and design new things, which I believe is something LZX wanted the Cadets designs to help with. And I know we don’t really think of them as cheap, but when you compare them to other video-rate opamps, they’re towards the lower (or lower-middle) end of the price spectrum (or at least they were when I looked a couple of years ago).

And the reason for the LM6172’s in the Castle line are probably all the same reasons as for the Cadet line, plus the fact that they were already used in the Cadet line (since Castle came later).

#92 — creatorlars · 2020-08-27

Here are the standards:

[WORK IN PROGRESS, FEEDBACK IN THREAD WELCOMED] > LZX Industries Patchable Video Standard V1.0> The Patchable Video Standard proposes an electrical and interface specification for wide bandwidth analog computing instruments intended for creative and expressive applications. It is optimized for, but not limited to: (1) generating and processing analog RGB video graphics in SD resolutions, (2) affordable devices which are accessible to working artists and not just big studios, and (3) maximum patcha…>

Slew rate is what you should care about when evaluating an op-amp. You want to look at the time it takes to go from 0V (black) to 1V (white). That time should be less than or close to 1x SD pixel (about 70 ns.)

LM6172 is getting more and more expensive since TI bought out National. But there aren’t any real alternatives with the same specs, price, available in DIP, and that can run on +/-12V power rails. We’re moving to SMT for our next rendition of DIY designs, and using the same opamps we use for production (ADA4851-x series, running on +/-5V power rails.)

#93 — Fox · 2020-08-27

Thanks for the replies, everyone.

The 70ns spec is essentially what I was after. I was able to find cheaper op amps with comparable slew rates but like Lars pointed out, the packages are different and most notably the max power supply ratings are lower.

Also much appreciated that no one has yet to speak down to me. What a refreshing community you have here.

@rempesm, I did toss a few of the 6v/us op amps into my cart along with all of the 6172’s that I need. At 54 cents each, I am curious just ‘how’ bad they can possibly look.

#94 — sean · 2020-08-28

I notice that Rochester Electronics has a stock of the obsolete, not lead-free version of the LM6172IN for less than half the cost of the NOPB version.

Though the minimum qty is 120. (Another group buy?)

#95 — rempesm · 2020-08-28

Yeah, you can get neat unintended effects with narrower bandwidth parts. Often it appears to be horizontal smearing or other filtering effects but you might get surprised. I usually stray away from IC sockets for video modules but you could try that on one of your builds to make comparisons easier. Breadboarding that buffer circuit and passing thru signals that sharply change from B<->W is probably the more direct way to roughly evaluate the difference. Breadboards will introduce some stray capacitance just like IC sockets.

#96 — rempesm · 2020-08-28

Do you need a chunk of them atm? The difference for the 500 and 1000+ tier seems kind of negligible. I’d be down to split a 120 pcs order with someone in the US but don’t have bandwidth to arrange a huge group buy sendout.

#97 — VisibleSignals · 2020-08-28

Sean, you’re a legend! Thank you so much for this!

Given I’m in Australia there’s not really any point in me sharing a group buy with you guys so I’ve just done my own order.

Now I just have to build up 120 x LM6172’s worth of video modules

#98 — reverselandfill · 2020-08-28

Now I just have to build up 120 x LM6172’s worth of video modules

OH no, what a disaster!

#99 — Fox · 2020-08-28

Good find! Put me down for 30-50. Maybe more. How many did you need? If we can get a group buy set up this week, that would be fantastic.

#100 — sean · 2020-08-28

Sorry, probably worded that wrong… I should have said, “Perhaps those that need some could arrange another group buy?”

Myself, I’m actually still working my way through my stock from the last group purchase.

But, yeah, I’d imagine getting a few people together to reach the 120 minimum shouldn’t be tough.

#101 — Rik_bS · 2020-08-29

Given I’m in Australia there’s not really any point in me sharing a group buy with you guys so I’ve just done my own order.

I’m in Sydney and plan to build a few Cadets & Castles over the next few months… might have to reach out to you to buy a few of those (if you don’t use them all yourself)

#102 — Robbertunist · 2020-09-06

Let us know how the visuals look when using those 6v/us opamps or post a link to some video, I’m curious.

#103 — Robbertunist · 2020-09-06

Thanks @sean

Anyone in Europe up for splitting an order? I’m in Berlin & would take about 50.

#104 — VisibleSignals · 2020-09-06

Just to close the loop on this, Rik & I are now in touch

#105 — VisibleSignals · 2020-09-09

Feeling amp’ed

#106 — jeffbbz · 2020-09-17

Can I replace the 1623934-1 0 ohm ceramic resister in Cadet I Sync Gen with this ZOR-25-T-52-0R 0 ohm metal film resister? Or also can I just use an extra leg off another component since its 0 ohm anyway? The 1623934-1 is only available in 4000s on Mouser and i don’t want to pay extra shipping to get it from Digi-key or something as I’m not ordering anything else from there.

#107 — rempesm · 2020-09-17

I just used a cutoff resistor lead for all the Cadet I builds I’ve done. Works fine.

#108 — jeffbbz · 2020-09-17

Thanks, that’s what I thought!

#109 — VisibleSignals · 2020-09-17

These days I prefer to buy a few of these and cut off a section whenever 0R resistors are required. It’s made a HUGE difference to the overall video quality in my module builds.

Addicted To Audio

https://addictedtoaudio.com.au/products/tchernov-cable-classic-mkii-speaker-cables?variant=31835618279520The modern generation of our best-selling factory terminated speaker cable incorporates totally redesigned conductor geometry and advanced complex insulation. Large 2.85 mm² BRC conductors minimize the overall active resistance and ensure efficient...

Price: AUD 1,090.00

Link: Tchernov Cable CLASSIC MKII Speaker Cables

.

.

.

I’m just kidding!!! Just use an old piece of wire

#110 — jeffbbz · 2020-09-21

FYI I tried to order from Rochester and I got this email:

Hello,

Thank you for your order, hoping you can help with some further information. Please help with all questions in order to process the order.

1. Please can you provide a copy of your business license and a link to your website?>>2. > Is your company an OEM, CM, Reseller, or freight forwarder?>>3. > Please can you confirm the device that the part(s) will be used in?>>>>

I’m still gonna reply to that but I feel like they are going to reject me for not being a real business?

#111 — Robbertunist · 2020-09-21

Fingers crossed somebody at Rochester reacts positively to your email @jeffbbz

#112 — VisibleSignals · 2020-09-21

They asked me the same questions so I made a web site and directed them to it and they were happy with that. If you run into problems I’m happy to submit the request and get them sent to your address.

#113 — Rik_bS · 2020-09-21

Curious about that, since I’m planning a Rochester order very soon… would they have any reason to not sell to hobbyists?

#114 — jeffbbz · 2020-09-22

We’ll find out because I decided to be semi-honest with them. I made it sound like I run a private video service+ device repair/building deal and didn’t have a site and etc.

I couldn’t find anywhere on the site that you had to be a business. And they let me register and order with a gmail address.

If they reject me I’ll either try again with my work email and site (and hope they don’t really pay attention that its not related at all) or go with @VisibleSignals’s generous offer.

#115 — jeffbbz · 2020-09-22

Speaking of pretending to be a business, I got quite a few parts for my upcoming builds directly from Texas Instrument’s site. You do have to pretend to be from a business, and have a website and a work email, but not much else and I just provided my unrelated ones from my work and although i haven’t gotten them yet, everything has shipped with no problems. The LM6172IN/NOPB’s are cheaper there than anywhere except Rochester and there’s no minimum order. Same goes for most of the other TI chips n’ such.

#116 — jeffbbz · 2020-09-25

Whelp. I was rejected. Rochester said that TI prohibits them from selling to anyone but distributors.

#117 — VisibleSignals · 2020-09-26

Interesting. And crappy

Given then that I’ve already gotten across the line with them I am happy to help out with a group buy if it makes financial sense. If they’re being pissy then they may not want to post to a different address to the one I’ve used previously, which would mean they end up going USA -> Australia -> wherever. Delivery to me was <1 week last time, and my cost (including postage) was AUD$412.11 for a quantity of 120.

Anyway, my offer is out there, but if you can find a northern hemisphere company to sort it out that would probably be a better option.

#118 — phosphenes · 2020-10-20

Does anyone know if I can substitute C18 and C19 220uF 6.3V Capacitors for 470uF OR 100uF on the Cadet II RGB Encoder? It forms part of the composite output from the AD724 along with a 75 ohm resistor. My gut instinct is that it its probably fine as the datasheet for AD724 doesn’t seem to go too specific on why it need the 220uF other than for passing low frequency.

#119 — VisibleSignals · 2020-10-20

I think it’ll be fine. They’re only there to eliminate any DC offset on the AD724 composite outputs. At worst, you can just try it out (there’s no way other values will cause any permanent problems) and if something isn’t right then try swapping them.

#120 — Robbertunist · 2020-11-10

Thanks again @sean for posting the link about the Rochester deal back in August

I got a batch of 120 so if anyone in Europe is in need od a few, please let me know. I’ve nearly gotten through the first 40, got 3 rows like in @VisibleSignals’s photo a couple of months back.

sean wrote:

I notice that Rochester Electronics has a stock of > the obsolete, not lead-free version of the LM6172IN > for less than half the cost of the NOPB version.

Though the minimum qty is 120. (Another group buy?)

#121 — sean · 2020-11-11

Nice!

With the stuff I pre-ordered from Visible Signals/@VisibleSignals, I will exhaust my own supply from the previous group buy and need to finally get more. …Though I might just go for a few direct from TI rather than trying to arrange a big/group buy in the U.S. this time around. (Not that I arranged the last one, but I did participate.)

#122 — Robbertunist · 2020-11-11

Hopefully the minimum order isn’t 100 or more at TI. I’m sure their prices were the best over here in Europe when I last checked a few months ago.

#123 — mrfang · 2020-11-15

I also gambled on LM6172s from eBay and ended up with fake ones.

So I’ve now ordered 116 from Rochester via DigiKey and should be receiving them in a week or two. If anyone in the US wants to buy some of them, hit me up.

#124 — sean · 2020-11-15

Hey, yeah, I might want to get in on that. Not sure exactly how many I need until Aladan posts the BOMs for his modules. But maybe ~15-20?

#125 — VisibleSignals · 2020-11-15

I’ve been working on them, really! I have a proof-reader who is helping now (thank you, anonymous proof-reader, you know who you are).

LM6172 counts:

• RGB Matrix (Starter Pack) = 15
• RGB Matrix (additional Input) = 1
• RGB Matrix (additional Direct In) = 3
• Video Mult = 1
• Dual Distrib = 4
• Wrangler = 3
• Quarterizer = TBC

#126 — Fox · 2020-11-15

I can finally offer something to this thread!

I picked up some XD1881’s which are drop in replacements for the LM1881’s, but at about 1/10th the cost. It looks like the thru-hole version from TI are now obsolete.

#127 — Robbertunist · 2020-11-16

I bought 10 for 10€ about 4 months back on eBay. Took about 2 months to arrive and with no immediate way to test them, I didn’t qualify for a refund once I got some Cadets built

Just plain stupid of me after reading so many similar stories on here.

Glad to read you bite down & put in an order for legit ones. I’m really glad I did it, its changed everything as they were the last thing I needed but stupidity hesitated on

Nice one @VisibleSignals for posting the LM6172 count on your modules, I’m sure a few of us here are gearing up for their arrival

@Fox, cheers for the tip, I’m really curious to see this chip in action. Have you been able to compare it in two of the same module or on a breadboard circuit?

#128 — Robbertunist · 2021-01-04

Hello everyone

For anyone in Europe who needs any LT1251CN or LT1256CN ICs, I bite the bullet & bought 25 of each to get the lower price point. They’re used in the a few of the higher number #Cadet range. The 1251 is also used in @VisibleSignals’s RGB Matrix Mixer.

I’ve also got well over 100 of the PJ302M right-angled jacks that I sourced directly from #Thonk & plenty of LT6172 Op-Amps so if you’re in Europe (or elsewhere for that matter), send me a message and I’ll check the postage costs or pop over to www.post.de for letters & small packages. Www.dhl.de/en has an English option for info & such.

To most of Europe a tracked letter under 50g costs €4.20. A tracked padded envelope up to 500g costs €6.30.

There’s a well stocked electronic component shop 5 or 6 mins by bike from me. Online orders can be picked up from their door so if you need anything, I’m happy to include them.

#129 — meudiademorte · 2021-01-05

Will write u when i checked how many i could use

#130 — dondon · 2021-01-06

Hello, was curious if anyone could recommend these ferrite beads from Tayda for LZX/etc DIY?

taydaelectronics.com

https://www.taydaelectronics.com/ferrite-components/ferrite-beads/axial-ferrite-bead-76-ohm.htmlKING CORE - Get It Fast - Same Day Shipping

Price: USD 0.08

Link: Axial Ferrite Bead 76Ω

76Ω as opposed to 68Ω recommended in the Castle BOM, wasn’t sure how much that mattered?

#131 — Fox · 2021-01-06

Really weird coincidence. Just yesterday I was going to post about those exact beads. I was making graphs comparing the cutoff frequency for both the 68R and 76R beads with the accompanying 10uF caps and got tired. It was really late.

Yeah, they’re fine to use.If you need more than 100 though, Mouser’s price break is a better deal for the 68R but the minimum shipping is $7.99. https://www.mouser.com/ProductDetail/623-2743001112LF/

#132 — dondon · 2021-01-07

hah, awesome, thanks!

#133 — sean · 2021-01-28

Okay, with some orders from Visible Signals and Syntonie and some other upcoming things, I think it is time for me to re-up my LM6172 supply.

@mrfang, still have any from your Rochester lot? I’d be looking for 20–25, depending on per piece cost.

Or does anyone else want to go together on another group buy?

#134 — mrfang · 2021-01-28

Update: sorry, @sean , I don’t have enough left to offer any.

#135 — Robbertunist · 2021-01-30

I’ll soon be ordering some more LM6172 ICs if anyone in Europe is interested in some. There’s some great news on Syntonie’s Modulargrid page

ModularGrid

https://www.modulargrid.net/e/syntonie-vu006Syntonie VU006 - Eurorack Module - Quadrature Oscillator

Link: Syntonie VU006

Checkout the VU005 & there’s a couple of others surprises too

@syntonie, are you going to create a thread on here regarding your new modules or is the info on #Modulargrid the result of a successful cyber hack of your servers & leak of your closely guarded corporate secrets

#136 — syntonie · 2021-01-30

Just listed them today

VU006 is audio rate so it doesn’t require LM6172, there is a few in CBV002/VU005 though. Will do a thread once everything is ready

#137 — sean · 2021-01-30

Re: VU007 Encoder

…however a RCA sync board could be designed and put in place of the existing power/sync board if there is any interest.

Going to jump the gun here and say, Yes, please!

#138 — Fox · 2021-02-03

The race is on.

#139 — sean · 2021-03-04

Anyone order LM6172s from these folks before?

Because, yeah, that’s a good price if they’re legit.

#140 — reverselandfill · 2021-03-04

they have a Anti-Counterfeit Policy | WIN SOURCE

but I’d say, buy a few to see if it is real, then buy bulk?

ps: in the specs, they have this: “Fake Threat In the Open Market = 46 pct”. I wonder what that means

#141 — Robbertunist · 2021-03-05

I have’t heard of them before. They’re Hong Kong based I think, basing that on the “same day” shipping option with a deadline of 2pm, HK time.

#142 — Robbertunist · 2021-03-05

reverselandfill wrote:

“Fake Threat In the Open Market = 46 pct”

That the likelihood of getting fakes when dealing with non-registered suppliers/distributors of TI ics is as high as 46%. We’ve both been burned by the fake 6172s on Ebay & Alibaba for instance as have many others on here over the last 3 or more years.

#143 — Rik_bS · 2021-03-05

wow! if I didn’t just buy 120 of them (Thanks aladan!) I’d order a small quantity just to test them first…

That said, shipping isn’t cheap so factor it in your overall saves.

#144 — VisibleSignals · 2021-03-05

You’re welcome Rik!

I did a bulk purchase of LM6172 and now offer them as add-ons with my Visible Signals DIY boards, for USD$3.20 each (cheaper than Mouser!) Most of the web site products are updated but there might be a couple of designs that are missing them - if you find one please let me know.

Cheers,

A.

#145 — Midcitysteve · 2021-03-10

Im interested in getting in on a group buy with you, if you still are looking for 6172’s I want maybe 30-40 and am in LA.

#146 — sean · 2021-03-10

Think I’m going to try out that Win-Source place. Will DM you the details.

#147 — sean · 2021-03-16

Win-Source LM6172 update: tried to order from them. They ended up contacting me a few days later saying the listed price was an error and that it would be a couple dollars or so more per chip. Thankfully, they were pretty quick to issue a refund.

#148 — Midcitysteve · 2021-03-16

Still down to order from rochester if you want to do that. Just let me know what the price difference will be.

#149 — jnoble · 2021-03-16

I need around 110 LM6172IN/NOPB–Rochester’s prices seem too good to be true compared to Mouser and Digi-Key … what’s the catch?

#150 — VisibleSignals · 2021-03-16

My understanding is that the catch is that you must be an OEM with a registered business and a relevant corporate web site to buy from Rochester. Their deal with the chip manufacturers is based on them selling to OEMs. Visible Signals (me) fit that description, but I had to prove it before they’d accept my order.

#151 — Fox · 2021-03-16

jnoble wrote:

I need around 110 LM6172IN/NOPB–Rochester’s prices seem too good to be true compared to Mouser and Digi-Key … what’s the catch?

The catch is that the parts are obsolete “leaded” versions. They are also sold through digi-key’s marketplace if you don’t have a website. The part I don’t understand is how they’ve maintained a steady stock of 525 pieces despite orders being fulfilled.

#152 — jnoble · 2021-03-16

The NOPB parts are the “current” lead-free versions; I see they have the lead-bearing versions for even cheaper, but I’ve given up lead for Lent.

I’d like to participate in a buy if possible, please let me know!

#153 — Fox · 2021-03-16

Rochester has NOPB too? I didn’t see that.

#154 — jnoble · 2021-03-16

Yep, right here and for a buck less/each compared to Mouser & Digi-Key in qty. 100:

Rochester Electronics

https://www.rocelec.com/part/TISLM6172IN-NOPBRochester Electronics is the world's most trusted solution for end of life semiconductors. Search our large inventory of semiconductors and buy now.

Link: Part LM6172IN/NOPB

#155 — wiatrob · 2021-03-17

Probably NOT the answer you all are looking for - but IMO the most effective thing to do would be to redesign the castles and cadets to use the new unipolar LZX reference design. The LM6172 was the parts choice for the time, but +/-12V is overkill for processing 0-1V signals. Also, make everything surface mount which would increase parts choice options and decrease prices as well as PCB real estate (not to mention the irritating and time consuming process of bending resistor leads). Of course this won’t help you to populate the boards you may already have.

#156 — jnoble · 2021-03-18

The parts count on these modules is not very high, so neither conservation of PCB space nor lead bending is high on my list of concerns.

Cost isn’t a major factor, either, IMO: most DIY modules’ biggest costs are in the PCB/faceplates and in the “mechanical” components: jacks, switches, and pots+knobs. An extra five bucks for opamps in the context of a $50-70 DIY module’s BOM doesn’t bug me much if it means I can stuff boards the good olde-fashioned way. If I can save a hundred clams when I need 100 opamps to build 30-40 modules, I’ll happily do it … but considering the “retail value” of the finished products is in excess of $4,000, I don’t consider Mouser’s prices as a serious obstacle.

Others may have different priorities, of course.

#157 — jnoble · 2021-03-19

Got 110 LM6172IN/NOPB in the Mouser cart for $3.88/ea. … I’m pulling the trigger since I’d like to get these builds in motion and parts are on the way from other sources.

LM1881 and CD4053 are a problem, however–does anyone have leads on these?

Here’s my build list:

(1) Cadet I

(1) Cadet II

(2) Cadet III

(2) Cadet IV

(2) Cadet V

(2) Cadet VI

(2) Cadet VII

(2) Cadet VII

(2) Cadet IX

(2) Full sets of Castle modules

(2) Syntonie V002 quad doublers

(2) Syntonie V005 dual waveshapers

About half these modules will be offered for sale, I’ll post about them in this forum first.

#158 — Fox · 2021-03-20

jnoble wrote:

LM1881 and CD4053 are a problem, however–does anyone have leads on these?

I posted an alternative part for the LM1881 above and TaydaElectronics has CD4053’s.

#159 — joem · 2021-03-20

jnoble wrote:

LM1881 and CD4053 are a problem, however–does anyone have leads on these?

I’m pretty sure you could get the LM1881 in a SOIC size (still in production) and use a cheap SOIC8-to-DIP8 adapter board. I actually have some on the way to me now so I can test them out like that. SOIC is pretty easy to solder even though it’s SMD – easier IMO than the closely spaced transistor footprints LZX used on some of the Cadet modules.

#160 — joem · 2021-03-20

Example of the adapter board I mean: 10PCS SOP8 turn DIP8 / SMD to DIP IC adapter Socket SOP8/TSSOP8/SOIC8/SSOP8 Board TO DIP Adapter Converter Plate 0.65mm 1.27mm|soic8 to dip8|dip8 to sop8soic8 sop8 dip8 - AliExpress

There are many many listings for them on aliexpress and ebay.

#161 — jnoble · 2021-03-20

Thanks for the tip–and it looks like LCSC has CD4053s also.

Do we know if this supplier is legit? I don’t care about the cost in this situation, the whole thing is less than 20 bucks. I just want good parts so the modules perform well.

#162 — Fox · 2021-03-20

joem wrote:

Example of the adapter board I mean: > 10PCS SOP8 turn DIP8 / SMD to DIP IC adapter Socket SOP8/TSSOP8/SOIC8/SSOP8 Board TO DIP Adapter Converter Plate 0.65mm 1.27mm|soic8 to dip8|dip8 to sop8soic8 sop8 dip8 - AliExpress>>>> There are many many listings for them on aliexpress and ebay.

Nice, thanks for the share. I just placed an order for these too.

I never order anything from Ali, so this is my first time.

jnoble wrote:

Thanks for the tip–and it looks like LCSC has CD4053s also.

Do we know if this supplier is legit? I don’t care about the cost in this situation, the whole thing is less than 20 bucks. I just want good parts so the modules perform well.

I have never had an issue with JLC or LCSC. I have a lot of circuit boards assembled by JLC, by whom I also get my PCBs made, and all of their parts come from their LCSC warehouse.

#163 — sean · 2021-03-31

FYI, buying (the obsolete, leaded version of) LM6172 from Rochester via Digi-Key marketplace required no special credentials or questioning (…thanks to mrfang for the tip!). There was a minimum qty of 117.

Midcitysteve (who, it turns out, lives just a few blocks away from me) and I now each have a healthy supply of them!

#164 — Fox · 2021-03-31

And they’ve finally updated the stock qty too.

#165 — rempesm · 2021-03-31

Yep, same experience. Took a little longer for Rochester to ship the items out to me than the rest of my Digikey order but $2.15/ea is a lot easier to swallow than some of the prices on Mouser these days.

#166 — jnoble · 2021-05-13

How did the XD1881s work out for you?

#167 — Fox · 2021-05-13

They’ve been fine. I have them in couple Cadets and a few of my prototypes without any issues.

#168 — jnoble · 2021-05-13

Great, I just ordered 10 of them. Thanks so much!

#169 — hewed · 2021-08-03

I’m on the verge of placing my first Mouser order to build some Castles and other units, but two parts on the Castle BOMs are out of stock and, in one case, showing as no longer available.

Does anyone have suggested substitutes for:

1. Mouser 512-MC79L05ACP - ON Semiconductor Linear Voltage Regulators 5V 100mA Negative
2. Mouser 512-512-1N4001GP - ON Semiconductor Rectifiers Vr/50V Io/1A T/R

Apologies if the answers are obvious, but I’m new to this stuff.

If anyone is feeling particularly helpful, I’m also looking for the Mouser equivalents of these parts from Tayda, for some @Fox modules:

taydaelectronics.com

https://www.taydaelectronics.com/mini-jumper-2-54mm-gold-plated-closed-cover.htmlGTK - Get It Fast - Same Day Shipping

Price: USD 0.02

Link: Mini Jumper 2.54mm Gold Plated Closed Cover

taydaelectronics.com

https://www.taydaelectronics.com/40-pin-2-54-mm-single-row-pin-header-strip.htmlGTK - Get It Fast - Same Day Shipping

Price: USD 0.15

Link: 40 Pin 2.54mm Single Row Pin Header Strip

taydaelectronics.com

https://www.taydaelectronics.com/2x40-pin-2-54-mm-double-row-pin-header-strip.htmlGTK - Get It Fast - Same Day Shipping

Price: USD 0.21

Link: 2x40 Pin 2.54mm Double Row Pin Header Strip

#170 — reverselandfill · 2021-08-03

863-1N4001G

511-L79L05ABZ-AP

jumper:

151-8011-E

header:

571-9-146282-0

#171 — Fox · 2021-08-03

Thanks, martijn.

You may use the single-row pin-header in place of the dual-row pin-header since you have to snip or break them to size anyhow.

#172 — sean · 2021-08-08

Based off the comment about capacitors in Syntonie’s VU006 module notes (that the C0G ones set the timing of the oscillator), I am guessing the same is the case for the C0G 0.1uF cap in the Castle Clock VCO — and thus shouldn’t be swapped out.

But I wonder if it is okay to swap the other specified 0.1uF caps (Vishay 1C10Z5U104M050B) for another one that I am planning to buy in bulk since I’ll be using it in a whole bunch of other modules (TDK FG18X7R1H104KNT06)?

#173 — Fox · 2021-08-08

sean wrote:

Based off the comment about capacitors in Syntonie’s VU006 module notes (that the C0G ones set the timing of the oscillator), I am guessing the same is the case for the C0G 0.1uF cap in the Castle Clock VCO — and thus shouldn’t be swapped out.

That is a good observation. For frequency stability, the C0G type (class-1) will be far more stable over a range of operating temperatures vs. Z5U or even X7R types. Have a look at this graph, though note it is exaggerated in scale to make a point.

You’ll see that the K-magnitude for U2J and C0G is incredibly linear over their full operating temperatures. Above and below the left and right sides are outside of their operating temperatures where they no longer work so you can ignore these extremities.

Here is a description of K:

The factor by which the dielectric material, or insulator, increases the capacitance of the capacitor compared to air is known as the > > Dielectric Constant> > , ( > > k> > ). “k” is the ratio of the permittivity of the dielectric medium being used to the permittivity of free space otherwise known as a vacuum.>>>> So as K changes, the capacitance values changes.

sean wrote:

But I wonder if it is okay to swap the > > other> > specified 0.1uF caps (Vishay 1C10Z5U104M050B) for another one that I am planning to buy in bulk since I’ll be using it in a whole bunch of other modules (TDK FG18X7R1H104KNT06)?

Yes. Unless specified, the stability for the rest of the caps is less important. I usually pick up X7R like the TDK’s you’ve found. They are plenty stable for general power-rail decoupling. Mouser keeps raising their prices week after week, so try not to spend any more than 7 cents on each cap.

These are slightly cheaper than the (TDK FG18X7R1H104KNT06), but both are good choices. K104K15X7RF5TL2 Vishay / BC Components | Mouser

#174 — Tim · 2023-01-01

Hey there cheers everyone first time post and in the midst of putting together a few cadet modules. My question is I ordered a number of cd4053’s and recieved cd74hc4053e‘s instead. Would this cut the mustard???

#175 — syntonie · 2023-01-01

Afaik, the CD4053 used in the Cadets is always powered with +5V/-12V, which is fine since it can withstand 20V between V+ and V-, whereas CD74HC4053 max voltage between V+ and V- is 10.5V, so it cannot be used as the chip will be damaged because of the exceeding power supply voltage.

#176 — creatorlars · 2023-01-03

@syntonie is correct. There are some speed differences too, so the circuit may not work exactly the same (may or may not create issues.)

#177 — Tim · 2023-01-12

Thanks y’all! Here’s another genius question ha! I’m trying to pinch pennies, but I’m not gonna jump the shark and ruin this whole process but I was wondering with some of the resistor values could I do a two resistor in series combo to get a few of the values i currently do not have? Or will this itself create more capacitance/circuit noise or other funky gremlins . Poor in the pocket, determined in the spirit, and vaguely grasping always

cheers!

#178 — rempesm · 2023-01-12

You can bodge resistors in series but the values do need to be within 1% of the stated resistor value on the BOM or the circuit will not work as designed. Test them with a multimeter before installing.

#180 — Tim · 2023-01-12

Cheers and tysm for such a swift reply!

#181 — J-DVR · 2023-06-11

Hi everyone! Has anyone (as of late) building the LZX castle series modules found (working) suitable replacements for the now obsolete parts:

MC78L05ABPX

&

MC79L05ACP

I hate to say that I thought I found some and might have fried/bricked a couple so far…please send help!!

#182 — Agawell · 2023-06-11

these are voltage regulators, aren’t they? I just checked on mouser for the 1st one and there are 15 alternatives… with almost all boxes checked - so they should be reasonably easy to substitute

#184 — Agawell · 2023-06-11

I can’t remember what I used - I built my castle modules a few years ago… all I can recommend is get the spec sheet for the originals and find something as close to identical as possible… and then ask if they are good substitutes…

#185 — Robbertunist · 2023-06-17

Have you got a breadboard & voltage metre device to test the voltage regulators you’ve previously sourced? It’s not hard to build a circuit to test the regulators & see if they’re outputing the expected 5V & -5V or the 78L05 & 79L05 regulators.

I remember one of my Castle builds required reflowing on a V regulator 3 times. The 3x pads were really close to eachother, parallel almost rectangles rather than a triangle made up of 3 circular pads. The case I tested would shut down intirely which freaked me out at first but didn’t damage anything in the end, as the circuit is designed, thanks to the reverse voltage protection diodes.

Feel free to post a photo or photos on here of the PCB/s. The obvious mistake is an IC that’s in the wrong way around, that’s almost 100% definitely going to fry an IC or ICs on a PCB unfortunately.

Hopefully you’ve found a solution since you posted @J-DVR

Update:

Here’s a nice example of building a 5V circuit rathering than testing a 5V regulator but if it’s steadily outputting 5V, it should be fine:

Instructables

https://www.instructables.com/Simple-5V-Breadboard-Power-Supply/Simple 5V Breadboard Power Supply: When I build a circuit on a breadboard, the first problem I always have is to create the 5V that will power the components. Of course there are a lot of pre-made power-supplies that you fit perfectly on the power ...

Link: Simple 5V Breadboard Power Supply

#186 — J-DVR · 2023-06-18

Thank you Robin for your response and the useful information!

Building a circuit to test would have been the plan…but this was one of the few times I had no extras left. I spoke to Phil briefly about it and he actually suggested the same exact thing.

Currently I decided to put a pin in it until the Fall probably. I live in the south USA and my workplace is not climate controlled…that and I’ve been too hyper focused on it so for my mental health as well I’ll be taking a break.

I will definitely come back to it and post if I need to. Hopefully score an oscilloscope in between and do some more studying / research before jumping all back in.

The hardest part for me (besides the modules not working after 15 mins or so) is soldering those pads…thank god for flux! …so it is interesting to hear you had to reflow 3 times. I’m still pretty confident without testing that I had some bad VRs but next time around I will be more mindful of possible reflowing and maybe just test the new VRs on a breadboard to be extra sure!

I’ll make sure to triple check those ICs also when I get back to it as well. Thank you again for the info!