New cot50 weirdness

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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ansil
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my favorite amplifier: my hughes and kettner blue 30r
Completed builds: 3 jcm 800 builds
4 vintage plexi builds
2 bogner ecstasy preamps [both for personal use]
10 marshall guvnor mods and builds
100 jungle kat boosts
too many penguin love's to count.
5 blues pearl purplexed
dozen tube screamer fulldrive whatever you call them variants

hell i can't type this long it will piss off people what can i say i have been doing mods on toyz appliances gear sex toyz computers and such for 27 years. i started when i was 6 taking stuff apart.
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Post by ansil »

So I had never heard of the church of Tone.
An old friend of mine bought one of my DS1 pedals and he asked me if I were still fixing stuff and I said yes.
He had he said it with an older model.
Didn't work from the day he got it had the Box and everything.
I cracked it open and I looked at the board and noticed there's 2 capacitors missing.
Lo and behold it's the input and the output capacitors.

Now the strange thing is this is the exact same schematic layout as everything that I have seen on the Web however the board value parts didn't match what was on the board. Or if they did they were different than all the schematics have seen.

1st of all let me apologize I haven't been here in a while if I missed the post I did search to see if this was on here and I did not see anything relating to.
2nd please try to look over my spelling and punctuation I am having to use voice to text I had cancer and 4 rounds of chemotherapy and it has calls me to have really bad neuropathy and I can't type on the phone or the computer.
I have a picture of the board I did not grow up a schematic see above.
The noticeable difference is the input capacitor with point 022 microphone.
Feedback resistor was 3.3 Meg
Is diodes are 1 and 34A.
The board called for A2N5088. A2N5089 was utilized.
That last one was not that big of a deal.
Also it was a 4.7 K resistor instead of a 3.3 collector.
I will post a picture.

I don't have a way to post the picture right now I just added an attachment.

I hope you all are all doing well.
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Manfred
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Post by Manfred »

First of all, sad to hear that you have cancer and are suffering the effects of chemo.
I wish you very much that you will get well again.
You have nothing to apologize for.
There are many versions of the original COT50 derived circuits, some were also extended by further circuit parts around it.
For example, the Lovepedal Chula has the same value for the capacitors at the input and output.

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Post by stomper »

I’m very sorry you are dealing with cancer and chemo. A good friend of mine is suffering with this also. He is unable to play his telecasters. He has about 12 of them. If you don’t mind, I will pray for your complete recovery.

This looks like someone “borrowed” a few components for another project and forgot to replace them. Fortunately, the pcb gives the missing part values. Putting in some replacements, and a quick once over on any broken solder joints should get it going again.

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bmxguitarsbmx
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Post by bmxguitarsbmx »

Good to see you back around here ansil.

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ansil
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Posts: 491
Joined: 03 Mar 2009, 21:49
my favorite amplifier: my hughes and kettner blue 30r
Completed builds: 3 jcm 800 builds
4 vintage plexi builds
2 bogner ecstasy preamps [both for personal use]
10 marshall guvnor mods and builds
100 jungle kat boosts
too many penguin love's to count.
5 blues pearl purplexed
dozen tube screamer fulldrive whatever you call them variants

hell i can't type this long it will piss off people what can i say i have been doing mods on toyz appliances gear sex toyz computers and such for 27 years. i started when i was 6 taking stuff apart.
Location: cleveland tn
Has thanked: 15 times
Been thanked: 13 times
Contact:

Post by ansil »

Thank you everyone yeah I never really laughed I just had to shift gears in my life it wasn't doing a lot of repairs or modifications.
And the stuff that I was doing wasn't really that interesting.
I have been building off and on the optical light booster.
And slowly it's been coming together looks like we have a new pedal line that I'm going to be part of with a friend.
I am designing the circuit and building the pedals and he is marketing and designing the look.
Unfortunately I can't say much right now.
Also yes I pulled the transistor out because the one they were using I was testing it to make sure it was still good it had a insane amount of current draw.
But it worked so we put it back in.
And the input in the output capacitors they just never put a man from the factory.

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