ProCo rat issue

Started by Elijah, April 05, 2021, 04:23:21 AM

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Elijah

Hello everybody. I'm building a proco rat from electrosmash. Did draw the pcb myself but have no sound coming out. Audioprobed and found out that no sound going out of pin 6. There is a sound before the pin3 of the IC but it's quite bad. Even from the input wire the sound is saturated in a bad way almost like a bad contact but it's sturdy actually. I've measured the voltages on IC and they're:
1-9,19
2-2,04
3-2,29
4-0
5-0,02
6-9,51
7-10,10
8-9,89
Power supply shows 10,10V.
Any help is wildly appreciated.

antonis

Pics... pics... pics...  :icon_wink:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

Elijah

#2






So I've done some mods. The output transistor-buffer is changed to opamp-buffer. Also added a booster after/before depending on how to wire. Also there's a toggle to choose between Ge or Si clipping.

EBK

#3
I don't know how much help I can be, but I have some "concerns" about your build, and some if this maybe could relate to your problem.
1.  You have some long uninsulated wires running around and through several components on the topside of the board.  These could cause any number of unintentional short circuits.
2. What is going on in this section of your board?

That obtuse-angled trace seems to be broken at the bottom, and it seems to be taking an oddly long path to get to where it is going.
3.  You have soldered wires to the eyes of the potentiometers instead of the lugs.  Those eyes are not intended to be used this way.
4.  You are using some quite thick hookup wire.  Thicker wire tends to be more stiff, which can more easily lead to breaks at the board as you move things around repeatedly.
5.  Your solder joints all appear to be dull and frosted looking.  What kind of solder are you using? 
6. Before Duck comes along and asks (perhaps impolitely impatiently :icon_wink:), could you give us a schematic?
  • SUPPORTER
Technical difficulties.  Please stand by.

Elijah

#4
Thank you so much for all the help.
1. Can a wire short to the enclosure of resistor or cap?
2. This happens while I was hitting it before etching ;D the transferred image was smeared.
3. What would the the purpose for those eyes then?
4. I took notes on that.
5. Don't know much about the solder brand. But it does work
6. Will do


EBK

Quote from: Elijah on April 05, 2021, 06:59:01 AM
Thank you so much for all the help.
Well, I think I was nitpicking more than helping, but I at least had good intentions.   :icon_wink:
Quote
1. Can a wire short to the enclosure of resistor or cap?
Generally, no, and I don't specifically think it is causing your problem.  But, there is a nonzero risk of creating unseen problems (there are a couple of spots where it looks "close" to an uninsulated part lead).
Quote
....
3. What would the the purpose for those eyes then?
They are essentially rivets for providing a mechanical connection between the lugs and the pot's PCB.
  • SUPPORTER
Technical difficulties.  Please stand by.