I’m just wondering if the panel finish has some kind of corresponding “touch up Paint pot or pen”, like with cars?
Or just get in there with the metallic Sharpie and make that scratch a legend.
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Black nail polish?
Jfkdbdjcbdmlsbdnskdbdn
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Just leave the LED out until you can afford a correct one, fairly sure it will have no effect on the output.
i just stuck one under the other, its powerful enough to shine through without looking weird, i guess the frosted look of the LED ends helps diffuse it some. Thanks all for the suggestions.
I put a kids plaster on the scratch and gave the panel a kiss, how long do they take to heal? 
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Well this is frustrating and annoying!
I’ve got the 1161 mult put together, but something is wrong and I can’t figure out what!
Using the bipolar LEDs - when I plug in the power, they automatically turn red.
Other than that, it doesn’t work at all. No signal passes through at all. Any obvious mistakes I’m just overlooking?
I’ve check all resistors multiple times, replaced all ICs more than once. Any help is appreciated!
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Hi,
Maybe try to remove the TL072 and test again. That is the one driving the LEDs.
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It’s the only component common to both multiples, so if there is only a single fault it kind of has to be either the power or that chip or its socket. Check it and the others to verify they have the correct supply voltages getting to them, that the power rails/ground are not shorted (downstream of the 10R resistors), and that none of the other IC pins are shorted to power rails or ground.
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what happens if you remove the 72?
cant see the other side so can’t see shorts.
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Hey everyone - sorry for the delayed response!
When I take the TL072 out, the LEDs go off, but still no signal passes through. Here are photos of the other side. I’ve built about 10 Kosmo modules with little trouble, and of course one of the easiest ones is giving me the most trouble!
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Did you do the tests I advised?
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Hey!
I’m still super new, so I’m unsure how to test the voltages of the chips and what voltages I need to look for
There are two 10R resistors, one end of each connects to the power header and the other to the rest of the module. (You can test continuity to the power header to check which end is which.) With power off, you need to check continuity from the latter ends:
Should have continuity:
- 10R on +12 V rail to pin 4 on each TL074 and pin 8 on the TL072
- 10R on -12 V rail to pin 11 on each TL074 and pin 4 on the TL072
Should not have continuity:
- 10R on +12 V rail to ground
- 10R on -12 V rail to ground
- 10R on +12 V rail to 10R on -12 V rail
- 10R on +12 V rail, 10R on -12 V rail, or ground to each other IC pin (TL074 1–3, 5–10, 12–14; TL072 1–3, 5–7)
You can then verify by applying power and measuring voltages from IC pins to ground:
- Pin 4 on each TL074 and pin 8 on the TL072 should have +12 V
- Pin 11 on each TL074 and pin 4 on the TL072 should have -12 V
- With no signals plugged in, all other IC pins should have 0 V
- With a signal plugged in on each input (say +5 V), all other pins should have that voltage (+5 V)
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Thank you so much for taking the time to walk me through this, it really does mean a lot that people are meaning to help!
All voltages look good on both TL074s, but I was definitely getting some funny readings on the TL072. I removed the socket completely and noticed this scratch across a trace. Is it possible that this is shorting to ground? If so, is there a way to fix it?
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That should already be the ground plane I think, so it shouldnt be a big issue on its own.
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Hey Kosmo fans 
I know, I feel like I’ve missed the party and I’m starting way too slow, but I am having fun, and that’s what counts!
I hadn’t done any soldering in a while, so I built 1 each of Sam’s 5012 jack and 5013 1/4" potentiometer breadboarder modules, a Frequency Central power supply and a Nelson Audio 24 plug power bus. Having gotten that far, I finally started on the #1161 mult. I got it together and I used a Behringer Crave for the source and destination of my first test. I ended up taking the Crave’s ‘LFO TRI’ output to the mult ‘in’ and took one ‘out’ back into the ‘TEMPO’ input on the Crave. Not great music 
but it proved the mult was working. I think I probably need to do the #1222 VCO now. Wish me luck!
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I uses this cable type to connect 3.5 jack to 1/4 , it would save you using the adapter.
Good luck for the VCO built !
kenable 3.5mm MONO Jack Plug to 6.35mm MONO Jack Plug Audio Cable 2m [2 metres] https://amzn.eu/d/eYESbOp