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Hi guys, I am making a couple of circuits and I'm trying to find out what people use to coat the back of the PCB for circuit protection?
These circuits are designed to be onboard and I'm worried that having the pads exposed could bring problems.
What would be a good and cheap method to coat the back of a pcb?
I have tried Araldite and Locktite Plastik. Both of them don't seem to be the way to go.

If we're talking about just the standard cap + pot to ground, the voltage division changes, but the overall resistance of the pot remains the same. So no it's fixed in that regard, that's why you get the 'high cap' across pins 3 & 2 in amps etc.

So, the cutoff frequency remains the same, no matter where the volume sits!?
I was reading about the Fuzzface technology on a website and it said there that the cutoff frequency changed depending where the Volume was sitting. It is confusing as I thought it wouldn't make any difference, in terms of setting a cutoff frequency.

A simple question.
Impedance aside, on a typical situation where there's an output cap and a Volume pot in series with it, it forms a high pass filter. Well, does this filter change depending on where the pot sits, or is the series resistance in the audio path added to the resistance tied to ground?

I had to read it about five times thinking "I've never heard of a multi oil pickup".  Right about the time I figured I'd missed out on a new wave of technology (like the Fishman Fluence) it occurred to me it was a typo.

I'll now crawl back under the rock I emerged from.

This technology is not new, is quite old in fact, it just never picked up.

A TL062 is the low-power version of the TL082. The TL072 is the low noise version of the TL082. So, you'd save power consumption, but possibly introduce noise.

You might also consider the TL022. It is slightly different, but still a dual op amp with the same pinout.

https://www.ti.com/lit/ds/symlink/tl022.pdf
https://www.ti.com/lit/ds/symlink/tl062.pdf
https://www.ti.com/lit/ds/symlink/tl072.pdf

I thought of the tl062, but if noise would be a problerm, which I don't know if it would, I would prefer to pay a bit more and get something else, maybe a newer opamp with better specs for the intended use.
Unfortunetly I do not know of what's been released nor or where to look. I have used the Tl022 before as a replacement for the tl062, I belive for LFO.

Hi guys. I'm building a summing amplifier to mix a multi coil pickup. Since my bass already has another circuit preamp in it I was thinking of using something that performs as good as as a tl072 but with lower power consumption and same or less noise.
I would appreciate any suggestions.
Thank you

Hi, I have this board that is made already and uses one side of a TL062 as an LFO in a PT2399 chorus. Meanwhile the other opamp is left hanging. Does any one know how to properly terminate that opamp? I saw that wiring it as a voltage follower is the way to go by adding two resistors from the input to the Rail and 0V. Is that right? If that is right what value should it be for both resistors?
Sorry for the silly question.

Hi guys.
Trying to figure out a way of using a diode in series with the rail with the potential of losing the least voltage possible when powering from a 9v source.
The diode being used at the moment is a 1n4001 but that drops the voltage a bit and it would be good to try and keep the voltage as close to the source as possible when using it in series.
Hope someone will have some helpful information on this.

Thanks

They were binned long ago. But you couldn't really tell the difference visually from what I remember. We've been getting them from Das Musikding since and had no issues.

I get mine, usually, from Musikding or Banzai as well and have never had any problems.

Wow, that is some crazy oscillation. Is there a noticeable difference on how those chips look from one another, or do they both look exactly the same? I mean same printing, same brand...etc.

Hi guys.
Got this wah wah pedal dated from 1979 that it's not working.
It uses two bc184C transistors, for reference, even though I have noticed that on similar circuits (fuzz wah pedal) found on the web, the second transistor is a bc167B.
The pedal has bypass working, when the effect is engaged there is some signal going through but at a very low volume and the pot is doing something but barely and very focused on the lower frequencies.
I have tested the switch and it's fine; wired an external pot to see if the pot was the problem, it is not. Checked if there was voltage going to the circuit from both battery and power supply. Replaced the caps and transistors to no effect.
Also inverted the second gain transistor to match the pinout of a bc167 but the result was exactly the same.

I am wondering if this could be an inductor problem? I don't have a lot of experience with Wah wahs, so, I don't know how to evaluate the inductor.

Hopefully someone could help with this one.

All the Fuzz Wars I've seen have the Ge diode pair. This might be a way to cheap around not using them.

It's possible. It's a NAMM edition, apparently onw out of 50. It sounds really good in my opinion, but it's really hard to compare cause it's the only original I've played.

Somnif, thank you for showing me that article. You might have solved the mistery I will socket these two and experiment and AB it with the original.

True, regarding the diodes, but the other circuits that have been traced, that I have found online, report to have two 1N34A.

It's intriguing. Would two Germanium diodes be a close equivelant to one Red LED clipping wise?