What’s on *YOUR* workbench?

I revived an old project by special request. Onboard bass headphone amp with stereo aux in. It's been something like 2 years since anybody wanted one of these. I remember it was quite annoying to design the power-on scheme. It has to turn itself on and also turn on the bass's active EQ when you plug in just the headphones (not using the guitar cable). BUT, when you plug just the guitar cable (not using headphones), it needs to stay off so it doesn't waste battery. Seems easy enough, but there's only one available contact on the headphone jack to deal with the two power scenarios. Still gives me a headache to think about it.


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A skeptical buffer

I have enjoyed pedals going together easily and working first time for a while.

This one did not.
coincidence it’s the first thing I’ve made after switching to lead-free solder? Maybe?
It’s something in the power supply as not getting the correct negative current - 7660s in there rather than TC1044s because part missing…, would that make a difference ? I thought they were interchangeable?
 

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LukeFRC said:
I was trying to get arround issue with lead and kids being around
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Good point, but from the toxicological point of view, the danger excerted by organic lead compounds is way higher.
That's why we have unleaded fuel for decades.
I see the most danger in small batteries that could be swallowed accidentally. Same for those tiny but strong Neodym magnets.
Simply keep your electronic stuff (as well as detergents, pills, ...) out of reach.
 
#1 rule for for hospitals and leaded solder:
Wash your hands, don't touch your face, wash you hands, don't eat while you work, wash your hands, don't let kids eat things off the operating table, wash your hands.
There's probably more lead in the Lunchables and drinking fountains anyway...
 
Pauleo1214 said:
This pad should tell you all you need to know about riding her.View attachment 95538
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AHHH GEEEEZE MY EYES!
 
LukeFRC said:
A skeptical buffer

I have enjoyed pedals going together easily and working first time for a while.

This one did not.
coincidence it’s the first thing I’ve made after switching to lead-free solder? Maybe?
It’s something in the power supply as not getting the correct negative current - 7660s in there rather than TC1044s because part missing…, would that make a difference ? I thought they were interchangeable?
Click to expand...
How strange power out of the 7660 is steady +9 and -9 but the supply to the TL072 shows -17.7v and +1v

So something strange around there
 
jessenator said:
What the H*CK, Pennsylvania‽
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Topsoil lead concentration is highest in old population centers without coastal runoff. Before the late 1970s, leaded fuels/paint/etc., industrial pollution, and infrastructure materials all contributed to deposits. History of mining would also contribute (ref. CO) as well as drilling (ref. LA).

I’d guess overlaying that map with time-weighted population densities and watershed areas would align pretty closely.
 
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