Stuff you wanted to know but were afraid to ask

I had one (a question) but forgot it, so here's another one I came up with...

Most PullDownResistors are 1M or 2M2, but I've got a shipload of 6M2 — is this too high of a PDR value, how will it affect the rest of the circuit?

I read somewhere once that a PDR could be anywhere from 1M to 10M, but I can't find that reference again and whoever said it may have been full of bunk.

Sorry, I've been too lazy to do the math on input impedance etc...

Can I use my 6M2 stash for PDRs?
I dunno, but I’m breadboarding later…I’ll try it (though I’m sure someone will let you know anyway).
 
I had one (a question) but forgot it, so here's another one I came up with...

Most PullDownResistors are 1M or 2M2, but I've got a shipload of 6M2 — is this too high of a PDR value, how will it affect the rest of the circuit?

I read somewhere once that a PDR could be anywhere from 1M to 10M, but I can't find that reference again and whoever said it may have been full of bunk.

Sorry, I've been too lazy to do the math on input impedance etc...

Can I use my 6M2 stash for PDRs?
Here was my rudimentary finding; yes Virginia, you can use a 6m2Ω PDR…at least on a Burnin’ Rubber pedal (my personal breadboard of the Raincoat). I’ll just leave the 6m2 in there.
 
I had one (a question) but forgot it, so here's another one I came up with...

Most PullDownResistors are 1M or 2M2, but I've got a shipload of 6M2 — is this too high of a PDR value, how will it affect the rest of the circuit?

I read somewhere once that a PDR could be anywhere from 1M to 10M, but I can't find that reference again and whoever said it may have been full of bunk.

Sorry, I've been too lazy to do the math on input impedance etc...

Can I use my 6M2 stash for PDRs?
There should be no problem with that. Higher is probably better than lower (consider that an open circuit has infinite resistance).
 
Thanks Giovanni. I got two packs of 100 or more, can't even recall... it's a LOT. They were so cheap, sitting on the counter at the til, so I bought 'em. How often do we pedal builders need a 6M2, though. So ... good to know I can use them up in some way.
 
Did I say later? It’s 9:30…! We made Cuban chicken and rice (awesome btw Desi’s fav), which takes awhile but gee whiz!
I hope you chased that with a couple of Cuban sandwiches.
It's like putting a boost after a fuzz for extra oomph.

But back with pulldown resistors and eliminating pops. Let's if I understand this correctly:

>>>
While the effect is bypassed, the pulldown resistor at the input drains any stray voltage to ground so there's no pop on activation.
This is unnecessary at the output if there's a Volume pot because its lug 1 goes to ground so it accomplishes the same function. Otherwise another pulldown resistor last in the circuit can help.

The smaller the value of the pulldown resistor, the quicker voltage is drained to ground. Too low a value and you lose signal when the effect is on, so 1M is about the lowest we should go. Anything higher than that should also work but it will take longer to drain stray voltage.

Wiring the footswitch so it grounds the effect input on bypass is just an added level of safety against pops. Better safe than sorry.

Pops however can also have other causes like footswitch bounce and the LED, in which cases the above solutions will not work.
>>>

Is that right?
 
I drill enclosures by hand and sometimes it gets sloppy. When this happens, I’ll drill the hole a little bigger, or try to drill a bit toward where the pot or switch wants to go. Like so: 3E86C916-CDD1-4777-9E24-16C12B042391.jpeg
So my dumb question - is there anything bad about doing this??
 
I drill enclosures by hand and sometimes it gets sloppy. When this happens, I’ll drill the hole a little bigger, or try to drill a bit toward where the pot or switch wants to go. Like so: So my dumb question - is there anything bad about doing this??
That would somewhat depend upon your level of emotional investment. ;)
 
@Feral Feline weren’t we having a similar discussion in my thread ab my EUB preamp? I think what we came down to, based upon examination of the AMZ mosfet booster was that R1 set the input impedance. The combo of R1 and C1 set the frequency response. So for the AMZ booster, it had a 10M R1 and a 1nf C1 which has an impedance of 10M and a frequency response down to 15Hz. So an R1/pull down of 6.2M = an impedance of 6.2. You might want to see what your input cap value is and run some calculations to see how that effects the frequency response. Anyone feel free to point out any erroneous info I have passed off as actual knowledge of things.
 
Random question I just thought of while working on a project yesterday: How come most component values seem to be kind of "odd" numbers?
(Not literally odd/even but just...not particularly "round")

Take resistors for example. You'll often see values of 470R, 4.7K, 14.7K, 47K, 470K, etc....but then it seems like more "round" numbers like 500R, 5K, 15K, 50K, 500K are comparatively much less common. Or even more so for caps: I feel like I'm using 4.7nF or 47nF caps all the time, but almost never 5nF or 50nF, for instance...

So I guess basically I'm just wondering in theory how we got to that "scale". It feels like one of those things where it's like Celsius vs Fahrenheit or Metric vs Imperial where one tends to produce more "round" numbers than the other, but I'm not sure what the alternative would be here... Don't know if that question makes a lot of sense or not, but just kinda had that thought recently...
 
Random question I just thought of while working on a project yesterday: How come most component values seem to be kind of "odd" numbers?
(Not literally odd/even but just...not particularly "round")

Take resistors for example. You'll often see values of 470R, 4.7K, 14.7K, 47K, 470K, etc....but then it seems like more "round" numbers like 500R, 5K, 15K, 50K, 500K are comparatively much less common. Or even more so for caps: I feel like I'm using 4.7nF or 47nF caps all the time, but almost never 5nF or 50nF, for instance...

So I guess basically I'm just wondering in theory how we got to that "scale". It feels like one of those things where it's like Celsius vs Fahrenheit or Metric vs Imperial where one tends to produce more "round" numbers than the other, but I'm not sure what the alternative would be here... Don't know if that question makes a lot of sense or not, but just kinda had that thought recently...
I believe it’s so things don’t get mixed backwards. You’ll have 4.7 but not 7.4; 3.9 but not 9.3 etc
 
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Random question I just thought of while working on a project yesterday: How come most component values seem to be kind of "odd" numbers?
(Not literally odd/even but just...not particularly "round")

Take resistors for example. You'll often see values of 470R, 4.7K, 14.7K, 47K, 470K, etc....but then it seems like more "round" numbers like 500R, 5K, 15K, 50K, 500K are comparatively much less common. Or even more so for caps: I feel like I'm using 4.7nF or 47nF caps all the time, but almost never 5nF or 50nF, for instance...

So I guess basically I'm just wondering in theory how we got to that "scale". It feels like one of those things where it's like Celsius vs Fahrenheit or Metric vs Imperial where one tends to produce more "round" numbers than the other, but I'm not sure what the alternative would be here... Don't know if that question makes a lot of sense or not, but just kinda had that thought recently...
 
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