Help w/ Noisy Cricket (Or, why I've always hated breadboards...)

Started by ayayay!, October 08, 2018, 08:57:09 PM

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ayayay!

After years of building pedals, then years of hiatus, I'm trying to get back into this.  I always hated my breadboard.  I never had one successful circuit built on one.  So I thought why the hell not give it another go?  I have built at least 2 of Dano's Noisy Crickets over the years on perfboard successfully, no problem.  But I want to get comfy with the breadboard, and after 3 nights I've had to come back to here.  ...I'm ready to chuck it but I want to breadboard for more freedom in experimentation.  So with a big swallowing of my pride, here we go...



Mods:  Omit power switch and grit switch.  Edit:   100uF across the rails is there. 

Results are the speaker sounds like it's at full volume with mild hum.  Touching the input cable does nothing.  Pot adjustments do nothing. 

Supply voltage is 8.94 VDC.

D:  8.94
S:  2.64
G:  0.00

1:  1.33
2:  0.01
3:  0.00
4:  0.00
5:  3.90
6:  8.94
7:  4.48
8:  1.34 

The people who work for a living are now outnumbered by those who vote for a living.

thomasha

Pictures would help, could be a short, or a missing ground somewhere in the audio line.

Rob Strand

If your breadboard has a metal plate under it connect it to circuit ground with an alligator clip.
If it doesn't sit it on a metal plate, or even a sheet of Aluminum foil, and ground it.

Grounding the metal part of the pots also helps.

Over the past few years there were a few threads about people's set-up for prototyping.  Many people have an L or U shaped piece of metal where the breadboard sits inside and you mount the pots and connectors to the vertical walls, which have pre-drilled holes.    These set-ups greatly decrease the problems with hum and noise when building audio circuits on bread boards.

Here's one, see Stalik's post #5,
https://www.diystompboxes.com/smfforum/index.php?topic=116423.0
Send:     . .- .-. - .... / - --- / --. --- .-. -
According to the water analogy of electricity, transistor leakage is caused by holes.

ayayay!

QuoteIf your breadboard has a metal plate under it connect it to circuit ground with an alligator clip.

Indeed it does!  I did not know that.  Thank you, will try it tonight.  My hope is high that this is all it is.  :)

It's like this one:

The people who work for a living are now outnumbered by those who vote for a living.

deadastronaut

https://www.youtube.com/user/100roberthenry
https://deadastronaut.wixsite.com/effects

chasm reverb/tremshifter/faze filter/abductor II delay/timestream reverb/dreamtime delay/skinwalker hi gain dist/black triangle OD/ nano drums/space patrol fuzz//

thomasha

but if changing the pots does nothing there must be a ground missing at the pots.

ayayay!

Quoteput a big cap across +/- .  100uf..

Oh yeah, it's there.  I didn't realize this schem didn't have it, I just put it on there from habit. 

Quotebut if changing the pots does nothing there must be a ground missing at the pots.

Entirely possible at this point.  There is a change in "buzz" when I adjust the gain pot.  I definitely have my volume pot "1" lug going to ground. 

The people who work for a living are now outnumbered by those who vote for a living.

slashandburn

You could always strip it right back down to the the "Smokey" amp, then add each other section until you find the problematic components or connections.

Or photos of what you have on the BB!

ayayay!

Sorry for the wild goose chase boys, it was just a bad volume pot all along.  I got good readings on one end or the other, but anywhere in between I had nothing.  Oh well, it's working.

Noticed it cuts out when I hit REALLY hard on my bridge PUP, then comes back after about 2 seconds.  Probably not the greatest design for a 4ohm speaker, and it's kind of a wimpy supply at less than 8.9V (Most are at least 9.6V)

Anyway, thanks for all the help. 

Edit:  Looks like a Little Gem may get me better results w/ my 4ohm speaker.  I'll try that this weekend. 
The people who work for a living are now outnumbered by those who vote for a living.

bamslam69

Good to see you discovered the problem. Breadboards are great!
Yeah Nah - Nah Yeah