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May 30, 2023, 03:11:37 AM

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are rows of knobs (pots, potentiometers) like old Christmas tree lights (series)

Started by saturated, March 18, 2023, 04:24:46 PM

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Quote from: saturated on April 11, 2023, 08:45:27 PMglad to see you recommend using mouser or digikey....was tempted to go elsewhere.
if there is anything else I should get from there let me know I hate to spend $7.99 on a $3 order.
Any kind of shop supplies or tools you might need.  Solder, solder wick, heatshrink, test clips, pliers, cutters, etc.

Quote from: saturated on April 11, 2023, 09:30:54 PMresistance across C58 about 3.5kohm
No shorts or excess load on the +9V rail indicated.  Might have been that just the regulator went bad.


hello friends
Im thinking I made incorrect measurements or something..maybe there is an insufficient ground...(I dont know anything...just guessing with my limited knowledge)
anyhow since 7808 seems to test ok out of circuit I will put it (or replacement) back in and test more points.
I really have a feeling this is going to be something really stupid like a deficient contact....ground...switch...jack...idk.

thanks again you guys rock !!


If you are not very used to reading schematics or looking at PCB overlays, especially larger ones where the tracks are very close it might be a good idea to print the layout on paper and use highlighter pens to mark out ground, +9v, -9v or any part of the circuit you are tracing.

Use your computer to crop and print the area you are working on, or maybe go to a library or somewhere and print it out at A3 size.

I always use the earth from a nearby component, in the Peavey that would be the part I coloured green, the minus side of C58 should be ok.
On a PCB with so many links you might have a bad solder joint where you might loose the earth signal going to the part you are testing.
Very often the centre tap of the transformer is connected to the earth, or 0V.
That would be the red/yellow wire from the transformer in this case.

Once you mark out the power rails and the traces you are following it becomes easier to follow the the layout.
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There are no stupid questions.
There are only stupid mistakes.


well guys apparently hell has frozen over because I ordered some 7808ct voltage regulators
they had different letters and stuff and i didnt understand the differences so i got a few different ones.  digi key had a $4.99 ship for light orders so I jumped on it

in honor of hell freezing over....I leave you with this


well guys i have been super busy but i finally soldered in a new 7808CT

and measurements are promising

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well you guys fixed it

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YOU GUYS FIXED IT!!!!!!!!!!!!!!

SSGUITAR #1 !!!!!!!!!!!


 :)  :)  :)  :)  :)  :)


sorry to ask two more questions to the SSGUITAR GODS

(I humbly bow down to them)

1.  does speaker polarity matter?  I have blue and yellow on one and red and black on the other

2.. do I need to put a little heat sink on that part we just installed.

you guys #1!!!!


Good work, Glad to hear it's working again. ;)
Re speaker, Either way is fine, it only matters when you have more than ONE speaker THEN you have to make sure the polarity is IN Phase.
When more than one speaker the sound still works and no damage is done while out of phase but you tend to notice a loss of Bass.

When I met my wife years ago she had a stereo unit and she said her friend had the exact same unit but it had much better bass so I checked and sure enough the speakers were wired out of phase,, swapped the wires on ONLY One and bingo she then heard the Bass that was missing.

Yes adding a slip on heat sink can't hurt.