18 watt type amp, no sound

[buckshot78]

thanks for your help

[crgfrench]

What is the amp you bought, the one you're trying to clone?

[crgfrench]

It looks like you have the anode of the big black electrolytic filter cap going to ground. That would be backwards.

[buckshot78]

Thanks for your help

[Bieworm]

Did you measure the voltages at all B+ nodes? Checked plate resistors?

[buckshot78]

Thanks for your help

[buckshot78]

Thanks for your help

[Bieworm]

If there is someting wrong with a resistor it should be measureable.

[crgfrench]

A bad electrical connection can cause high resistance. Maybe recheck your solder joints, they look pretty rough in general. Also there seem to be burn marks from your soldering iron on some of the caps, maybe you fried one?

[buckshot78]

Thanks for your help

[JMPGuitars]

Please don't take this personally, but that build looks like a nightmare. As people mentioned, the soldering is not great. The flux you're referring to should be cleaned off after soldering. Excess flux is not a good thing.

Please read the linked articles in my signature for solder technique, and grounding.

If you're going to try and copy another amp, the first thing to do is draw a schematic of it, and then have somebody review it before actually trying to build it. If it doesn't make sense on paper, it certainly won't in reality.

Thanks,
Josh

[geoff 1965]

when you tested the cap did you test it for leakage not capacitance?
be careful until you find where voltage is going,you can build a simple bulb current limiter if you don’t already have one.

https://youtu.be/wRFRwOnLsZI

[buckshot78]

Thanks for everyone's help. I'll keep pointing around and figure it out.

[geoff 1965]

it’s a bit unnerving not being able to see the grounding lug for the cap but have you tried unsoldering the ground leg of the cap then checking the voltage across the 100K’s ? making sure the cap has discharged voltage first! notice you don’t have a bleed resistor across the 1st can capacitor.
good luck and be safe

[crgfrench]

What is that 5W 10k cement resistor for? I don't see it on the schematic. Cap drain?