#1
Hey everyone.

I have an old semi-functional Silvertone 1465 from the 60's that I'm hoping to repair.
It powers on, but has a noticeable hum that I'd like to get rid of.

I'm pretty sure the original caps are still in there, so I think it's time for a recap job.

I've never done something like this, but I'd really like to learn rather than taking it to a store.
I attached a picture of the guts of the amp.

Should I only replace the six large red and single large blue electrolytic caps, or try to replace every single capacitor in the whole circuit?

Also, should I trust my multimeter readings for the capacitance of the caps?

Thanks for any help!
Attachments:
IMG_1514.jpg
#2
I also can't seem to find the output impedance for this amp.
Can anyone help me out?
#3
If it's a solid state amp then I'd just go for 8 or 16 ohms impedance. Solid states don't mind more of a load, just less of a load. As for the caps, what kind of multimeter do you have that measures capacitance?? It should say the value of the cap on the cap. And I'd say the caps your should be most concerned about replacing are the ones in the power supply section, so the biggest ones. If there's a cap can, replace that.
#4
Ok I'll look for a cab with at least 150 watts and 8 ohms. Most 2x12s should do the trick.
The multimeter I have is a Mastech MS8261. It was cheap and has worked great.

I'm not sure which caps are in the power supply section. I assume the large red and blue ones are the filter caps. I'm planning on replacing them, but I have no idea what to replace them with or what the best replacement method is.

Also, what did you mean by a cap can?
#5
Wow I didn't know they made multimeters that measure capacitance hahaha. A cap can looks something like this:


They have multiple capacitors in 'em, used on old amps. But as for replacing caps, you replace them with a capacitor of the same value and the same (or higher) voltage rating. I'd replace each cap one at a time, that way you don't get confused. The values and voltage ratings should be printed on the cap, it may be a code.
#6
So it doesn't matter what type of capacitor I replace the old ones with, as long as it has the same (or close) capacitance rating and the same or higher voltage rating?
#8
And if I replace all the large electrolytic caps and I still have the hum, should I replace ALL of the other caps in the amp?

That would be a heck of a job...
#10
Yeah it's too bad the guy I bought it from didnt have the cab. For 20 bucks I can't really complain, though...
#11
So I finally plugged it in and powered up.
All four inputs on both channels work. There is some hum, but it's not too bad. The main problem is that the reverb and tremolo knobs do nothing on all four inputs.

What's the best way to debug the circuit and get them working?

I might melt and reheat all of the solder joints in the amp to make sure I have no cold joints.