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View Full Version : Bringing old HiFi back into service tips and tricks .



goraman
11-06-2023, 01:25
After removing the tubes and cleaning the pins and sockets, checking to be sure the correct fuses are installed .
I clean everything free of dirt and oxidization ,rust ,corrosion, inspect inside and out for bulged capacitors ,leaking or any component that appears damaged by heat . If the inspection goes well. I bring it up slowly over several hours on a veric watching the amp meter for signs of failure.

I try to keep things original by reforming capacitors slowly then once the amp reaches full voltage , I check the bias , rest it . Then run it in hooked to small monitors.
I'd like this thread to be tips for bring back equipment that has not been powered up for decades.

goraman
11-06-2023, 01:45
Just a few more pictures.
There is something so satisfying, when you get several old amps, recivers up and running agein.
Some of those older capacitors come back well enough they don't need replacing right away.
Newer equipment, electrolytics don't last nearly as long.

Barry
11-06-2023, 06:36
One of your amplifiers looks like a David Hafler design. Am I right? :)

walpurgis
11-06-2023, 07:49
One of your amplifiers looks like a David Hafler design. Am I right? :)

The power amp looks like an ST70 and the monos have Dynakit badges, so likely Hafler designs.

goraman
02-07-2023, 15:30
I just picked up 2 preamps for those Dynakit 70's to clean up and test.
The Fisher 500C is done and so is the H.H. scott.
I am learning a lot about setting bias on different amplifiers.

Wakefield Turntables
02-07-2023, 17:22
I have no tips, only a couple of comments. Firstly, what a good idea for a thread. Secondly, being in the USA you will have access to many of the classic pieces of valve kit that most of us Brits can only dream of seeing, finding, or hearing. Looking forward to seeing how this thread pans out.