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My RA17 has been in storage unpowered since 2006. Prior to that it was in tip top condition having been serviced by Rob Filby in December 1999. I know it was unwise and neglectful of me not to power it for so long. What should I do now to bring it up? I have a mains variac. Can I use that? What is the procedure?

Thanks, Andrew.

You have the best means of powering-up after a long period already. . .
Capacitor electrolyte in high capacity smoothing power supplies in
particular are notorious for being ineffective: possibly shorted: and even
blowing up the can with messy results.
Slowly increase voltage with the variac to reform electrolytic capacitors
with an ammeter in series with the mains output to the set: and if possible
another across the ht link to monitor current to ensure not excessive from
that normally expected.
Check voltages around the set afterwards.

Douglas Denny. G3ZQE.

On Sun, 9 Feb 2025, 22:37 Andrew Holme via groups.io, <andrew=
[email protected]> wrote:

My RA17 has been in storage unpowered since 2006. Prior to that it was in
tip top condition having been serviced by Rob Filby in December 1999. I
know it was unwise and neglectful of me not to power it for so long. What
should I do now to bring it up? I have a mains variac. Can I use that?
What is the procedure?

Thanks, Andrew.

Hi,
A little more detail.
Using the variac to bring up the HT slowly is good. Probably best to put the system switch in Standby as this puts a fixed load on the HT line and isolates the rest of the set the rest in case of drama.
There wont be any HT voltage on the capacitors until there is enough voltage on the rectifier heaters for conduction to start. So good idea to monitor the HT voltage across the fixed resistor so that you can see what is actually happening to the electrolytics.
Assuming all goes well and you get to full HT without any snap, crackle or pop, then it is time to repeat the process but this time with the System switch in Operate, so that you give all the other electrolytics in the set the chance to reform. if all goes well you can then start looking for all the other faults which will have developed over 20 years of idleness.
Have fun
Peter G8BBZ