[R-390] R: R390A Blowing fuses...newby question

[R. David Eagle]

Hi Francesco,  I have located the problem and it looks like the sigmapert 26z5w soft starts died on me.  I found the original tubes and put them back in and it works fine now except the power switch issue.  I suspect the contacts got welded...seems to be a common problem.  I have never taken the front off so that will be another challenge!
Can you send me the info on the filter and cl you put in yours?
Thanks,
DaveKb8nnu

Sent from Yahoo Mail on Android 
 
  On Mon, Mar 30, 2020 at 2:32 AM, fdigio1 at gmail.com<fdigio1 at gmail.com> wrote:   Hi Dave,
Have you checked the power switch?

73, 
Francesco - IN3XZP

-----Messaggio originale-----
Da: r-390-bounces at mailman.qth.net <r-390-bounces at mailman.qth.net> Per conto di R. David Eagle via R-390
Inviato: domenica 29 marzo 2020 22:09
A: r-390 at mailman.qth.net
Oggetto: [R-390] R390A Blowing fuses...newby question

I have been working through the alignment procedures outlined in my manual and am now on day 3 of it.  Everything was going great with the alignment yesterday and receiver was on WWV and sounded great.  I came in this morning and flipped the switch on to warm it up, and poof the fuse blew.  I was extremely blown away because it was working fine when I shut it down for the evening.
So I went through and pulled all of the plugs off the modules except main power supply plug.  I put a new fuse in and poof...it blew again.  I pulled the rectifiers which are actually the soft start upgrades from sigmapert, put a new fuse in and everything seemed ok as the transformer powered.  I then became suspicious that that the soft starts went bad and I plugged one of them in  and it powers up fine with it in either socket.  Here is the weird part - I did the same to the other one and it works fine as well, BUT if  I have both plugged in it blows the fuse.
So I then pulled out the original 26Z5W's and plugged them in and all is good until one of them warms up and the fuse blows.  I then verified the wiring on the drawing and traced one wire that comes from the rectifiers to CR102 and unsoldered that and still get the same results.
Another odd thing that has transpired is that when the radio is switched to the off position, the frequency lights are on....???
Has murphy decided to come play for the weekend or has my radio been plagued by the Corona?
Thanks again,
Dave
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