[AMRadio] SS Rectifier Replacements

[James M. Walker]

FWIW,
I run four DX-100s in various systems, and the quickest way I know to
burn out the HV transformer is to solid state the power supply. Caveaut
Emptor, but I did the solid sate thing, it ran for a couple of weeks, then 
poof!
HV transformer went. Only thing I know that does it quicker is Paul W0RWs
DX-100 in Beacon mode on 480KC, that went pretty quick and it wasn't
solid stated, I don't believe.

Keep in mind the rigs are older than most of us, was probably abused by 
someone
at one time or another, and really prefers the circuit designed for it. I 
ended up with
a lot of them (DX-100) because it was easier to buy the whole rig than wait 
for
parts that fit and work properly. As usual, YMMV!
Jim
WB2FCN

----- Original Message ----- 
From: "Stevan A. White" <w5saw at pathwayz.com>
To: <w5saw at pathwayz.com>; "Heathkit Mail List" <heathkit at mailman.qth.net>; 
"AM Radio Mail List" <amradio at mailman.qth.net>; "New Old Stock Group" 
<newoldstock at yahoogroups.com>
Sent: Friday, April 27, 2007 11:18 AM
Subject: [AMRadio] SS Rectifier Replacements


> Greetings All,
>
> I have a DX-100 I'm working on (albeit slowly) getting on the air.  I'm 
> going to make a few modifications to the audio circuit to satisfy my 
> vanity, change caps and replace the tube rectifiers with solid state.  I 
> know that this will give me a few more volts and stabilize the PS circuit 
> somewhat.
>
> I have run across the 1N1239 replacement which seems to be the standard 
> replacement for a long list of tube rectifiers including the 5R4, 5U4, and 
> 5V4 to name a few.  That's handy for me because I can replace my HV and LV 
> rectifiers with the socketed solution and not cut up the circuit too 
> badly.  At the most, I'll have to resolder a wire on the socket. 
> Everything will still be nice and clean.
>
> My concerns are simple.  What can I expect in the way of problems if I use 
> these marvelous devices?  Since I'll be changing the filter caps anyway, 
> should I beef them up somewhat?  What is the recommended value to use with 
> the 1N1239.  Anything else to expect or look for, namely inrush current 
> problems?