[R-390] The adventure begins (and a capacitor question).

[Jim Temple]

 On Chuck Ripples web site is a file that lists "problem" caps in the
R-390A.

 The very first thing I would do would be to check the tightness of all the
grounding points, above and below, all the modules.  This includes tube
socket screws and under deck transformer mounting points that serve as
grounding points.  Also, look carefully at all the solder joints and redo
the ones that are not smooth and clean.

 Jim
>
> ----- Original Message -----
> From: "John Saeger" <john@whimsey.com>
> To: <R-390@mailman.qth.net>
> Sent: Tuesday, May 21, 2002 12:30 PM
> Subject: [R-390] The adventure begins (and a capacitor question).
>
>
 > So my R-390a has arrived.  I know there are things that one should do
> before
 > turning it on.  I checked the fuses and replaced a bad one.  But then I
 cast
 > all caution to the wind and turned it on.  I'm not sure if it's
completely
 > functional.  The line audio stuff doesn't seem to do anything, but it
 plays!
 > Sounds great through a Klipsch Heresy.  A vintage speaker that's too ugly
 > for my living room.  So the overpriced shipping may have worked out.
 >
 > It's a little bit moody though.  Maybe a lazy capacitor or something like
 > that.  So I'm thinking the first thing to do is start replacing
 capacitors.
 > I'm guessing if it's electrolytic, tantalum, or paper, it wants to be
 > replaced.  But my question is, what's the best capacitor to replace the
 > paper capacitors with?  Polyester, polypropylene, ceramic or something
> else?
 > I get the idea that the *orange drop* is popular, but has anybody ever
 > thought of using ceramics to replace some of the paper ones?  Maybe they
> are
 > even more reliable than the orange drops.  You can get 0.01 uf in a 1000V
 > version, and you can even get 0.1uf in a 200V version.  So it may be
 > possible to replace all of the papers with ceramics.  But I don't know if
 > it's a good idea.  What do you guys think?
 >
 > John
 >
 > _______________________________________________
 > R-390 mailing list
 > R-390@mailman.qth.net
 > http://mailman.qth.net/mailman/listinfo/r-390
 >