[R-390] Should this work? YESSSS!

[Barry]

The B+ fuse was blown.  I thought I had checked it, but maybe not.  I didn't
have a 1/8A fuse, so I put the trusty amp meter across it set to the 120mA
scale and brought it up on the variac in the standby position.  It drew
about 5 to 10 mA in standby and about 70 to 80 mA in AGC position.  Yeah, I
know that when I switched from standby to AGC, there was a chance of it
suddenly drawing a lot of current through the meter, but I took my chances.
My Motorola is a 1-fuser, so I guess I wasn't too particularly worried.

I then took the IF output of the working receiver's RF deck and fed it to
the IF input of the "new" radio.  It worked great!  Even with my "golden
screwdriver" action on the IF deck, it still is aligned close enough to get
a good, clear audio path through it.  (Yes, I plan to align it too, but not
quite ready yet).

Next, I switched to the CAL position and ran the PTO down to the nearest
100kc position (I don't have the Oldham coupler installed yet), and I was
able to hear a weak calibration signal!  I was kind of surprised to hear
anything because I played "musical slugs and slug racks" when I rebuilt the
RF deck.  Granted, it hears nothing in the way of a signal all the way
through the RF chain, but that's expected.

A little more mechanical stuff to assemble and I'll be ready for a full
alignment.  The weekend is coming up and I don't have much of anything else
on the schedule so I know I'm going to enjoy it.  This is just too much FUN!

Barry - N4BUQ


> I think you may have the answer.  I grounded the point I was talking about
> earlier and that didn't help.  It grounds more than just the capacitor,
but
> it still didn't help.
>
> I put a tube extender on V509 and checked plate voltage at pin 6.  There
> should be185V there and I'm getting a small negative voltage (< 1v).
> Probably either a blown fuse or a bad wire in the harness.  Didn't have
time
> to explore any further on my lunch break, but I assume I'll find this
pretty
> quickly tonight.
>
> Thanks, guys!
>
> Barry - N4BUQ
>
> ----- Original Message -----
> From: "David Wise" <David_Wise at Phoenix.com>
> To: <JMILLER1706 at cfl.rr.com>
> Cc: "R-390 HF Receiver List" <r-390 at mailman.qth.net>
> Sent: Thursday, May 05, 2005 12:29 PM
> Subject: RE: [R-390] Should this work?
>
>
> (Three-fuse versions only) F103 burnt out will kill most of
> the RF-IF B+ while keeping the 0A2 alight.
>
> Dave Wise