From: "Al Parker" 
Subject: Re: Fw: [drakelist] TR-4C


Hi Robert,
    If I had it, I'd ck the pwr supply first.  Had the fuse blown when you
found it?  Disconnected from the rig, short the 2 ctrl pins on the connector
to pwr it up, then measure voltages.  Are the HV, ~720 no load, and LV, ~
265 no load, on the proper pins of the connector, and nowhere else?  etc.
Is the ground lead continuous from the inside thru the connector?
    Check the fuse lamp in the antenna ckt, thinking of possible lightning
thru the ant connector, tho' you said it was disconnected so probably not
there.  That R-47 still bugs me.  Ck C161 between the ant. relay & R-47.  Ck
D12 at R-47.   Check the resistance of the 235v line to gnd should be close
to what pin 5 of V17 is said to be in the chart.  I can't believe that
something in the 235v line shorted & caused all those resistors to go.
    My mind usually shuts down abt now, guess that's abt it for tonite ;-)
CU tmw,
Al
----- Original Message -----
From: "Robert Lawson" 
To: "Al Parker" 
Sent: Wednesday, July 30, 2003 6:28 PM
Subject: Re: Fw: [drakelist] TR-4C


> Al,
>
> I've had the rig for a while.  I went though and re-tubed and re-aligned.
It
> was working like a dream yesterday.  I just turned it on this morning went
in to
> get another cup of coffee, and holy smokes when I came back out into the
shack.
>
> I am going to track down electrolytics in the radio on that 235 volt line
> downstream of the resistors.  I will be a small chance of having one
> electrolytic taking out all of them.  The other thought (yours) is a
voltage
> spike i.e. maybe from lightning hitting the power lines yesterday.  We did
have
> a storm but I was away and the shack was disconnected from the AC mains
along
> with the antennas.  All the resistors are charred all the way through big
time
> but the 235 white/orange wiring in the rig is fine. I know if I replace
all the
> resistors and turn it on,  they will all melt down again.
>
> I will keep you posted.  I do hope I can get it going again as it is a
very very
> late serial numbered TR-4c in excellent condition.  If you think of
anything
> more please email me.
>
> Regards,
>
> Robert W4RL
>
> Al Parker wrote:
>
> > hI Robert,
> > Here's one from Michael Smith, who's a good Drake guy.
> > Have you changed anything?  Like Michael says, & I did, it looks like a
> > wrong voltage.  Have you been using the rig before this happened, or did
you
> > just get it?  You said it was your first Drake.
> >     Getting a little more response now it looks like.
> > 73,
> > al
> > ----- Original Message -----
> > From: 
> > To: "Al Parker" 
> > Sent: Wednesday, July 30, 2003 6:05 PM
> > Subject: Re: [drakelist] TR-4C
> >
> > > Hi Al,
> > >
> > > I can't post to the drake list from here and might not get a chance
> > > tonight. I have been wishing I had a tr4c schematic here at work.
> > >
> > > Anyway, I would tell him to see just what are his power supply
voltages.
> > > Maybe HV and B+ touching, reversed, something like that. I think he
said
> > he
> > > just got it and that could mean anything. We have all seen some pretty
> > > shabby things done by folks who have no business with their mitts in a
> > > radio.   :-)
> > >
> > > In case this helps.
> > >
> > > Michael
> > >
> > >
>
>



----------------------------------------------------------------------
Submissions:        drakelist{at}www.zerobeat.net
Subscribe:          majordomo{at}www.zerobeat.net - subscribe drakelist in body
Unsubscribe:        majordomo{at}www.zerobeat.net - unsubscribe drakelist in body
Hopelessly Lost:    majordomo{at}www.zerobeat.net - help in body of message
Brought to you courtesy of TLCHost.net  http://www.tlchost.net/
----------------------------------------------------------------------

---