[Racal] Re: [SWL] RE: RACAL RA 117 - FAULTS

Wed, 14 Apr 2004 11:16:00 +0100

Hi.
     With ref to faults on RA117, the following website holds some articles
which I wrote regarding fault finding and servicing on RA17 rxs.

http://homepage.ntlworld.com/steven.whiting/ra17l.htm

A lot of the faults are similar. In my experience of repairing numerous
17/117 rxs, the main faults with the 117's can
be listed as follows:

1. Non-linear 2nd VFO
2. 2nd VFO drifts (modified with a zener diode)
3. Faults around the 3rd and 4th mixer stages.

Fault finding on the 117 is fairly straightforward, just follow the signal
injection and tracing method as outlined in the
manual.

Trouble is caused by the silver mica caps in the 37.5 and 40Mc/s BPF stages.
Most of the faults I have encountered have been in the 3rd and 4th mixer
unit, typically a .02 uf cap which nearly
always is way out of tolerance.

Anymore help required just let me know.

Rgds Rob.

----- Original Message -----
From: "Ed Tanton" <[email protected]>
To: "Nigel Boyd G0UGD" <[email protected]>; <[email protected]>
Sent: Sunday, April 11, 2004 5:48 PM
Subject: [Racal] Re: [SWL] RE: RACAL RA 117 - FAULTS

> Hi Jim... talk to Nigel: <[email protected]>... he knows a LOT about
> anything RACAL. Also, I have forwarded this to my RACAL reflector. Perhaps
> you'll see some help there.
>
> At 10:02 AM 4/11/2004, you wrote:
>
> >Hi, from a sunny Johannesburg
> >
> >I have recently purchased a RACAL RA 117, however, it has a problem or
two.
> >
> >The RF output is very low and I cannot seem to find the source of the
> >problem. I can receive a (strong) close-by shortwave station (BBC on 6190
> >from the Meredale tx) but the signal is very weak, ditto any signal that
I
> >inject from a signal generator.
> >
> >It seems as though most of the caps and resistors are the orignial
(Hunts -
> >not my favourite make of cap!). Nothing looks "cooked". Oddly, there is a
> >fair voltage - to the touch - between the antenna socket and ground?
> >Curious - a cap?
> >
> >The set was promised in working condition! We've all heard that before,
and
> >it looks to be in good shape. Perhaps I am overlooking the obvious that
some
> >one out there has already discovered in their ownership/operation of one
of
> >these (otherwise) superb sets.
> >
> >
> >Regards
> >
> >Jim
> >Johannesburg
> >South Africa
> >
> >I am sure this is not for general Hallicrafters Inc interest, so, please
get
> >in touch with me directly if you can suggest my next move - not a box of
> >matches and a gallon of gas! It really is worth fixing!
> >
> >
> >
> >
> >
> >
> >
> >
> >----- Original Message -----
> >From: "Charles B" <[email protected]>
> >To: <[email protected]>
> >Sent: Sunday, April 11, 2004 11:58 AM
> >Subject: Re: [SWL] SWL] Re: Antenna Question Was I "discovered" a neat
> >trick.
> >
> >
> > > Hi All,
> > >
> > > I use an MFJ 1700b Coax connecting device for my antennas.  You
> > > can connect six antennas to six receivers. And to get a little
> > > more functional, I couple that to an MFJ 1704 with 4 in and one out
> > >
> > >
> > > Chuck
> > > ka4prf
> > > Clewiston Florida
> > >
> > >
> > > _______________________________________________
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> 73 Ed Tanton N4XY <[email protected]>
>
> Ed Tanton N4XY
> 189 Pioneer Trail
> Marietta, GA 30068-3466
>
> website: http://www.n4xy.com
>
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>
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