[Premium-Rx] Racal 6217

[K0DAN]

Hi Geoff...

Thanks for your execellent history of the RA-6217. I have to pipe up that
it IS one of my favorite receivers! It is definitely a bit  different, and
rather rare,
but it is a very good performer for me.

I own one of the FCC versions of the RA-6217, which also has the RA6337A VLF
Preselector/Converter. I have to say it's one of the most sensitive and
selective receivers I own. I really like using it as a band cruiser. If run
with gain wide open and without preselectors, it is subject to overload, but
with judicious use of RF gain, attenuator, and preselectors, it can hold its
own.

This is a receiver you have to "drive"; it's definitely not a novice
receiver. Once you get used to it, it is pretty user friendly, but it does
require some learning curve.

The sensitivity, stability, and selectivity are excellent. I'm sure if
compared to, say an R-390, it can be beat in these categories, but so are
many, many other vintage receivers. Speaking of R390, which is a mechanical
marvel as well as an electronic one, the RA-6217's tuning  mechanisms are
also pretty amazing.

As to audio quality, I run mine to stereo amplifier with booksheld speakers
and a subwoofer, and the audio (again...when the receiver is proeprly
adjusted) sounds extremely good. This goes for SSB, AM, and even CW. The AGC
has very fast attack and decay, which is typical of a lot of the
commercial/military receivers, and sounds rough when compared to amateur
receivers. (The solution is to ride the RF gain control.)

As to all those jacks on the back, it is easy to run to a scope and use as a
spectrum monitor
( "panadaptor").

Anyway, I wanted to put in a few good words for this vintage premium
receiver. I agree that it is a "must have" for collectors. I have a bunch of
pictures...if anyone would like see more, please contact me off the list.

Regards,

Dan
K0DAN




----- Original Message ----- 
From: "Geoff Fors" <wb6nvh at mbay.net>
To: <Premium-Rx at mailman.qth.net>
Sent: Sunday, December 09, 2007 1:19 PM
Subject: [Premium-Rx] Racal 6217


> The Racal 6217 series was their first solid state receiver, and the Wadley
> Loop RF design is basically that of the original vacuum tube RA-17.  The
> 6-
> in the prefix denotes it is a product of Racal Maryland as opposed to the
> U.K., where the receiver was known as the RA1217.
>
> There are all sorts of variations of this set and quite a few accessories.
> A couple of models were designed for use in a master oscillator
> multiple-operator station, and do not have both tuning knobs. There is
> even
> one without any tuning knobs!  Those were used where a particular operator
> was only permitted to scan up and down a small swath of spectrum (e.g.
> CIA.)
> Those are almost useless and a couple of friends were stung paying good
> money for them without knowing what they were doing.
>
> The front end of the 6217 is relatively poor.  In the later models there
> is
> a blue AMP connector on the rear which is to be cabled to the 6397
> accessory
> preselector module, in which there are L-C filters 1 MHz wide for each of
> the bands the set covers.  Performance is about what you would expect from
> a
> first-generation solid state receiver from 1966.
>
> Some of the 6217's were used by the FCC in the late 1960's for off-the-air
> frequency measurement; there was an accessory comparator scope and
> frequency
> standard made for that purpose.  You will notice all sorts of little
> connectors on the rear panel which provide tapped outputs from the various
> oscillators and stages inside.
>
> Most 6217's have just the 600 ohm low-level audio output module which is
> something like 10mw maximum.  There was an output module which gave
> speaker
> audio, but none of the 6217's I had came with one.  This looks like an
> ideal
> task for a couple of cheap computer amplified speakers.
>
> Alignment of the 6217 is not trivial, requires a sweep generator and
> scope,
> and is best avoided whenever possible.  I was never able to get the AGC to
> my liking.
>
> It's a matter of personal opinion but I found it unpleasant to operate
> because of the control ergonomics.  I guess for a collector of receivers,
> it's a must-have, but I have yet to hear that it's anybody's favorite.
>
> Geoff
> WB6NVH
> Monterey CA
>
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