[Milsurplus] [ARC5] Opinions on ARR-7. (Excerpt From Secret WWII Publication)

[Todd, KA1KAQ]

On Tue, Aug 28, 2012 at 10:31 AM, Mike Hanz <aaf-radio-1 at aafradio.org> wrote:

>> Notice that the mythological PP-33/AR 60 c.p.s. power unit is mentioned
>> in the description.  I suspect it never saw deployment...the publication's
>> description for the companion AN/ARR-5 mentions only the PP-32/AR.
>
> Great catch, Mike!  I did briefly look at that yesterday, but missed the
> PP-33/AR designation...I think partly influenced by its errors - look at
> http://aafradio.org/countermeasures/ARR-7.jpg and see if you can detect
> a presence of the "omitted" 21-42MHz band on the bandswitch. :-) Oh, and
> the claim for FM reception must have assumed slope detection - there
> certainly isn't a switch position for it.  What they may have meant was
> that for frequencies above 28MHz, the ARR-5 is used, and that does
> include an FM capability.

That makes sense, particularly in tandem set ups. The S-27 was a late
30s/early 40s design as I recall. Pretty good working rig for the
time, the Brits put them to good use tracking down Knickebein.

Here's my question on the ARR-7, which will no doubt reveal my almost
complete ignorance on WWII countermeasures: If the youtube video
posted earlier is a "slowed down" tuning rate, just how was this
receiver used? Assuming a video/panadaptor output, what information
could be gathered manually at such a high tuning rate, and how was it
gathered and used? I'm just looking at it and thinking....yep, you can
tell there are some signals on the band, but that's about it.

Certainly there would've been far fewer signals to seek out, perhaps
that's the secret? Fast scanning allowed finding a scarce signal that
was on the air briefly? The advent of recorders, computers and so on
make it a moot point, of course.

~ Todd,  KA1KAQ/4