[ARC5] ARR-1

[Leslie Smith]

  Thanks for your correction Brian.  I'm posting to the rest of the
  group to correct my mistake.
  Incidently if I had taken the time to think a little my explanation
  (that the "0" was missing is obviously wrong.
 A good design wouldn't cover the frequency range my mistake suggested. 
 But it could (and did) cover the range suggested when the "2" is put in
 place.

 Interesting - I used Mr. Google to try to check my facts and Mike Hanz
 page didn't appear in the first two pages of results.
Anyway, for your "heads up" in the difference between "2" and "0" I say
"thank you".
Very few people take the time to correct mistakes, as you did for me.

  73 de Les Smith
  vk2bcu at operamail.com


On Tue, Sep 16, 2014, at 21:15, Brian Clarke wrote:
> Hello Les,
> 
> The ZB's, ARR-1's and ARR-2's frequency range was around 240 MHz. The 
> initial '2' was left off the tuning dial, not the final '0'.
> I think the similarity between the BCB and the beacon Rxs is irrelevant.
> The 
> beacon Rx could not be used with the ZB equipment and would never have
> been 
> found connected to it in a salvage wreck.
> 
> The Japanese were well aware of VHF during WWII. Professor Yagi and his 
> English translator assistant Dr Uda collaborated to develop the parasitic 
> antenna before WWII. Akio Morita, who founded Sony, was a RADAR engineer 
> during WWII, which was where he learned how to miniaturise electronix 
> equipment.
> 
> Cheers, Brian, VK2GCE.
> 
> On Tuesday, September 16, 2014 7:03 PM, you said:
> 
> >  Jim,
> >
> >  <snip>>
> >  It seems to me that the ZB apparatus was used to guide pilots to
> >  "base" - sometimes an aircraft carrier.
> >  Therefore - it was essential (if I'm correct, as I believe I am) that
> >  this gear (or even a knowledge of it's existence) never fell into Jap
> >  hands.
> >  The disguise here seems to be several layers deep.  For a start the
> >  frequencies on the "ZB' converter were displayed missing the zero, so
> >  when the dial read "42" it was tuned to 420 MHz etc.
> >  Next, who would imagine modulating a 420MHz signal with a 1MHz
> >  carrier?  So (if the Japs had a receiver that would receive VHF (I
> >  doubt this) and the "tuned" the "ZB" signal - they would hear nothing.
> >  You need to convert the VHF signal to the BC band, and then demodulate
> >  that signal.
> >  Finally, the deception depended on the similarity between the BC band
> >  receiver (CBY-46145) and the lower frequency nav band receiver
> >  (CBY-46129)
> >  If the BC band receiver appeared superficially similar to the normal
> >  nav. band receiver, it would not attract much attention to a casual
> >  observer.
> >
> >  It may be I'm wrong in my surmising, and if so, I'm sure a correction
> >  will be posted.
> >
> >
> >  73 de Les Smith
> >  vk2bcu at operamail.com
> 

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