[ARC5] ARR-1

[Brian Clarke]

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