[MRCA] RCA AVT-111 Question

[B. Smith]

Actually during the mid fifties  at most small tower airports LF 
receivers were the norm, transmitters were rare on single engine private 
aircraft. The C-150 came out with various radios but nothing  that I 
would call "modern style".  :-)

Z

On 3/1/2014 8:53 PM, D. Platt wrote:
> On 2/27/2014 2:02 PM, Ray Fantini wrote:
>> AVR-20?, wasn't there some sort of old timey craziness about how you 
>> used HF to talk to the tower and the tower responded on LF? Maybe on 
>> the NDB? And where were you supposed to put those huge square boxes 
>> in your L3 Cub anyway? By the mid-fifties when the Cessna 150 came 
>> out it incorporated a modern style avionics bay so assume all the old 
>> HF AM junk was dead by then and VHF AM had taken over so that AVT/AVR 
>> stuff must have had a short life span back in the forties and maybe 
>> early fifties.
>>
>> Ray F
>>
>>
> Ray,
> You are correct.  There was a "tower common" frequency in the 3 or 5 
> MHz range that was used by the aircraft and received, typically, on a 
> tunable LF receiver.  RCA, Heath, Harvey Wells, and a bunch of others 
> made them. In the 50's, Narco came up with the venerable Superhomer 
> VHT-( ).  It had 5-8 transmitter channels and a tunable VHF receiver 
> with VOR converter.  It also had a "whistle tune" like the A.R.C. 
> systems.  The military had a VHF "tower common" of 126.18 (hence all 
> those crystals out there for that frequency). Its all a matter of 
> history after that.  Narco, King, Cessna, et al with the 90, then 180, 
> 360, and finally 720 channels.  A lot of radio equipment (and their 
> manufacturers) have gone to pasture in the process!
>
> Jeep - K3HVG
>