On 01/01/2023 8:16 PM Doran Platt <[email protected]> wrote:

The VHF air ground band was defined by the SCR-522, the VHF SCR-274N, and the BC-639 and BC-640 system. All used the frequency band of 100-156 Mhz.  The BC-639/BC-640 system, along with DF antennas were used for fighter direction and general DF use. The a.c. powered SCR-522 was present, also. I will look at my ER article for better recall. The K39 trailer, etc., housed various numbers of the above. Channel spacing was fairly wide, those days. It wasn't until the aeronautical conferences in the late 40's and into the 50's that 100 kHz spacing came about. From there 50 and 25 kHz channels in the USA. Europe now has even closer spacing, 12.5 kHz.   I'm unsure how the Navy ARC-1 and the ARC-4 figure in all this but belive are either war end or post-war items.

Jeep K3HVG

On 01/01/2023 11:16 AM MARK DORNEY via MRCA <[email protected]> wrote:

Hello Everybody,

       I need you experts in the MRCA to get good information on this. Mike Potter is one of the folks putting together the Watch Station at the Military Aviation Museum in Virginia Beach, VA. These folks want to get this right. 

 If you get the chance, I highly recommend a visit to MAM Virginia Beach. 

The MRCA membership is far more qualified to answer Mike’s questions than I am.  And it is a different and  very interesting radio subject conversation for the MRCA membership to discuss. 

From: mike potter <[email protected]>
Date: January 1, 2023 at 9:46:48 AM EST
To: Mkdorney <[email protected]>
Subject: Radio bands in USAAF use WWII

HI, Mark

Hope this finds you well, and a very Happy New Year to you.  I saw you pop up with your command car discussion and wanted to ask your opinion on something.

One of many items on my "Goxhill items that need better understanding" has to do with radios.  We know from a list of airfield call / code words that Goxhill's codes were "Midmorn Point to Point" and "Heatwave VHF / DF".  

I've reread the Air Ministry's AP 3024 having to do with various  communications bands and their range and use in the RAF (and USAAF), and I've cobbled together the statement below that I hope is both concise and accurate, but I'm not enough of a radio guy to have confidence in that.

Would you please look at this and tell me if it seems reasonably accurate?

5. Radio Call signs list “Goxhill MIDMORN Point to Point, HEATWAVE VHF-DF” What are these distinctions?  Is one for telegraphy and the other telephony?  Morse vs. VHS?  When “Midmorn” and when “Heatwave” and for what purposes with what equipment.  Suggestion is that “Midmorn” is all voice traffic and “Heatwave” is Direction Finding only for lost aircraft(?)