Just a threaded stud with a knurled nut.



On 11/30/2025 1:03 PM, Michael St. Angelo via MRCA wrote:
What type of an antenna connection does it have?

Mike N2MS

On 11/30/2025 12:58 PM EST Al Klase <[email protected]> wrote:


There is a crystal socket to the side. There are also snap fasteners on the cover for the battery connection.
 
 
 
 I'm thanking it might have been some sort of test rig. Say, to be carried out on the flight line to adjust some avionic thing.
 
 AL
 

On 11/29/2025 8:50 PM, [email protected] wrote:

I don't see any XTALs and the selector switch has torroids
The 3B4 tube was first introduced in 1948 according to the release notice, so it was post WWII.


The more I look at it, the less it looks like a radio. maybe a metal detector chassis?
On Saturday, November 29, 2025 at 03:28:43 PM EST, Al Klase <[email protected]> wrote:





 
 
 
 Larger tube is a 3B4 (Gone to air)
 
 What is this?
 AL
-- 
 Al Klase - N3FRQ
 Jersey City, NJ
 http://www.skywaves.ar88.net/


 

______________________________________________________________
 MRCA mailing list
 Home: http://mailman.qth.net/mailman/listinfo/mrca
 Help: http://mailman.qth.net/mmfaq.htm
 Post: mailto:[email protected]
 
 This list hosted by: http://www.qsl.net
 Please help support this email list: http://www.qsl.net/donate.html
-- 
 Al Klase - N3FRQ
 Jersey City, NJ
 http://www.skywaves.ar88.net/


 
 ______________________________________________________________
MRCA mailing list
Home: http://mailman.qth.net/mailman/listinfo/mrca
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
______________________________________________________________
MRCA mailing list
Home: http://mailman.qth.net/mailman/listinfo/mrca
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

--
ARK Sig Block Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net/