Howdy,


The SCR-508 was not designed to replace the SCR-506.  Both were in development around the same time, and the SCR-508 was actually standardized before the SCR-506.  Rather, the two sets were intended for different roles.  There was a need for a short-range (e.g., 10 miles) crystal-controlled, tactical mobile FM set for use primarily in tanks, as well as a longer range HF vehicular radio capable of at least 50 miles range on CW or 20 miles on AM voice.  The SCR-508 was used primarily for inter-tank communications and liason with artillery groups using the artillery band SCR-608 FM sets.  They were simple to use and required minimal operator training.  The SCR-506, operated mainly in CW mode, was used primarily for communicating at the division command and admin net levels and required trained radio operators.  Relatively few SCR-506s were installed in tanks, and those that were, were used for communicating back to battalion and division level nets.   


The WWII FM sets were state-of-the-art and unique to the U.S. forces, and were a radical improvement in mobile tactical communications.  The SCR-506 was also a pretty advanced design for its time.  The disparaging remarks about the 506 in amateur publications stems from its limited frequency range (and the limited viewpoint of hams), which includes only one amateur band.  In fact, the SCR-506 was an excellent, well-designed set that did just what it was designed to do.  


It's gratifying to see a youtube video on the important but completely overlooked subject of wideband FM tactical radio and its great effect on the course of WWII.  A fascinating episode not mentioned in the video and which demonstrates this, took place during the Battle of the Bulge.  As mentioned, the German tank sets were AM, and an airborne AM jammer system code-named "Jackal" had been developed to jam them.  However, the German AM sets and American FM sets overlapped in frequency, so commanders were unwilling to deploy Jackal for fear of jamming U.S. tank forces along with the German.  Armstrong urged them to proceed on the basis of the AM interference rejection capability of the wideband FM SCR-508 sets.  The Jackal jammers were installed in B-24s and flown in relays over the battlefield.  POW interviews conducted after the battle indicated the jamming seriously disrupted German communications, contributing greatly to the American breakout.  SCR-508 operators were unaware that jamming was even taking place...


73,


John K9WT



On 2/1/2026 1:09 PM, Ray Fantini via Milsurplus wrote:
I am always up for  watching videos on YouTube! But I do have a question about the use of the SCR-508 and its use in Operation Torch in North Africa. My limited understanding was that the SCR-506 (BC-652 and 653) being a HF AM set was replaced by the SCR-508 (BC-609 and 603) with its improved semi VHF and FM modulation.
Always speculated that for use in North Africa the older 506 would have been used being it was already out in production and in the field along with SCR-193 and 177 (BC-312 and BC-191) sets? And the Newer better FM sets were only just being deployed?
By the time we get to the Sicilian and Italian campaigns and defiantly by the time of Overlord but not ready for deployment during Torch.
There is a relevance to all this. In the military vehicle preservation world there has been some controversy over the appropriate radios for things like M1A1, M3A1 Scout Cars, M2A1 or M3 Halftrack and M29 Weasels along with M2A3 tanks.
One school of thought is it has to be a SCR-508 in one of its many configurations or its not correct, the problem is that the SCR-508 family of radios is just about useless in today's world. Where as the SCR-506 HF AM can be used on the modern Ham bands.
In the world of military vehicle collectors and restorers you have two groups, one group that stuffs the appropriate radio according to documentation on the vehicle regardless of its functional state, some go so far as to strip out the guts of the radios and stuff in things like CD players. The other camp are into functionality, we not only want it to look good but also preform somewhat along the lines of what it was intended to do.
One of my favorite justifications for the SCR-506 is that it's what we started the war with. OK, by the end of the war FM was king but in the beginning of the war the AM was all that was in the field. Also have to admit that I have always had a warm spot in my hart for the SCR-506 after reading in the 1948 CQ Surplus conversion manual that the SCR-506 was basically five hundred pounds of nothing.

Ray F/KA3EKH

From: [email protected] <[email protected]> on behalf of Mike Feher <[email protected]>
Sent: Saturday, January 31, 2026 12:36 AM
To: 'Charlie L.' <[email protected]>; [email protected] <[email protected]>
Subject: Re: [Milsurplus] New video - 13 mnutes
 
CAUTION: This email originated from outside of Salisbury University. Please exercise caution when clicking links or opening attachments from external sources.

Great video, Charlie. Thanks for sharing. 73 – Mike

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

908-902-3831

 

From: [email protected] <[email protected]> On Behalf Of Charlie L.
Sent: Friday, January 30, 2026 10:24 PM
To: [email protected]
Subject: [Milsurplus] New video - 13 mnutes

 

 

Thoughts?

 

Charlie, W4MEC in NC


Virus-free.www.avast.com 

______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
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