[MRCA] SCR-245

Fri Sep 1 10:58:01 EDT 2017

Hello Ray,
     Way ahead of you on the vehicle thing.  I  already have a BC-654 
operational in my WC-52.  Next up is a BC-659, and  then perhaps a VRC-3 ( I have 
a WW2 BC-100, and the PP-114 I have is 1945  dated).  I'm just about ready 
with all three radios ( The BC-1000 will be  used only to monitor, due to 
band restrictions).  I wrote an article that  should be printed in either Army 
Motors or Supply Line on practical  installations of WW2 vehicle radios in 
vintage WW2 vehicles.   Basically, getting things to work is going to depend 
on standardization of  frequencies that the radios installed in the 
vehicles operate on.  I think,  for WW2 vehciles, for HF AM sets, 3885 KC is the 
way to go (works on the  BC-611, BC-1306 and BC-654), as it is already in 
popular use with the antique  military radio community.  "Jeep" radios ( by 
those I more mean radios that  don't take up the whole back of the Jeep) are 
also popular in the WW2  vehicle community.  In WW2 radios, that would be the 
BC-620 and BC-659 (  the BC 1306, BC-654, and the SCR-608 can be installed in 
Jeeps, but take up most  of the back seat, and eliminate access to tool 
boxes).  The BC-620 presents  problems pertaining to the frequencies the radio 
is capable of operating on, but  the BC-659 can operate on the phone section 
of the 10 meter FM band.  I  recommended installing the crystal for 29.6 
MHz as the "A" channel, since 29.6  MHz is the 10 meter FM simplex frequency.  
Making the "A" channel a  national (or International) standard makes it 
easier for everybody to talk to  one another.  The "B"  or "Talk Frequency" 
channel is more of a  challenge in that the phone section of the 10 meter band 
is pretty limited,  and you want to pick a frequency that doesn't interfere 
with local repeaters or  the 10 meter satellite uplink and downlink 
frequencies.  Here in  Dutchess County, New York, 29.1 MHz fm works, but it may not 
work for somebody  in another location.

    Another limiter for the older military sets is the  input voltage the 
power supplies need. If the power supply can't use the  voltage the vehicle 
it's installed in runs off of, that presents a  problem.  Most WW2  wheeled 
vehicles are 6 volt, with some  radio vehicles either coming out of the 
factory or converted in the field  to 12 volt.  I'm not familiar with the 
electrical systems in tanks,  but I wouldn't be surprised if some were 24 volt. 
Most aircraft were also  24 volt.  

Most WW2 power supplies are pretty bulky so room in the vehicle can  also 
be a problem.

Mark
WW2RDO

In a message dated 9/1/2017 9:29:53 A.M. Eastern Daylight Time,  
RAFANTINI at salisbury.edu writes:

Seeing that a BC-223 transmitter was offered up got me  thinking about the 
SCR-245 radio system. That’s the combination of the BC-223  transmitter and 
the BC-312 receiver to provide a low powered HF AM radio  system intended 
for tank, armored vehicle and command car use that was  replaced by the 
SCR-508 being a superior system for mobile operation being FM  and VHF. The 
SCR-508 was introduced around mid-41 with the HF AM SCR-245  coming out in 37 so 
there was a period of time before VHF FM was adopted for  vehicle operation 
but my question would be was the SCR-245 ever fielded in  combat? Was 
thinking that maybe it was used in North Africa if it were used at  all or was the 
SCR-508 in use by that time? If it was in use in North Africa  were all the 
vehicles with that installation overhauled to the newer radios  before use 
in Europe? What about equipment used in Sicily and Italy? Being  that was in 
between the two operations. 
The SCR-506 with its massive BC-653 transmitter and the  BC-652 receiver 
also fits into this roll somehow but always thought that was  more an 
artillery or more a command and control type radio being high power  and not 
intended in the small tactical role as the SCR-245 also I have noticed  that 
although I have only seen maybe two or three BC-223 transmitters before  the ones 
I have seen appear to have never been issued and perhaps that says  
something to if they were ever used or not. 
The relevance of all this is that in the last several years  I have noticed 
that I had moved away from the concept of having just one part  of a 
communications system and look at things more as a complete package.  Where it was 
once something to have just a receiver or maybe a transceiver  that I use 
on the Ham bands now looking at having complete systems and  operations along 
the lines of original intentions, at least without the  shooting part. In 
the last couple years the M151 with its VRC-12 and GRC-106  systems has been 
a lot of fun for use around the house or at shows but have  been thinking 
along the lines of what’s next and perhaps a field package of  the SCR-245 in 
a big wooden transit case may have possibilities? Who knows,  that may have 
to lead to a WW2 vehicle?  
Ray  F/KA3EKH

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