[ARC5] MF/HF "Command" Set Receiver History vs. Hacks By The Military

[Mike Hanz]

On 2/8/2011 7:37 PM, Mike Morrow wrote:
> Reference is made to BC-455-B receivers modified for VHF.  A few were modified
> to cover 28 to 41 MHz for the potential of using the German "Sonne" radio beacon
> system.  This was based on the pre-WWII German commercial "Lorenz" beacon system.
> [...] It would
> be interesting to know what organization made how many of these conversions,
> but the frequency dials were reported as re-calibrated for 28 to 41 MC,
> something not likely to have been carried out by any outfit performing a "hack".

I've seen photos of these dials and would have to agree they would most 
likely have to be made on the same type of engraving jig that ARC used 
for production models. That doesn't rule out ARC (or Western Electric) 
making them for the USAAF group that was credited with the receiver in 
question, of course.  It would have been good corporate policy to do a 
small job such as that for a big customer like General Arnold!  An 
angled jig with a divider head drive surrounded by an engraving 
pantograph like that isn't impossible to make with a good model shop, 
but finding such a capability in the ETO in wartime that had the time 
and priority to take on such a small job would have been a real challenge.

The rest of your e-mail is a great summary of the history of the set, 
and quite accurate from what little I know about it.

73,
Mike