[Milsurplus] Convoy radios and the MBF

[Mike Morrow]

Robert wrote:

> The 115 VAC/VDC power supply for the TBY was built to allow usage of the 
> TBY on merchant shipping equipped only with MF and HF CW rigs.  Much of the 
> pre-war merchant shipping had 115 VDC systems.  It could talk to the TBS on 
> the escorts.  The little MBF was built to replace it.

The other issue that rules out the possibility of MBF use by anyone in WWII
except possibly in the very last days of WWII is its date of introduction.

The MBF is not even listed in the January 1945 SHIPS 242A (List of Naval Radio,
Radar, and Sonar Equipment).  The only date I find on the *preliminary* instruction
manual for the MBF is 13 June 1945 on an addendum sheet at the front.  It appears
to me that the earliest at-sea use of the MBF could not have been much earlier than
mid-1945.

BTW, both of the above cited manuals are excellent products that I got from from
Robert's catalog.  SHIP 242A is possibly the most useful historical document in
my library.

Ray wrote:

> Short of use on a museum ship why would anyone want a Collins MBF?

Well, it's a lot easier to put on 6m than is the BC-1000-A.  It's an
interesting design both electrically and mechanically.  It is "Collins"
after all, and prominently marked as such on the front.  But more generally
that raises questions like this:

Why would anyone want a ARA receiver that doesn't cover a ham band, or a
AN/APN-1 radio altimeter, or an ABK or SCR-695 IFF set, or a AN/ARW-17
guided bomb receiver, or a AN/APN-9 LORAN A set, or a ZB VHF homing set,
or even that BC-1000-A FM set?  Ask Jack Antonio why he went to the effort
of firing up his RT-45/ARQ-1 "Sandy" HF/VHF jamming set.  The whole subject
of radio equipment design and use by the military in wartime is fascinating
and much more educational from a historical and technical standpoint than
only that of the common gear that has or had direct ham-use capability.   

> Have seen them before and always wondered if this was the radio that would
> have been supplied to merchant vessels for use in convoys?

I think that is a very reasonable application, but only if the MBF had come out
a couple of years earlier.  Obviously the large multi-unit TBS sets would *not*
have been convenient to install on merchant shipping, or even smaller naval
vessels for which the MBF is ideal.  The MBF operates from 115 VAC or VDC.
Its power supply automatically configures itself...it doesn't even matter
what polarity is presented to two AC/DC power connector terminals.

> There is a MBF currently listed on that place, item # 140625412601

(Link http://www.ebay.com/itm/140625412601 )

It's quite remarkable for condition, but unfortunately it is missing the
unobtainable control covers (which the seller commendably makes very clear).
Also, the shock mounts have been removed and small pads of rubber substituted.
Otherwise it looks like NOS condition.  Hams almost always discarded the covers
on the MBF.  I have one MBF COL-43065 that is complete with all covers and shock
mount plate COL-10479, but it is the only one that complete that I've ever come
across.  I've never seen the COL-10406 accessory case that would have been mounted
above the RT unit.

Mike / KK5F