[Milsurplus] Navy MBM photo

[Mike Morrow]

Hue wrote:

> For updating your Navy catalog pages, here is an image
> of the rarely > encountered Navy type MBM CAPI-43066
> transmitter-receiver.
>
> Manufacturer: Jefferson Travis
> Year of production: 1945 only
> Production: at least 157, this unit's serial. 
> Weight: 20 lbs ( trans-rec unit only ) 
> Freq range:  4-7.5, 7.5-14 Mcs.
> Modes: receive A1 A2 A3, transmit A1
> Emission power: 20-12 watt; lower power on crystal harmonic.
> Transmitter, 6V6, 6L6.
>
> Employment: coastwatcher and forward operations in Pacific War
> theater
> Power: handcranked generator, or internal 6 volt storage battery
> in Power Supply  unit (not shown ), or external 6 volt battery.
> 
> 4 screw holes at 4 corners receive the fasteners for the waterproof
> lid. 3 composite units are supplied in luggage-style suitcase:
> radio unit; power-supply with internal battery; handcrank generator.
>
> Right 1/3 of radio pictured is storage area for spare tubes, crystals,
> headphone, key.

The description in the Navy Type Number Catalog

 http://www.virhistory.com/navy/manuals/nt/NT-900109-3.43.rcvr_xmtr.pdf

differs (and is obviously incorrect) in some interesting details.

CAPI- 43066 MBM
RADIO TRANSMITTER-RECEIVER: 
FREQUENCY RANGE 4·14 MC IN TWO BANDS
(4-7.5, 7,5-14). POWER OUTPUT ON A2 IS 
l5-20 WATTS BETWEEN 4-7.5 MC AND 6.5·12 
WATTS BETWEEN 7.5-14 MC. RECEIVER OUTPUT 
IS 5OO MW INTO 600 OHM PHONE.  CONTINUOUS
TUNING EMPLOYED FOR RECEPTION AND FlXED
FREOUENCY CRYSTAL TUNING IS USED FOR
TRANSMISSION. JACK ON PANEL IS PROVIDED
FOR PLUGGING IN REMOTE TELEGRAPH KEY.
RECEPTION IS A2 & A3.
01/20/1945 MBM UNIT 1
FEB. 1945

That description indicates NO capability for A1 transmission or reception!  That would have been bizarre, were it correct.  Hue's picture shows a receiver "C.W. ON/OFF" switch and "C.W. PITCH" control.  The type number manual description should have shown exactly what Hue wrote.  The manual for the MBM is NAVSHIPS 900,581.

It would be interesting to have a collection of these late-WWII unusual-purpose small HF sets like the AN/PRC-1, AN/PRC-5, AN/TRC-10...and now the MBM.

Is the set pictured in your collection, Hue?  Very interesting...thanks for showing it.

Mike / KK5F
(Does anyone have any info on the MBN, a.k.a. AN/PRC-7(XN-1)?)