[Milsurplus] Japanese Midget Submarine Radio

[Mike Morrow]

BTW, if you go to http://babelfish.yahoo.com/

and enter the web site URL http://www.yokohamaradiomuseum.com/navy1.html
in the "Translate a web page" section and select "Japanese to English"
and hit TRANSLATE, you'll get a usable translation of the text on the
Japanese site.

For example, this is what it says about the midget submarine transceiver:

--- start quote ---
It is the radio equipment and material for special travelling in disguise
boat sea dragon 蛟 dragon loading which was developed in great war final period.
At the beginning, the radio equipment and material which is used with the shell
target (equipment and material name obscurity) with loading the identical
equipment and material was planned, but production was not in time, repaired
the “portable special telegraph” somewhat and came to the point of equipping.

Frequency: 5,000-10,000kHz
Radio wave type: A1 (telegraph), A3 (telephone)
Transmission input: 60W
Transmitter: As for crystal 叉 main oscillation UZ-42 and power amplification
UY-807A, first grid modulation UZ-42
Receiver: Superheterodyne system, the high frequency 1 step and the intermediate
frequency 1 step, it is low the frequency 2 step, 8 sphere systems, UZ-6D6 x7
and Ut-6B7 x1
Power source: Auto-converter, output; High pressure 750V and low pressure 250V
Antenna: As for the sea dragon the stick type antenna (the cylinder shape of
same approximately 1m as the shell target), as for the 蛟 dragon the opposite
V type by the stick type antenna or the happening falling down type mast
--- end quote ---

Not perfect...but certainly more than I could get from the original Japanese.
I can tell now that the transmitter (60W, A1 and A3 modes) is a crystal-controlled
MOPA (42, 807) that is grid modulated (42).  The receiver is a superhet with one 
RF and two IF stages.  The set operates between 5 and 10 MHz.  It sounds like a
pretty good design for the era, and for the Japanese.

I'm now doubtful that this was the type of set removed from the Pearl Harbor
midget.  The Japanese Type D (Koryu) midgets actually had five-man crews.  The
Pearl Harbor subs were two-man Type A (Ko-hyoteki) midgets.  This radio set seems
to be too advanced for the Type A, IMHO.  But maybe.

Mike / KK5F