[ARC5] Anyone Know Anything About A Link Radio 230D Frequency Meter/Monitor?

[Christopher Bowne]

I came across this oddity while doing my basement/shack cleanout.  Think  I 
picked it up at NearFest/Hosstraders at some point, apparently for   $5.00 or 
less - someone had put that price on the front cover with a  permanent marker... 


It's a very tall (about 16")  and narrow   (about 8 inches square footprint) OD 
green  military looking portable  piece of test gear with a latched on front 
cover.  Front panel contains a  National style Velvet Vernier dial (made by 
someone else), a crystal  oscillator switch, a variable oscillator switch, a 
corrector knob, a  headphone jack, power switch, and a green pilot light.  A 
storage area  in the bottom of the cabinet contains a really long (at least 10 
feet AC  power cord)

The removable front cover contains a clip for  storage of a small telescoping 
antenna that drops into the top of the  cabinet, and a calibration chart that 
has the 0-100 range of the vernier   dial as the x axis, and percent deviation, 
from .01 to at least 1.1 as  the Y axis.  The cal curve is a steep V which hits 
zero on the Y axis  at 50 on the X axis.  50 is noted to be equal to 39.1 Mc, 
which is  apparently the crystal frequency (actually a harmonic), the 
fundamental  is in the 4 Mc range. No other information is provided by the 
chart.

I  turned it on today for the  first time, and it apparently is working  
perfectly, when I turn both oscillator switches on, I can hear a loud  clean 
beat note that I can get to zero beat at 50 on the dial with the  the corrector. 


I suspect it was designed to be used in setting  up a radio system, possibly FM, 
that operated on 39.1  Mc.  Unit was  made in 1945.  Maybe for an early low band 
FM police radio system?  Get  nothing even closely related on a google search 
for it.

Very  nicely made, high quality components, two small chassis behind the front  
panel, one for oscillators/detector and audio amp (4 tubes), and  another for a 
power supply with a 6X5 rectifier. If not anything else,  might be useful to 
power up a BC-221.

Anyone know any more about this thing?