The Millen 92101 is an electronic impedance matching device and broad-band preamplifier
which is placed between a receiver and antenna system. The basic design originally
appeared in General Electric Ham News magazine at the end of 1946. In ham circles
this device was known as the R-9'er or Q5'er. Several articles on the R-9'er and
its variants appeared in both QST and CQ magazines in the late 40's and early 50's.
The Millen version used a single 6AK5 vacuum tube for the amplifier and utalized
a plug-in tuning unit which contains both the input and output matching coils. Input
and output impedance matching is possible via front panel tuning capacitors, which
form parallel resonant circuits with the plug-in tuning coils. Plug-ins were available
for 13-15Mc, 27-32Mc and 48-55Mc. It appears that Millen began producing this unit
in 1947 after the Ham News article. This unit is owned by Don Buska N9OO and is currently being used with a Millen-era National HRO-5TA1 receiver on 10 and 20 meters. Besides the standard ham band plug-ins Don also acquired one that was labeled for TV channel 3. |