In the same years, when the Sony ICF-6800W was one of Sony's most successful
shortwave receivers, Sony presented a Air Band receiver in a design similar
to that of the CRF-1: the receiver has a stand to be operated in a tilted position.
The Sony ICF-8650 als als successor of the TFM-8600 has a similar shaped cabinet, the carrying
handle can be used as a stand to use the receiver in tilted position, the frequency
display will face the front in this position.
The receiver measures 27,5 x 8 x 21,2 cm. It is powered by
eight UM-1 mono cell batteries or from an external center negative 12V DC power supply.
On the frontpanel, You find the main power switch and the rotary volume control on the left
side. The power switch has a position to activate dial illumination.
In the middle of the frontpanel, the signal strength meter and the frequency counter window
will take most of the available space. The ICF-8650 comes with a frequency counter
with a red LED display.
The tuning knob is located at the right of the frontpanel. Two tiny pushbuttons
set the meter to desplay battery strength and activate the frequency counter.
Below the frequency readout, You find three tiny square pushbuttons acting as
band selectors for FM, MW and Air Band, next to it another four same sized buttons
to select three frequency presets (the frequency is "stored" by the help of a little
thumbwheel operated potientiometer below the frequency memory chart with some
space to write down the station's / airport name) and to select manual tuning
in the fourth position.
The telescopic antenna is located at the right small face of the receiver, it
can be erected to vertical position; at the back of the radio, You find
jacks to connect earphones, a cassette recorder and an external 12 V power supply
as well as screw terminals to connect an external AM and FM antenna and earth.
The operation scheme of the ICF-8650 is uncomplicated.
When the bandranges FM and MW are active, You can use it as standard FM and mediumwave radio.
In the AIR position, the receiver can be tuned to signals from the Air Band
located above the VHF FM broadcast band. Although it's a VHF range, the transmissions
from nearby airports (weather reports) and air-ground / ground/air communications
are in amplitude modulation (AM) mode.
As most of these transmissions are short and there are long intervals without communication,
You can use the squelch function to suppress the continuous hiss from the speaker,
it will only be opened when a carrier is active on the frequency. Use the
squelch control below the signal strength meter to adjust squelch level.
The ICF-8650 is a special receiver for people interested in aeronautical
communications and it has probably been sold only in small numbers in Europe. When it was
new, You needed a special license to receive Air Band communications here in
Switzerland and in Germany, restrictions were even more stringent, so that even
the possession of such a receiver was not allowed.
The ICF-8650 is a very nice item in the collection and a rare classic when You stand at the edge
of an airfield or air show and can monitor the communications. Later Sony had
the ICF-2001D / ICF-2010 with Air Band coverage
and the AIR-7 / AIR-8 as special scanner receivers for offer.
© Martin Bösch 26. Sept. 2010 / transl. 14.11.2010