Manufactured by Sony Corporation, Tokyo.
In the same period as the ICF-6800W was launched, Sony presented an aeronautical communications receiver in a design similar to the CRF-1. For operation, the radio can be set in a tilted position with a set-up bracket.
The Sony ICF-8650W Air band receiver can be set up in a tilted position using a set-up bracket.
The set measures 27.5 x 8 x 21.2 cm. It is powered by eight UM-1 mono cell batteries, which are inserted into the battery compartment on the bottom of the receiver, or by 12 V DC from an external power supply unit with centre-negative connector.
On the front panel, you will find the main switch on the left, which also activates the illumination of the display instrument, the rotary control for the volume and, right next to it the slightly smaller squelch control.
To the right of the signal strength / battery instrument is the red LED frequency display. The wavebands are switched by small pushbuttons just below the display, in the AIR position three more buttons are used to call up one of three frequencies preset by means of a knurled wheel, and another knurled wheel serves as a tone control.
The main tuning knob is located on the right side of the front panel, two small buttons above it are used to activate the digital frequency display and to display the battery level.
On the bottom of the unit, next to the base of the telescopic antenna, there are screw terminals for an external antenna. On the other side of the battery compartment cover, there are jack to connect earphones and a tape recorder, and a soc ket for a centre-negative external 12 V power supply.
Operating the ICF-8650 is straightforward. First, batteries are inserted and the telescopic antenna is brought into vertical position. The receiver is switched on with the main switch, the volume is turned up half way, the squelch is usually set to 0. By pressing the buttons for FM and MW, the receiver can be tuned normally in the medium or FM broadcast band.
In the AIR position, the set receives the AM transmissions of aeronautical communications in the VHF range on frequencies above the FM broadcast band. Signals can be picked up from aircraft and also from nearby airports. Since these transmissions are often short-lived, the squelch control can be used to suppress the hiss during transmission pauses; on a known aircraft radio frequency, the squelch control is turned up carefully until the background noise disappears. As soon as the transmitter is active, the squelch opens and the conversation can be heard.
The ICF-8650W as a special receiver for aircraft enthusiasts was already a niche product during its production period. Due to the coverage of the FM broadcast band down to 76 MHz, the FM band used in Japan, and also of the aeronautical communications band, ownership and operation of the receiver was prohibited in Germany for many years. In Switzerland, possession of the radio was permitted, but the receiver could not be operated on the aeronautical frequencies without a corresponding licence (pilot, etc.). Accordingly, the number of sets sold is small in Switzerland and minimal in Germany.
Single conversion superhet.
The set is equipped with semiconductors.