AF-67 Trans-citer


SECTION 2

Installation and Operation

2.1 GENERAL CONSIDERATIONS.

No two installations being similar, the individual owner of the AF-67 Trans-citer will vary his installation according to space and operating practices. Regardless of these variations whenever the Trans-citer is installed in a mobile unit, there are two essentials that must be observed for proper installation:
  1. convenient location for operation, including ease of observation;
  2. rigid mechanical mounting.
The owner desiring to use the AF-67 as an exciter for higher powered equipment will have his own methods, etc. The usual standard practices for fixed or portable installations will suffice.

2.2 MOUNTING METHODS.

The construction of the cabinet on the AF-67 Trans-citer is such that it is readily adaptable to a hanging mount from the lower edge of the car dash board; or a fixed bottom bracket to the floor of the car. A brace to the fire wall will help make a more rigid installation. The AF-67 cabinet is equipped with felt feet for desk-top mounting in fixed or portable installations.

2.3 ANTENNA.

The ELMAC AF-67 Trans-citer will perform most efficiently when coupled to an antenna resonated to the desired operating frequency. Standard practices should be used for antenna relay control. Typical mobile circuits are shown on drawing #219, page 17, of this manual. The coaxial output connector serves as an output terminal for the transmission line. Coaxial connectors allow the installation of low-pass filters between the Trans-citer and the antenna or antenna tuners. The type of antenna depends upon the individual's preference. The following types of antennas can be directly fed from the AF-67 without an antenna tuner: Refer to the various handbooks on operating other types of antennas such as long wires, zepp fed, off center fed, lazy H, sterba curtains, phased arrays and the like.

2.4 T.V.I. PRECAUTIONS.

The ELMAC Trans-citer's circuitry is such that harmonics falling in the TV channels are at a minimum. The power plug leads are by-passed and other critical circuits designed for maximum harmonic attenuation. Under normal operating conditions the usual low-pass filter in the antenna transmission line, a brute-force filter in the AC power line, and a good efficient ground to the Trans-citer cabinet is sufficient to maintain a harmonic attenuation of 100 db down. Adequate shielding of stages and a completely shielded variable frequency oscillater make this possible.

2.5 POWER SUPPLY REQUIREMENTS.

For maximum flexibility the AF-67 Trans-citer power input is arranged for one or two (*) separate high voltage supplies. Filament input is arranged for either 6 volts @5.2 amp. or 12 volts @2.6 amp. AC or DC. (Refer to Drawing #219, page 17, for proper connections). Plate supply required: 500 volts max. @160 ma, and 250 volts max @75 ma

(*) Any single high voltage supply may be used with a dropping resistor as determined from the graph on page 13 of this manual. Any supply delivering 350 to 500 volts @235 ma. plus the proper filament voltage will suffice.

For mobile operation the power supply of the PMR6A receiver may be used for the 250 volt supply and the usual dynamotor for the higher voltage supply. By using the receiver power supply for the low level stages the drain on the dynamotor is minimized resulting in more efficient dynamotor operation. More high voltage at a lower battery drain will be realized. Refer to drawing #219, page 17, for typical circuits.

2.6 CONTROLS.

Sufficient controls have been incorporated for maximum flexibility, at the same time keeping operation simple. (See drawing #217, page 15).
Bandswitch
Switches all circuits to the desired amateur band simultaneously.
Meter switch
A 6 position meter function switch
  1. Final grid current, Final off.
  2. Final grid current, Final on.
  3. Final plate voltage, Final on.
  4. Not used. Final on.
  5. Modulator plate current, Final on.
  6. Final plate current, Final on.
Load control
Controls final load to antenna.
Plate tuning
Resonates final tank circuit.
Grid tuning
Tunes final grid.
Power "on-off" switch
Turns filaments on or off in a mobile installation, also controls primary power in an AC installation.
VFO switch
Connects VFO to receiver power supply for zero beating a carrier.
Mike jack
Microphone and push-to-talk circuit connections.
Key jack
Key connections for CW operation.
Crystal socket
Will hold two crystals in FT 243 holders.
VFO-Crystalswitch
Selects either variable frequency operation or operation from either of the two crystals inserted in the socket above.
VFO control
Variable frequency oscillator frequency control. Reads directly in megacycles.
A.F. Gain control
Controls per-centage of modulation or frequency deviation when using NBFM.
AM-NFM-CW switch
(On rear of chassis) Selects either amplitude modulation, narrow band frequency modulation or Al emmission.
High-low slide switch
(On rear of chassis) High position for crystal or dynamic microphones, low for carbon microphones.

2.7 POWER SUPPLY CONNECTIONS.

A 15 prong plug is used for all connections and various possible combinations are diagrammed in drawing #219.