Specifications

Page 7
Copyright 2006 Robert A. Larson, KC9ICH
DC CONVERTER, MODEL 14A
For 12-14 volt DC operation in mobile installations, it will be necessary to use the Siltronix 14A Converter. The Model 14A D.C.
Converter attaches to the rear of the Model 1011D transceiver and converts it to 12-14 volts D.C. input. The 14A D.C. Converter is
for normal negative ground systems. Two No. 6 sheet metal screws must be used to attach the 14A firmly to the transceiver.
The Model 14A is conservatively designed for long reliable service with a minimum failure rate. It is designed for easy access and
servicing when required. The 14A may be detached quickly from the transceiver and tested individually, thus isolating the source of
trouble. It uses two power transistors for switching in a flip-flop oscillator circuit. They are rated at 50 amperes, with a 40 volt rating.
Diode spike clipping provides protection against one of the common sources of transistor failure.
The 12 volt electrical system in an automobile will sometimes generate high voltage transients. These can be caused by the starter
motor, the alternator or generator, or loose wiring, representing a serious hazard to the transistors in your DC power supply.
It is strongly recommended that the following checks be performed before operating the 1011D.
1) Clean and tighten the battery terminals and clamps.
2) Tighten battery cables where they attach to the starter solenoid and engine block.
3) Inspect battery cables for corrosion or wear. Replace them if their condition is questionable.
4) Check battery condition frequently. If the cells do not hold a similar charge or water level, replace the battery.
5) Check alternator or generator, and regulator connections for security. Also, primary ignition wiring, horn wiring, lights, etc.
6) Check the charging voltage from the alternator. Often the regulator is mis-adjusted, and the voltage setting may be
excessive. It should not read more than 14.5 volts at normal engine speeds.
Recommended wire size depends on length. For runs up to 5 feet, use 10 gauge. For 5 to 10 feet, use 8 gauge. Fuse should be
rated for 30 amperes, and may be in-line cartridge style, or insulated block holder. The fuse should be located near the battery
end of the cable. The transceiver DC cables should be connected directly to the battery.
MOBILE ANTENNAS
The standard type mobile antennas designed for 10 meters or CB band will perform well with the 1011D. Generally speaking, a full
length, 8 or 9 foot whip will be more efficient than the shorter inductively loaded types.
MICROPHONE
The microphone input is designed for high impedance microphones only. The choice of microphone is important for good speech
quality, and should be given serious consideration. The crystal lattice filter in the transceiver provides all the restriction necessary on
audio response, and further restriction in the microphone is not required. It is more important to have a microphone with a smooth,
flat, response throughout the speech range. The microphone plug must be a standard 1/4 inch diameter, three contact phone type. The
tip connection is for push-to-talk relay control, the ring connector is the microphone terminal and the sleeve is the common chassis
ground.
The microphone manufacturer’s instructions should be followed when connecting the microphone cable to the plug. Either
hand-held or desk type microphones with push-to-talk control will provide a suitable installation.
ACCESSORY OUTPUT JACK
A miniature jack on the rear panel, labeled “FD-1011 ACCESS” is provided for connection of the Model FD-1011 Digital Frequency
Indicator which is available from Siltronix distributors and dealers. Consult the instructions furnished with the FD-1011 for its
connection to the 1011D and its operation.
AUXILIARY RELAY JACK
Connections to the microphone push-to-talk circuit are brought out to the rear panel mounted AUX RELAY jack. The jack is a
standard RCA audio connector that is insulated from the chassis. The center connection is connected to +12V and the shell is
connected to the microphone keying circuit. Connection to the AUX RELAY jack permits simultaneous keying of the 1011D and
accessory units such as a linear amplifier, coaxial relay, etc. on.
CAUTION
Use an insulated cable for interconnecting the 1011D and the accessory unit. Guard against a metal objects making contact between
the connector shell and the chassis as undesired keying of the transmitter and accessory unit will result.
CAUTION
The current limit for the aux relay power source is 80 ma. Make certain that this limit is not exceeded or internal damage to the
1011D circuits may result.