7
The RF cables should not be excessively long, although they are not critical.
1.5 HOME OR FIXED INSTALLATIONS
Mount the amplifier in any location that is cool, and has air circulation. It is best to mount this
unit with the long length of the heatsink fins vertical. For extended duty, you may want to add a
cooling fan.
The amplifier should be mounted as close to the power supply as possible. Section 1.2 details
wiring considerations.
The power supply should be fused or have internal current limiting at a maximum current of 35
amperes. It should be well filtered and voltage-regulated at no more than 15 volts dc. A power
supply with a crowbar or over-voltage protection system is a good idea, in case supply regulators
fail.
Be sure to ground the case of the unit to the station ground buss with a heavy short lead.
Lightning protection is a good idea, but the safest solution is to disconnect all antennas and
unplug all equipment when not being used.
2.0 RADIO OR EXCITER
This amplifier will work with almost any exciter or radio operating between 140 and 150 MHz.
The most important guidelines are detailed in the following sections:
2.1 DRIVE LEVEL
The radio or exciter used to drive this unit should have an output power between ½ and 10 watts.
Do not drive this unit with more than 12 watts on FM, 2 watts carrier on AM, or 5 watts PEP on
SSB (about 2 watts average power).
2.2 DUTY CYCLE
The duty cycle of this unit is primarily limited by heatsink temperature. The more power output
and hotter the ambient temperature, the more important cooling becomes. See section 1.1
2.3 T/R CONTROL OR “KEYING”
This unit contains an internal RF sensing system. This system will automatically disconnect the
receiving pre-amplifier (if being used). It also places the unit in a transmit-mode when the
POWER
switch is
ON
.
The rear-panel female phono (RCA) jack labeled
RELAY
can be used to manually force this unit
to switch into a transmit mode. If the
PRE-AMP
switch is on, the pre-amplifier will be switched
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