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SOLAR POWERED MAST-HEAD AMPLIFIER
DESIGN IDEA:
As solar panels are now plentiful and cheap,
why not use them as a freestanding power supply for your masthead RF signal amplifier?
I have a couple of remote powered masthead amps currently in use.
They amplify weak 144.825 Mhz sigs' from the
ISS
and 162 MHz
A.I.S.
maritime data transmissions
They need only 10~30mA operating current. Reference:
A suitable solar cell.
Stand-alone solar powered masthead amp.
Stand-alone solar powered masthead amp, with remote LED indication of current flow from solar array into circuit
You will have to run additional "supervisory" wire along with coax to enable (remote) LED
Stand-alone solar powered masthead amp,
with remote LED indication of current flow from solar array into circuit.
If LED extinguished; switch over to battery power.
Now the reverse-biassed LED will also block any supply current flow back thru darkened solar cell!
The gain
of the amplifier is variable; by adjustment of the collector load - being
a 1KΩ "pot" in the power supply.
In use, I have noticed the MAR6 can
mix strong off-air signals and self-oscillate (i.e. 'taking off').
By
adjustment of the load pot, this condition can be avoided - listening for
clean audio from receiver,
and noting the value of current, which gives
nil self-regeneration!
Another idea: remote voltage display monitors potential at masthead amp'
Power supply is isolated by reverse-biassed series diode: that prevents current drain from solar cell.
When no sun.....voltage drops off: switch on power supply to supply masthead amp.
Solar cell is then isolated by reverse-biassed series diode,
despite Solar cell shows high MΩ resistance when non-illuminated.
Use PIN diodes (1N5817) because of lowest forward voltage drop (0.15-0.45 volt)
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