Ramsey Electronics FM10C, Руководство пользователя

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FM10C 21
USING THE FM10C WITHIN THE HOME
A most practical use for the FM10C would be to connect it to the main stereo
system within a large home so that whatever is playing on the main system
can also be tuned-in on portable FM radios in other rooms, the garage or out
in the yard.
This connection consists of using shielded audio cables to connect the auxil-
iary "line audio" output of your cassette deck, CD player or other stereo device
to the audio inputs of the FM10C. Consult the literature that came with your
stereo equipment.
Even if you intend only this limited convenience use of the FM10C for your
own home and family, it is still your responsibility, in accord with Part 15 of the
FCC Rules, to ensure that this operation does not cause interference to your
neighbors.
POWER SUPPLY CONSIDERATIONS
The FM10C is designed to operate from a single 9-volt battery mounted on the
PC board.
Whether an alternative AC adapter can be used depends on the quality of the
adapter and its ability to suppress unwanted AC-line hum. Various plug-in
adapters and power supplies in the 6 to 12 volt range may be tried, but make
sure the unit has DC output (positive tip) and is not merely a transformer relying
on rectifier circuitry within the device for which it was originally supplied as an
accessory.
L.E.D. "POWER ON" INDICATOR
Since the transmitter consumes power and emits RF whenever it is turned on,
a visual "on the air" indicator is desirable and is a fun enhancement of your
completed kit. If you are designing the FM10C setup for use by youngsters, a
flashing indicator is easily provided using our BL-1 "LED Blinky" kit. Voltage
for a standard LED is easily taken from the unused top terminals of S1. The
inner pin nearest the black lead of the battery cable is the +9 volt pin. The
ground can be taken from the black battery terminal, or the case of any of the
jacks, but it CANNOT be the antenna. This positive DC must be connected
to the anode (longer wire) of the LED. Use a 1K resistor in series with either
wire of the LED. The cathode lead is connected to the negative battery wire.
The resistor is omitted if you are using a 1.5 volt battery for prolonged short-
range operation.-