Ramsey Electronics FR220, Инструкция по эксплуатации

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FR-220
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TESTING, ALIGNMENT AND ADJUSTMENT
To prepare the FR220 FM VHF Receiver for reliable monitoring
operation, you will need these basic tools:
❒
1. A useful 220 MHz VHF signal source.
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2. Hexagonal, non-metallic coil slug alignment tool for L3.
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3. Small screwdriver to adjust L4.
1. Signal source: This signal can be from your test bench equipment or
from a "live" source such as a local repeater. The "live" signals are best
for fine-tuning, but they also have that VHF communications character of
being fast and to the point. Good test bench signal sources include your
own 220 MHz transceiver, if you are licensed to use it, a signal
generator or grid-dip oscillator.
2. L3 Alignment Tool: If you do not already have a set of plastic or
nylon coil alignment tools and do expect to try further Ham radio or
electronic hobby projects, such tools are worth having and can be
found inexpensively at any electronics store including Radio Shack.
While a metal Hex key wrench can fit the coil slug, the metal itself
would damage the coil inductance drastically and therefore should not
be used. With patience and sandpaper, a useable tool might be formed
from a wood or plastic rod.
ALIGNMENT PROCEDURE
❒
1. Make sure the power switch is off.
❒
2. Connect the antenna, earphone or speaker and battery.
❒
3. Turn the slug of L3 until it is even with the top of coil the form.
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4. Now, turn the slug of L3 clockwise 7 turns back into the form.
❒
5. Turn the slug of L4 until it is flush with the top of the coil and then
turn it 2 turns back into the coil.
❒
6. Turn all three controls to the left, fully counterclockwise.