Ramsey Electronics FR220, Инструкция по эксплуатации

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FR-220
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7. Turn the power ON.
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8. Turn R2 (Volume control) until you hear some noise.
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9. Adjust L4 for maximum noise in the speaker.
Further alignment now consists of adjusting the oscillator coil L3 to
permit the tuning control (R3) to cover the 5 MHz segment between 222
and 227 MHz of primary interest to you.
If you are a beginner with no license or other equipment, any Ham
operator with a 220 MHz transceiver should be willing to give you the
test signal and extra help that you need. The FR220 is very sensitive, so
operate the transceiver on low power on a simplex frequency no closer
than across the room. An 8" piece of wire will be a sufficient receiving
antenna for such tests. If you don't know any Hams, visit a friendly two-
way radio service center to get close to the test signal you need!
If available in your area, TV channel 13 transmits the audio portion of its
signal on 215.75 MHz. If you can tune some semblance of channel 13
audio on your receiver, you know that a slight adjustment of L3 will bring
your receiver up into the 222 MHz ham band. You would turn the coil
slug CCW to increase its resonant frequency. Do not expect to hear the
TV channel's audio clearly, it's wideband FM (75 KHz) signal is too
broad for our narrowband FM IF filter.
If TV channel 13 is not on in your area, you can use a TV set to receive
the FR220's local oscillator signal. Connect the TV antenna to the
FR220's antenna jack, enough signal will "leak" out the antenna jack
and be picked up by the TV. You'll see the TV picture or sound go blank
as you tune. Remember that if you tune the TV to channel 13, it is set to
receive sound at 215.75 MHz, and if it is receiving the FR220, the
FR220 is actually set to receive 205.05 MHz (205.05 + 10.7 = 215.75).
Other TV channels near the FR220's tuning range
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Channel 13 Video: 211.25 MHz Audio: 215.75 MHz
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Channel 12 Video: 205.25 MHz Audio: 209.75 MHz
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Channel 11 Video: 199.25 MHz Audio: 203.75 MHz