Ramsey Electronics FR146 manual Receiver Sensitivity, Adding An Led Power On Indicator

Models: FR146

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Further alignment now consists of adjusting the oscillator coil L3 to permit the tuning control (R1) to cover the 5 MHz. segment between 135 and 175 MHz of primary interest to you. Assuming you wish to adjust for the Two Meter 144-148 MHz Amateur Band, adjust L3 until you hear your intended test signal.

If you are a beginner with no license or other equipment, any Ham operator with a 2-meter transceiver should be willing to give you the test signal and extra help that you need. The FR146 is very sensitive, so operate the transceiver on low power on a simplex frequency from a distance of at least 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!

RECEIVER SENSITIVITY

Your FM receiver features sensitivity under 1 uv. Radio Hams constantly marvel at how an FR146 displayed at hamfests tunes in dozens of hand-held QSO's on the premises without an antenna connected! You can expect to monitor local repeater and simplex transmissions easily, using a simple groundplane style antenna. The receiver also responds very well to the addition of a low-noise pre- amplifier such as the Ramsey SA-7/PR-2. For 2 meters, the Ramsey PR-10, with its high-Q tuned circuitry and exceptional signal-to-noise ratio, offers significant performance improvement. A new and versatile receiver accessory is the Ramsey AA-7 HF-VHF Active Antenna, which doubles as a preamplifier with other antennas in addition to the excellent performance of its own whip.

ADDING AN LED POWER "ON" INDICATOR

For many people, a pilot lamp to indicate "power on" is more than a nice touch. They expect it and depend on it, reminding us that "real radios glow in the dark!" Adding a simple LED power-on indicator to your Ramsey kit receiver is easy. All you need is the LED itself and a small 1K to 2.2K resistor.

Study the PC traces between the positive battery supply wire and the on-off switch. The unused connectors on top of your switch are an ideal point to get the

+DC voltage needed for the anode (longer lead) of the LED. Plan where and how you wish to install the LED in your enclosure.

FR146 • 19

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Ramsey Electronics FR146 manual Receiver Sensitivity, Adding An Led Power On Indicator