Checking a radio’s alignment-transmit

Checking a radio’s transmit function. Both power and deviation.

1. Check radio’s Power Out

  • A portable radio should be 4 or 5 watts out
  • A mobile – depends on the model

2. Check the “frequency error”

  • With the IFR on “receive” and the correct RF frequency typed into the IFR, key up radio. Frequency error meter should be “0” (or the center of the scale).

3. Check Modulation

  • Turn the “Meter” knob to 6
  • Key up and say the word “FOUR” very loud into the microphone
  • You want the level to be 4 to 4.5 on the scale.
  • FCC states that modulation level should never be over 5.
    (or 2.0 to 2.5 on a narrow band radio).

4. Check the P.L. (private line tone)

  • “Horizontal” knob – turn to “Tone.”
  • You want to “Stretch it out” by using the tone generator “VAR” knob.
    (The tone button may have to be depressed for this operation)
  • Check that the “internal” switch is “on”.
  • MD should be 1.5

You want to get a stable circle on the monitor.IFR 1200 PL tone spectrum (see picture)

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