Checking a Radio’s Receive alignment and PL tone reception
Key the Rx frequency of the channel you are testing into the the IFR by depressing the “RF” button and typing in the frequency on the IFR’s keypads.
Put the IFR in “generate mode and generate a 3K test tone (if the radio channel is wide band)
- Note that you will have to generate a P.L. tone to make the radio open squelch.
There are two type of P.L. Tones:
- CTCSS (e.g. 179.9)
- DCS or Digital coded squelch, which is normally a three digit number.
Squelch should open up on a radio at around .2 microvolts.
- Note: to check a DCS P.L. tone, go to 2nd Function “DCS” button and use the +/- button to change between a “normal” or “inverted” P.L. tone.
Keying up will show the radio’s P.L. code.
Note: make sure the P.L. is turned on.