False Tone Detection PSR-600

[KR7CQ]

I have noticed that on my PSR-600, when monitoring certain hams on 2 meter simplex, the scanner detects false PL tones. On top of this, the tone detected varies with each transmission between two or three tones. I confirmed that these guys were not running a PL.

Any ideas?

 

[ecps92]

I've seen this with other scanners and have attributed it to

a.) PL being run on the input and being passed thru the Repeater
b.) The Audio of the person speaking trips the PL
c.) The power supply might be passing noise to be seen as a PL

I have noticed that on my PSR-600, when monitoring certain hams on 2 meter simplex, the scanner detects false PL tones. On top of this, the tone detected varies with each transmission between two or three tones. I confirmed that these guys were not running a PL.

Any ideas?

 

[dkf435]

If they are not encoding tone the tone display meters will bounce around along with variations in the transmitted audio and also quirks of each radio and noise in the radios power supply, some of this information and key up envelope was captured by the Motron radio Fingerprint IDer to fingerprint radios.

The tone decoders in these scanners are a lot more reliable then the old AIE and Opto units that I have but still will false some, still keep the old tone readers around because every once in a while you find some hams using a non standard tone on links.

David Kb7uns