440 Noise Update

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John Hogenmiller

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Jun 28, 2022, 1:18:33 PM6/28/22

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Sending this as a separate email after today's net.

We put a mixed analog/dmr 440 repeater at Kinton knob on the 444.2 frequency. For those that monitor 444.2, you will be hearing the digital DMR noise when that transmits. I don't know how many people monitor the 440.

To eliminate the noise, you need to put a Carrier Tone Squelch (PL Tone) of 123Hz on the receive. I will bring my programming cable to the meeting, or if you would like to drop off a radio I can reprogram it beforehand.

On baofeng, this is R-CTCSS, menu 11. Kenny reports that his showed confirmed, but didn't save it, and on mine I deleted the channel and recreated it. I'll put together the steps to do that on a keypad.

On older ICOMs, this is TON.TSQL (TONE, Tone Squelch)

On Kenwoods when it's just a transmit tone, it's "T", and when it's both, it says "CT".

Further background information:

This is an ongoing experiment as there are a number of club members interested in DMR but not in setting up a DMR raspberry pi hotspot. There's also some advantage to being able to use a DMR radio away from your QTH. We tried this at Martin Hill, but the coverage from the rooftop is not good. By putting it on Kinton, it gets the same coverage our existing 440 does. We were able to reprogram it while Dave was down yesterday.

People can get a DMR capable radio, program in the 440 frequency and talkgroups they would like to try. There's an active Cambria talkgroup and a Western PA talkgroup. If there's enough interest, we can request a Bedford talkgroup, which we could then have linked to our analog repeaters.