Phantom RX Channel 28

[exapp]

Hello, Just installed a new Raymarine 49e on a sailboat. Didn't get a chance to do a full radio check with the coastguard but did a quick check the marina office and all appeared OK.

Thing is when i do an all channels scan i get a phantom RX on channel 28 with interference noise (buzzing). There was a fluorescent light by the galley and when this was turned off the buzzing was very much reduced. I turned absolutely everything else off on the boat except for the VHF and still the same.

Any ideas? Bad antenna install ??

Exapp

 

[Beadle]

If radio check ok I wouldn't worry too much

Probably someone somewhere had a carrier on 28 which opened the squelch on the receiver which in turn picked up the noise from the florry because the carrier was weak and the receiver would be working at full gain.

I can't remember if 28 is used for some sort of service transmission, or what its proper use is, can't recall having used it myself.

Do a radio check with a station some distance away, bet you find everything's fine.

 

[VicS]

Another fluorescent lamp on a nearby boat?

Ch 28 is a duplex channel that was a public correspondence channel. May have been used by one of the old coast radio stations. Some of those frequecies are now being used by the coastguard.

Thought i recognised it. It was one of Niton Radio's frequecies, but other stations used it as well. Cromarty, Whitby, Anglesey.

A check with the CG website did not show it as being used by them.

 

[earlybird]

I once purchased a Navico VHF and set it up with a spare aerial, on a window shelf at home, (over-looking the sea ), to try out the reception. It had constant interference on ch28, and wouldn't scan past this channel without turning the squelch right down. At first I suspected Anglesey CG, who are in range. Finally, I traced it to the set itself. If I moved the set from alongside the aerial to the back of the room it stopped. No problem when installed with a masthead aerial. My un-informed guess was that the design used an oscillator near that frequency. Maybe Raymarine is similar.