Unusual frequency!

[highlandchatter]

Came across a strange frequency which definitely sounded like a broadcast radio station on 863.550 WFM on checking out the frequency the next day it was silent. Anyone got any ideas what I was picking up or where it was coming from?? I live in Oban.

[BK]

That's a PMSE frequency used by wireless microphones, maybe there was some kind of event or outside broadcast nearby?

[highlandchatter]

Thanks very much!! I couldn't understand what it was I was picking up??....I guess it must have been close by as the signal was really strong. I must have a listen again to see if it reappears . do you know who the most likely users of these frequencies would be??

[Obiwan]

Wireless Headphone frequency

[BK]

Wireless Headphone frequency

Yes, I was wrong about it being a PMSE frequency - wireless microphones do use it, but it's actually a licence exempt band which means devices like wireless headphones also use it. That would explain why it sounded like a broadcast station

[Minus1]

You don't say what radio you are using, but this is my post from 2013:

Are you using a Uniden UBC3500XLT / BCT15X / similar ?

Both get ghost signals from broadcast FM transmitters in this freq range
as a consequence of the First IF frequency of 380.7-380.8 (twice that is 761.4-761.6)
Subtract 761.4 to 471.6 from the apparent freq and you will get the real freq.

e.g.
88.3 appears at about 849.8875 WFM
90.5 appears at about 852.0875 WFM
92.7 appears at about 854.1125 WFM

I can't find a list of frequencies in Oban, but 863.55 would suggest around 102.1 MHz might be worth checking?

[paulears]

Don't forget that ch70 also has people using it for in ear monitors IEMs, so f it was a radio mic, then that would clearly be a single microphone's output, but IEMs would be a mix - mind you, the range is very short - 50mW or less, so often range in feet rather than metres. Plenty of users, even professionals where they've used up channel 38. We have channel 38 kit for radio mics, but run the IEMs (4 of them) in ch 70.