Frequencies?

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G0DJA
Posts: 110
Joined: Fri Mar 28, 2008 2:35 pm

Frequencies?

Post by G0DJA » Thu Apr 17, 2008 8:59 pm

OK, now I think I have this sorted but please don't laugh if I've misunderstood...

The video channel and the audio channel(s) are related to one another.

So, if I'm correct, the audio channel from a 1310MHz repeater is 6MHz or 6.5MHz LF of the video channel. Yes?

Which means that my radio which goes up to only 1299MHz can't hear it/them.

However, for a station on 1280MHz, or 1255MHz etc., the audio should be on 1273.5MHz for video on 1280MHz, or lower for lower frequencies, so I should be able to hear them?

Opening up the FM to 'normal' from 'narrow' should allow me to hear the FM audio channels from people I can see direct on video through my normal TS2000, or even get some audio on FM even if the video wont lock, maybe?

Please bear with an old electrical engineer before we get to the back porch, fly back and synch...

barryg4vwt
Posts: 3
Joined: Thu Apr 17, 2008 5:34 pm

Re: Frequencies?

Post by barryg4vwt » Wed Apr 23, 2008 11:36 am

Hi Dave,not sure why you would want to do it ,but if you set your TX going,put your HF receiver on 6 mhz , you will hear the sub carrier,only works if the 23cms TX and HF rx are close together.

Regards..Barry

G0DJA
Posts: 110
Joined: Fri Mar 28, 2008 2:35 pm

Re: Frequencies?

Post by G0DJA » Wed Apr 23, 2008 1:00 pm

Thanks for the reply and the idea, Barry, but I was thinking more of listening for the audio transmission from another station, rather than my own. :D

I also now think that I had it the wrong way round and the audio transmission is HF of the video carrier?

I think I need to do a Google search, or go to the library and read up a bit more on the audio channel frequencies.

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