Batboard

I hope this is not Off Topic for this section, but I gotta start somewhere. I am supply comms for a large event here in Australia in a few months time. As a part of this we need to communicate directly with our police friends travelling with us. We usually provide them with a Gm300 UHF radio, magnetic base antenna and away we all go.

Now they have gone over to Astro Digital, and they will not allow me to put a Gm300 UHF in their vehicle unless I can give them a 100% guarantee (they haven't said in writing but I expect to have to do that too)that it will not upset their nice shiney new radio or the police network.

Haven't struck this before, don't know if I can work around it..

Any suggestions group ?

To be honest, I thought if anything was going to upset something else, their Astros would upset my GM300's !!!

For what it's worth the frequency difference between us will be around 5 mhz

Thanks in advance
Mike

Analog or digital makes absolutely no difference in matters of interference. Any on-air signal is subject to interference one way or the other. If frequency 'A' did not interfere with frequency 'B' when they were both analog, then introducing digital into the mix won't make a lick of difference. Your 5MHz spread between frequencies should be more than adequate, providing you don't sit the antennas immediately next to one another. The more seperation, the better. As far as a 'guarantee' that interference won't occur, nobody can guarantee that. You can only take all the steps to try & ensure it won't occur (mainly, frequency & physical seperation).

Todd

wavetar wrote:Analog or digital makes absolutely no difference in matters of interference. Any on-air signal is subject to interference one way or the other. If frequency 'A' did not interfere with frequency 'B' when they were both analog, then introducing digital into the mix won't make a lick of difference. Your 5MHz spread between frequencies should be more than adequate, providing you don't sit the antennas immediately next to one another. The more seperation, the better. As far as a 'guarantee' that interference won't occur, nobody can guarantee that. You can only take all the steps to try & ensure it won't occur (mainly, frequency & physical seperation).

Todd

Thanks for that Todd,
I have had almost nil experience with digital radio so I wanted to be able to go into bat with my system with some advance knowledge.
We have used the same radios (Gm300's) with their analogue radios for the past 5 years and NEVER had a problem. They are utilising basically the same frequencies (a few khz out) as they have used in the past, and we are using basically the same frequencies as we have used in the past.

The unknown (X factor) for me was do the digital radios behave in the same disgraceful was as 800mhz Digital GSM phones emmiting RF garbage to anything within a very short distance.

Off to talk to the Police .......

Thanks again
Michael