[aprssig] I'm brainstorming, so don't beat me up!

Keith - VE7GDH ve7gdh at rac.ca
Sat Jul 9 15:02:33 CDT 2005

Earl KD5XB wrote on 08/07/2005

> As long as we're brainstorming, why not move from FM to SSB?

If you are talking about VHF APRS, that would drastically cut down on the number of people doing it because far more people have FM VHF radios than have SSB or multi-mode rigs. Also a nice thing about FM is that you can have multiple transmissions on the same frequency and the "FM capture effect" will often allow the receiving station to copy the strongest signal. Not always the case, but... 

If we all moved to SSB, it would not work as well as FM. With no "capture effect" in the receiver, the receiving TNC would be trying to deal with multiple beacons at the same time and it just wouldn't be very workable. Just take a listen on SSB sometime. If two stations "double" you will probably hear both of them.  With FM when there is a double, if one is significantly stronger than the other, you will just copy one. Of course, if the frequency is a bit off on one of them and it isn't significantly weaker than the other station, you will hear a heterodyne as well.

There's nothing wrong with brainstorming, but for now, I think FM is a good choice both because of equipment availability and for technical reasons.

73 es cul - Keith VE7GDH
"I may be lost, but I know exactly where I am!"

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