Which Deviation for 900?

[John G]

Which is the most popular deviation used on 900? I hear a lot about using GTX's with no hardware modifications which means 2.5 KHz. I also hear about using 800 Maxtracs which, if used with the existing IF filters, means 5 KHz. The few 900 repeaters I actually know anything about all use 5 KHz. I was thinking it would be easier if most folks are going to use radios without hardware mods to use 2.5 KHz. I am working on a repeater using GE EDACS gear which will be 2.5 KHz. Of course, most radios meant for 2.5 KHz on transmit will easily do 5 KHz. Likewise a receiver with IF filters for 5 KHz will work with 2.5 KHz deviation. The only real problem comes when trying to use a receiver meant for 2.5 KHz on a system set up for 5 KHz. What does everyone else use?
Thanks

[RADIOMAN2002]

Most hams I have spoken to, say that unless the system you want to use is 5kc, leave the radio alone at 2.5kc.

[N9CZV]

2.5kc is the only way to go.


David Epley, N9CZV
Show Low, Az

[ka3idn]

90 % of the equipment is 2.5khz dev, if you try to go wide you will have a problem with the reciever pass band.
and you will also cut the no# of available channals in half!
jim
ka3idn

[WB6DGN]

Then there are those that try to compromise at 3.0 to 3.3 Kc. Totally unacceptable. The standard is 2.5 and it works well.

73 Tom KB5DPE

[kcbooboo]

I found that several GTX portables were actually coming up with about 1.75 kHz deviation, so I bumped them up to about 2.6 kHz with DPL. Our local repeater is also using a MaxTrac as a receiver and no one is close enough to use these radios on a simplex channel, so this slight compromise helps those operators who just don't talk loud enough.

My GTX mobile was also underdeviating when I got it, so it too was adjusted higher.

Lest you think my equipment is at fault, I checked the deviation with my recently calibrated signal generator and spectrum analyzer and everything seems to agree within 5%.

Bob M.