Frequency Question

[Renamon]

I have a question as seen below...

157.7775 <----Narrow Band
157.78 <----Wide Band
157.78125 <------------------------WHAT WOULD THIS BE CONSIDERED????
157.7825 <----Narrow Band
157.785 <----Wide Band

What would the benefit of using 157.78125 be over one of its neighbors. Also, I noticed that one of these "splinter" channels only happens every 6 frequencies.

-Jake

[Renamon]

Ok, I may have just answered my own question.

157.7775 <----C4FM
157.78 <----FM
157.78125 <------------------------CQPSK (P25 Phase 2 / 6.25kHz)
157.7825 <----C4FM
157.785 <----FM

That right, or am I way off?

[Renamon]

Doing more digging proves my last idea all wrong, so I'm back at square 1.

[akardam]

Where (and how) in all that is holy did you come up with those example frequencies?

[Renamon]

I was in the Astro Saber RSS and I was using the up arrow to change the freq, and I came upon the 157.78125 freq. So when posting this question, I just went "up" and "down" 2 times to get the examples.

I had ment to type 147.78, but typed 157.78 instead, and used the up arrow instead of left to go and correct the "5" and got 157.78125.

[akardam]

Those are all center frequencies for standard 25.0 KHz and 12.5 KHz spacings, which doesn't strictly indicate what modulation scheme or bandwidth is being used, although conventionally you wouldn't have a 25.0 KHz channel centered on a 12.5 KHz splinter. The Astro Saber is incapable of operating on a 6.25 KHz channel.