Band Splits

[N9VU]

I'm a Ham Operator using 3 different types of Moto gear at the present time, and am out for a 4th (P25 or MotoTrbo). I've been told by a friend that it's very important I go for a rig that's within the bandsplit of about 403 - 470mhz in order to bring it into the Ham Bands for programming. How important is this, and can radios that have a low end rating of 450mhz - xxx still be converted with no performance issues?

[N4KVE]

A P25 radio will work fine in analog down to 440, but will not xmit in digital below 450. A Trbo 450-520 radio will work fine between 440-450, digital, or analog, but the programming sequence is a pain. You can never read the radio. You have to modify the saved codeplug, & write it back to the radio. GARY

[ki6yop]

N4KVE that is incorrect, all of my S split(450-520) p25 radios transmit perfectly fine down to 440 in analog and digital.

[N4KVE]

N4KVE that is incorrect, all of my S split(450-520) p25 radios transmit perfectly fine down to 440 in analog and digital.

Special tune, or factory tune? None I've seen will do that? How did you accomplish this? GARY

[ki6yop]

Nothing special, just modify the cps to allow the out of band frequencies and it works. No tuning has been done. This has worked on both astro and astro25 series radios.

[N4KVE]

Thanks. I learned something today. GARY

[N9VU]

Interesting. The reason I've asked this question is I'm seeing a number of mobile P25 and MotoTrbo units on the 450 + band splits going for less $$. Could it be due to lack of knowledge of the buying public?

[N4KVE]

In my personal experience with amateur 440 Trbo systems, those of us who bought used 403-470 XPR6550's paid between $400-$450 for them. However, those who bought 450-512 XPR6550's paid $300. They paid less because they can't read their radios, make changes, & program these changes back to the radio. Instead, they have to take their saved archive, make changes to it, & then reprogram these changes back to the radio. This is how these Trbo radios work with hex-edited Trbo CPS. It was explained to me that if they try to read these 450-512 radios that have 440 freq's programmed in them, the ham freq's will be lost. So because of the pain in the butt way the 450-512 radios need to be programmed in the 440-450 band, they go for less if sold to hams. I turned down one of these radios to get the correct "Q" split, & not have to deal with these programming hassles. It was worth it to me to pay the extra $100 to be able to program my radio the normal way. However, my friends who decided to save the hundred bucks by buying 450-512 radios are happy with the performance & they seem to work as well as the proper "Q" split radios. GARY

[n7maq]

Gary is correct in regards to Astro units, most of the time will not work in digital mode very far out of band. Astro25 units do not have this issue.


Jim

[N9VU]

Thanks gentlemen. I think the short end of it all is to get into a 403 - 470 band split rig. I already own 2 other Moto rigs where I can read and write to the rig at anytime, so much easier. That and the other issues with out of band sets just isn't as you say worth the $100 savings. Appreciate the advice.