155.8425 in a Minitor IV

[jmfirefighter20]

Hi Folks-

I have searched and cannot find a decent answer on this topic.....soooooooo.

Due to the Federal Narrowbanding mandate our primary dispatch center has decided to get off of the regional frequency and start their own channel of 155.8425....the Minitor II's obviously won't work with this change mostly because of the lack or crystals and tone reeds. They have decided to get a bunch of used Minitor III/IV's and have them narrowbanded and have two channels put into them (for a fee, or course from one of the "used pager vendors").

Now I have played with my Min IV and the software and have been unable to get the software to allow me to program in 155.8425 (Invalid frequency)....is there some sort of hack in the software that this company may be using to allow the pager to be programmed with this channel, or is it impossible and we're getting smoke blown up our you-know-wheres?


Thanks,
Josh

[SteveC0625]

That frequency is one of the new 12.5 "splinter channels" which are sandwiched in between the old 25.0 spaced frequencies which the Minitor III and IV were designed for. Those pagers were never intended to be able to be tuned to these more precisely spaced channels.

Now, that said, I suppose it is possible to program a Minitor III or IV to a frequency close to the new splinter channel and then fine tune it on the bench with a service monitor. My guess is that might work as long as there are no nearby transmitters on the adjacent channels. Any transmission on an adjacent channel will likely bleed into your pagers a little or a lot depending on power and geographic proximity. And I do not know how well the pagers would hold the tighter tolerances needed to keep it on frequency when a splinter channel is involved.

And, as soon as some "know it all" inserts the pager into a programming cradle and tries to change something, I suspect the fine-tuning will be out the window and the pager rendered useless.

Maybe the pagers from the used pager vendor will work OK. But unless you are willing to spend the buck to have your pager "tuned" by the vendor, field programming alone is not enough.

[escomm]

If you get the license issued under Part 22 (paging) you won't have to narrowband. That might be something worth considering.

[jmfirefighter20]

Escomm- Unfortunately it's not up to us, the PD runs the dispatch, and they have already done all the legwork with the local dealer/FCC for this....we're going to this channel, and we have no choice (we are a private company dispatched through the municipal service...we do what they want us to)

Steve- Thanks for the reply. I was afraid that the vendor was going to put in a close frequency and then bench tune it as close as possible. I spoke with them on the phone today as they wanted to confirm the frequency and tones to be put into a pager we are having repaired.....he asked me if the freq was 155.840, and I corrected him to the .8425 and he said "oh yes, I see that right there, my mistake." Part of the other problem with this is that we are dispatched (for now) on two separate frequencies (154.190 for one town and 155.8425 for two of the towns starting Jan 1st. Currently we are only on 154.190 until the new "town" channel is up) I wonder if this will effect the pager at all.

I've been trying to get the service to migrate to the Minitor V (as problematic as they may be with some things) but they don't like to spend money on things. Since this is how we get our calls, it's kind of important that the pagers are operating correctly and there is no "mickey mousing" going on. We currently send them out for repairs, but we have been handling all programming in house.

[SteveC0625]

Joshua,

Any chance you guys have NB compliant portables that can do QCII? Might solve your problem.

[jmfirefighter20]

We did get some of the federal grant radios but they chose the ICOM P25 radio (rather than the XTS2500s), I am unsure if they are QCII capable.....either way we don't have enough to go around for everyone so we still have the pager issue.

[mr.syntrx]

Icom's P25 radios will all do 2-tone, so it'll partially get you out of trouble.

If budget for new pagers is an issue, you could get some cheap 2-tone capable portable radios instead? The Icom IC-F3001 goes for about $179 and they're actually surprisingly solid radios for the money.