Hi all, Here is a brain teaser-maybe someone can help out..
I have a local FD that we set up with a new pair and new repeater for theire operations/dispatch/page. Their old pair (output a little noisy with other traffic) we are now converting to their fire ground. What I would like to do is use the input of their old pair 465.xxx as their simplex fire ground between portable and dispatch. The base set up so far is a ITA200/CDM1250 to a 5db stick on thier 80 ft. monopole. This covers their district well.
Here is the clincher. The fd is insistant on repeating their fire ground for listening pleasure. What I mean by this is that all of their F/G ops would be simplex, but would pass through the repeater so that distant units responding and pagers could hear the f/g traffic. Not a bad idea,,,Here is the problem. They are using M4 pagers. There ops and f/g channels are both 460.XXX and the M4 will not go to 465.xxx.
QUESTION: Can i set up a dual radio (CDM1250) repeater at the base connected to the tone remote and have the base RX and TX on 465.XXX and tx on 460.XXX when tx from the base.
I would like to do all of this from HQ with one unit. I know stashing another repeater somewhere is an option, but the antenna and provisions are already at HQ...
Thanks, Rob.
P.S. Hope this makes some sense.[/img]
Help with combo simplex repeated fire ground.........
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Re: Help with combo simplex repeated fire ground.........
FMROB wrote:Hi all, Here is a brain teaser-maybe someone can help out..
QUESTION: Can i set up a dual radio (CDM1250) repeater at the base connected to the tone remote and have the base RX and TX on 465.XXX and tx on 460.XXX when tx from the base.
I would like to do all of this from HQ with one unit. I know stashing another repeater somewhere is an option, but the antenna and provisions are already at HQ...
Thanks, Rob.
P.S. Hope this makes some sense.[/img]
The only way your going to be able to do this is with 2 different radios. Make a standard repeater with the normal input on 465 and the output on 460. Then give dispatch a second radio like a control station that receives on 460 and transmitts on 465. You just need to make sure the license is correct. If they were already using this pair for a repeater, then there is no problem.
Jim
Transmitting on 465 as an FB2 or FB1 is beyond the scope of your license. You can transmit on 465 only under an FX1 authorization, and that is available only to control stations working through repeaters and either meeting the requirements for "small control stations" or going through the "minimum power required" calcs for full-size control stations. In short, 465 cannot be used for simplex transmissions from a base consistent with Part 90 rules.
Note that, despite how some read the recent NFPA "guidance," there is nothing wrong (or unsafe) in using a conventional repeater channel for fireground operations SO LONG AS your jakes are properly schooled in how to go to direct if they get in trouble and can't hit the repeater from a basement or other difficult spot. Since the portables and mobiles Rx on the same freq for either repeat or direct, they will hear a direct "MayDay" should it be broadcast. This is widely done in a number of large metropolitan Fire Departments (including Boston FD).
Note that, despite how some read the recent NFPA "guidance," there is nothing wrong (or unsafe) in using a conventional repeater channel for fireground operations SO LONG AS your jakes are properly schooled in how to go to direct if they get in trouble and can't hit the repeater from a basement or other difficult spot. Since the portables and mobiles Rx on the same freq for either repeat or direct, they will hear a direct "MayDay" should it be broadcast. This is widely done in a number of large metropolitan Fire Departments (including Boston FD).
Hi, Thanks for the replies.....
While some departments in the area operate on a repeater for their fire ground ops.....There is NO way we are going to do this.
Like I said, It will work....But not well. The F/G traffic belongs conventional, and we avoid any and all equipment failure and/or reception problems goinf thru a repeater, etc. etc.
The second part is In no way, shape, or form am I concerned about the license issues. the portables and mobiles will be tx'in the way they always have,,,,and with the base station being a mobile radio with an ITA2000 it to will not be a problem. (the only difference is the height now that it is on the tower) In which case I don't really care, b/c the base doesn't tx on f/g much at all and I have tuned down the power to about 10 watts with a 5 db stick. The co traffic is about 200+ miles away. We can hear them, but they can't hear us. They are licensed for a crap load more tx power and height. Sooooo it shouldn't be a problem.
With that in mind I am still wondering if it is electronically possible to use a rick set-up and interface a tone remote on the rx side of the radio and haxe it tx on the same frequency. Some how I think that the duplexer will cause a problem.
While some departments in the area operate on a repeater for their fire ground ops.....There is NO way we are going to do this.
Like I said, It will work....But not well. The F/G traffic belongs conventional, and we avoid any and all equipment failure and/or reception problems goinf thru a repeater, etc. etc.
The second part is In no way, shape, or form am I concerned about the license issues. the portables and mobiles will be tx'in the way they always have,,,,and with the base station being a mobile radio with an ITA2000 it to will not be a problem. (the only difference is the height now that it is on the tower) In which case I don't really care, b/c the base doesn't tx on f/g much at all and I have tuned down the power to about 10 watts with a 5 db stick. The co traffic is about 200+ miles away. We can hear them, but they can't hear us. They are licensed for a crap load more tx power and height. Sooooo it shouldn't be a problem.
With that in mind I am still wondering if it is electronically possible to use a rick set-up and interface a tone remote on the rx side of the radio and haxe it tx on the same frequency. Some how I think that the duplexer will cause a problem.