I purchased a vhf maratrac unit with the 99 channel head and its works well with the exception of it wants to put out crazy power (150/175 watts) on a couple repeater frequency's like 145.310 and 145.450 minus - splits.. Every other frequency we have programmed into the unit (all are in the 146 range simplex and repeaters)are at about 100 watts output ?.. It does go up a bit to like 110/115 watts out on 147 also . Im running the rig now but we took the low freq's out as I was afraid id take the finals out .
Any ideas on what to look for or do to make it cover the whole 2 meter ham band ?
TIA
Dave N8DC
maratrac VHF question
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Re: maratrac VHF question
Sounds like you'll need the RSS to do a complete "replace PA" sort of tune-up of the power out parameters.
Re: maratrac VHF question
The logic board in a Maratrac or M-400 are electrically the same as a Maxtrac.
The operating system of the radio doesn't control the TX power and sometimes the Deviation when way out of band.
If you do a search about transmit power or power out (something like that) you will find posts about this problem.
I have worked on several Maratracs that do just what you describe.
Now and then I find one that doesn't do that, don't know why.
Maybe Motorola made different versions of the firmware.
Bottom line is there is a common "manual transmit power" modification.
A small POT, and 'couple resistors if I remember right. (I haven't done one in months)
They are a very good Hi-power radio, probably worth doing the mod.
I think there is even photos on how to do it on the Repeater-Builder website.
You might go thru the "power calibration" section of the alignment in the service selection of the RSS just to be sure
before you modify the radio.
But I am pretty sure its the manual mod that will be needed to fix it.
Either that, or stay above 146.000 mhz.
The operating system of the radio doesn't control the TX power and sometimes the Deviation when way out of band.
If you do a search about transmit power or power out (something like that) you will find posts about this problem.
I have worked on several Maratracs that do just what you describe.
Now and then I find one that doesn't do that, don't know why.
Maybe Motorola made different versions of the firmware.
Bottom line is there is a common "manual transmit power" modification.
A small POT, and 'couple resistors if I remember right. (I haven't done one in months)
They are a very good Hi-power radio, probably worth doing the mod.
I think there is even photos on how to do it on the Repeater-Builder website.
You might go thru the "power calibration" section of the alignment in the service selection of the RSS just to be sure
before you modify the radio.
But I am pretty sure its the manual mod that will be needed to fix it.
Either that, or stay above 146.000 mhz.
Steve K.
Re: maratrac VHF question
I looked on the repeater builder web site but didn't find the info I'm wondering if you can point me in the right direction.
Thanks
Dave N8DC
Thanks
Dave N8DC
Re: maratrac VHF question
For the manual PA tx power I think its
http://www.repeater-builder.com/maxtrac ... ntrol.html
Or if that doesn't get you to it, go to the Repeater-Builder.com website.
Scroll down and select Motorola
Scroll down and select the Maxtrac Radius GM300
Scroll down and select Maxtrac manual PA modification
The Maratrac and M-400 electrically really are the same logic board as the "5-pin" Maxtrac board.
Just different firmware, and longer pins on the interconnect plug.
http://www.repeater-builder.com/maxtrac ... ntrol.html
Or if that doesn't get you to it, go to the Repeater-Builder.com website.
Scroll down and select Motorola
Scroll down and select the Maxtrac Radius GM300
Scroll down and select Maxtrac manual PA modification
The Maratrac and M-400 electrically really are the same logic board as the "5-pin" Maxtrac board.
Just different firmware, and longer pins on the interconnect plug.
Steve K.