MSF 5000 external ampliifier

safuser · Post by **safuser** » Sun Feb 11, 2007 7:32 am

Is it possible to use a MSR2000 PA on a MSF5000? Is is possible to use an external VHF PA with a MSF5000? What would be required to interconnects?

Thanks.

bernie · Post by **bernie** » Sat Feb 17, 2007 7:29 pm

My two bits worth:
The MSF has a directional coupler in the out put of the amplifier ahead of the circulator. The reflected power is sensed by thermistors on the heat sink and circulator load.
The power control on the UNIBOARD controls the PA output by controlling the A+ to the IPA amplifier.

I have interfaced a Milicom 100W PA from a Desk Trac trunking repeater
to a 800 MSF trunking station..
I connected the directional coupler on the out put of the PA to the input of the
power control circuit. I used a connector that mated with the gray cable.
the control was touchy, but it worked until we got the proper amp.

You need to provide a feed back loop for the control circuit.
You could probably find a directional coupler (aka watt meter element)
in an old trunking combiner.

d119 · Post by **d119** » Tue Feb 20, 2007 8:20 pm

It's also possible to bypass the MSF power control sense line for use with an external repeater amplifier. I have an MSF 5000 configured this way so I can use it as a low power repeater. 12w out of the box.

Send a PM to user 'kgb' on here, he has the information.