I need HELP with a Motorola GM300 UHF

james radio & supply · Thu Jan 10, 2002 4:19 am

I have a Motorola GM300 UHF 438 to 47-Mhz 1 to 10 Watt. Is it possible to get more watts out of it? It is set on 10 watts now. Some one said to change the PA board. Is this possible?

[ This Message was edited by: james radio & supply on 2002-01-10 07:19 ]

[ This Message was edited by: james radio & supply on 2002-01-10 10:10 ]

Will · Post by **Will** » Thu Jan 10, 2002 1:41 pm

James, I belive April answered your question on another board.
But to quote her, you can get 13 to 15 watts out of a LPI PA on UHF, but you need to reset ALL the softpot calibration points via RSS. Best to let a qualified tech. do this, I remember April said she would do it for you, that is a nice jesture on her part.
You can change to PA board if you can find one or change the whole PA assembly heat sink and all. You still HAVE TO recalibrate ALL the PA settings in the radio via RSS for the new PA.
Remember to change the serial tag of the radio to the new heat sink.
We put a note inside the radio when we do this to let the next technician know that the PA has been changed.

james radio & supply · Thu Jan 10, 2002 1:48 pm

Ok thank you. I think i am going to sale it and buy a 25 to 40 watt. It will be much easier for me to do.

Will · Post by **Will** » Thu Jan 10, 2002 2:03 pm

If you have a another PA then have April do the calibration for you.

Monty · Post by **Monty** » Thu Jan 10, 2002 3:15 pm

Hi:

If you have a Low Power GM300, I would
recomend " Against" running the Tx power
output beyond the range specified by the
Model number of the radio.

Getting a extra watt or two out of the radio
will make no differnece in range, but will
limit the life of the 10 Watt Power Amp.

If you wish, I can " Upgrade" your radio to
a 40 watt version for around 200.00 as the
entire PA has to be replaced, and the radio
Tx Soft Pot values need to be " Detailed" if
you want a good performing radio.

If you need more power, getting a 25 or 40
Watt radio would be ideal....and I do have
some 25 Watt GM300's and some 40 Watt Maxtracs if you are interested.

Also, another good alternative, is get a
40-50 Watt Power Amp....I have a few of those too and they require 10 Watts input
Dive for 40-50 Watts out...

Just to give you a few ideas

Monty

james radio & supply · Thu Jan 10, 2002 6:54 pm

Thank you for all the GOOD information. Also I have been told that if i put a 5bd gain antenna on this 10 watt GM300 that it will have the same range as a 40 watt maxtrac with a 1/4 antenna. Is this TRUE?

james radio & supply · Thu Jan 10, 2002 6:56 pm

Also what are you asking for one of the 40 to 50 watt power amps?

[ This Message was edited by: james radio & supply on 2002-01-10 21:57 ]

Monty · Post by **Monty** » Thu Jan 10, 2002 11:34 pm

HI:

I have a KLM 10-40W UHF Power Amp in Excellent Condition for 85.00 + S & H
if you are interested.

Great for those 1-10 Watt Series Radios.

Also, the use of a GAIN antenna is a good
choice too, as it helps the Receiver as well
as the transmitter.

I use alot of the 3+ Db gain MOSAIC Antennas
made by Antenna Specialist, and they work very well for a Low Profile antenna...If you
want one of the best, Motorola does make a 5 DB Gain antenna, and with a 100Watt maratrac,
a radio set up like that is tough to beat.

Monty

Email me direct if you need some additional
information @ [email protected]

[ This Message was edited by: [email protected] on 2002-01-11 02:40 ]