GM900 UHF - minimum TX power?

g8tzl2004 · Post by **g8tzl2004** » Tue Jun 27, 2006 9:03 am

I have recently acquired a UHF GM900. The model number is M01RHK9AN3BN.

I have successfully programmed the radio but have a few questions:

- I did an internet search and the UHF GM900 appears to come in 2 versions : 1-10W and 10-25W (unlike the VHF GM900 which is 1-25W). My GM900 currently Tx's either 25W (high) or 10W (low). Is it possible to lower the mimimum TX power to ,say, 5W?

- In the Service RSS Transmitter section , there is a "High Power Range" option. There are 2 parameters : High Power Range and Low Power Range.

On my UHF GM900 , both parameters are set to "High". The Help Page says "....changing a setting to Low will allow a VHF radio to be tuned down to 1W . High Power Range sets power for the high power softpot . Low Power Range sets power for the low power softpot....."

I have NOT tried , but can I set the Low Power Range to "Low" on a UHF GM900 , so that I can lower the low TX power to 5W but still have 25W high power??? Or is the minimum TX power 10W's???

- my UHF GM900 was about 1.5Khz off freq. I tweaked the Ref Oscillator from a setting of "137" to "150" and now the radio is more or less on freq. Is it usual to find a UHF radio 1.5KHz off freq? ( I am aware of the GM300 off freq issue)

- the head on my UHF GM900 has an LCD display whereas my VHF GM900 has an LED display (L"E"D). Is it possible to use a "newer" GM900 LCD display on an "older" GM900 body?

Thanks

g8tzl2004 · Post by **g8tzl2004** » Wed Jun 28, 2006 7:17 am

Any thoughts on any (not necessarily all

) of the above questions?

Thanks

Post by **wavetar** » Wed Jun 28, 2006 7:36 am

Yes, you can adjust the high & low power parameters in the service menu, so you could have 'high' set for 25W and 'low' set for 5W, no problem.

It is not unusual to find a GM900/MCS2000 radio to be 1.5KHz off frequency, especially if it's been a couple of years since it was adjusted (if ever).

I do not believe you can swap the control heads.

Todd

g8tzl2004 · Post by **g8tzl2004** » Thu Jun 29, 2006 8:32 am

Todd - thanks very much for the feedback

Andreas · Post by **Andreas** » Sun Jul 02, 2006 9:38 am

I´ve never seen a GM900 with LED display.I only saw a CM360 and GM300 with LED Display.

Andreas

g8tzl2004 · Post by **g8tzl2004** » Sun Jul 02, 2006 12:32 pm

My "early" GM900 has illuminated green numbers and a black background display - it looks very much like my GM300 display.

My "later" GM900 has black numbers and an illuminated green background - it looks like a traditional LCD display.

Otherwise , both GM900 heads look identical.

Andreas · Post by **Andreas** » Sun Jul 02, 2006 12:46 pm

Ah,you mean the old inverted LCD.

Andreas