Motorola GR1225 cooling fan upgrade

[dana13898]

I read in a post that GR 1225 radios used as a repeater, should be set to 25 watts to prevent overheating. Someone suggested installing a better cooling blowing outwards.

Can I get a recommendation on the make-model of such fan and where to purchase please?

My radio in currently set at 45 watts and the fan is on the thermostat setting. It occasionally comes on while the radio is idle.

The repeater is only use occasionally by me and my wife for brief chats.

The radio is connected by 75’ of LMR 400 to an Omni directional 9db gain antenna. GMRS usage.

That will change soon to a ridged coax when I move the antenna to a Rohn 40’ tower.

Thanks

 

[prcguy]

I read in a post that GR 1225 radios used as a repeater, should be set to 25 watts to prevent overheating. Someone suggested installing a better cooling blowing outwards.

Can I get a recommendation on the make-model of such fan and where to purchase please?

My radio in currently set at 45 watts and the fan is on the thermostat setting. It occasionally comes on while the radio is idle.

The repeater is only use occasionally by me and my wife for brief chats.

The radio is connected by 75’ of LMR 400 to an Omni directional 9db gain antenna. GMRS usage.

That will change soon to a ridged coax when I move the antenna to a Rohn 40’ tower.

Thanks

What size is the fan? Loose the LMR cable, not good for full duplex systems.

 

[Project25_MASTR]

Are you using a GR1225 or a pair of M1225's?

 

[dana13898]

What size is the fan? Loose the LMR cable, not good for full duplex systems.

I believe the fan inside the GR1225 is stock. I’d have to disassemble to measure.
I agree with the LMR upgrade. That’s in the planing stage too.
I gathering final pieces to set up a 40’ Rohn tower. I will run solid core coax then. Thank you.

 

[dana13898]

Are you using a GR1225 or a pair of M1225's?

It is an actual GR 1225 base station repeater UHF GMRS freq

 

[jeepsandradios]

If your running the GR1225 at 45 watts into LMR you wont need a fan shortly. While the fan will help you really need to lower the power or you will replace it. I worked on many of these units back in the shop days. Even radios sitting on a bench withmultiple fans blowing on them would die with frequent use. The only GR1225 I still have in service since new is a the lp version thats hooked to a external PA. AS for fans I've tried about a dozen. In he past digi key was theo nly answrr but now with jungle site just measure size and order something. If its the table top version you can't really add more fans. I would also change it to blow continuous and not on thermister.

 

[dana13898]

If your running the GR1225 at 45 watts into LMR you wont need a fan shortly. While the fan will help you really need to lower the power or you will replace it. I worked on many of these units back in the shop days. Even radios sitting on a bench withmultiple fans blowing on them would die with frequent use. The only GR1225 I still have in service since new is a the lp version thats hooked to an external PA. AS for fans I've tried about a dozen. In he past digi key was theo nly answrr but now with jungle site just measure size and order something. If its the table top version you can't really add more fans. I would also change it to blow continuous and not on thermister.

Thank you for the great information! I appreciate your knowledge.

I will turn down the power as soon as I get my Windows 7, 32-bit computer up and running this week so I can actually program it. I have the software and cable already.

Fortunately for me the GR 1225 doesn’t get much use. It’s powered up from 8-5 and used sporadically by me and my wife.

I set the output power to 25 watts asap.

It I disable the repeater, pressing the repeater button, does the unit simply become a desk model base station? I can reach another GRMS repeater approx 12 miles away on another freq.

Again, thanks!

 

[Project25_MASTR]

If you disable the repeater, it effectively becomes a split base station that just receives on 467.xxx MHz and transmits on 462.xxx MHz. It wouldn't be frequency agile due to the duplexer but if you ran separate transmit and receive antennas it could be frequency agile.