146mhz limitations on 100W radios

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azlooker
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Joined: Wed Mar 26, 2008 12:26 am

146mhz limitations on 100W radios

Post by azlooker » Fri Jun 13, 2008 12:47 pm

Hello IS, do you know if the 146mhz limitation is caused by the 100w PA? I have a bunch of 5300's with low power that go all the way down to 136mhz. If I remove the pa will I be able to transmit down to 136mhz.

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Intrinsically Safe
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Re: 146mhz limitations on 100W radios

Post by Intrinsically Safe » Fri Jun 13, 2008 8:30 pm

I am pretty certain you are correct. The extended PA on the 100W mobile limits the freq range to only go down to 146MHz.
You can remove the extended PA but I don't have any documentation on that. From there I am sure you should be able to go down to 136MHz.

I.S.
Sean Penn: Last year I went to Iraq. Before Team America showed up, it was a happy place. They had flowery meadows and rainbow skies, and rivers made of chocolate, where the children danced and laughed and played with gumdrop smiles.

willbartlett
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Re: 146mhz limitations on 100W radios

Post by willbartlett » Sat Jun 14, 2008 10:32 pm

So, The modification from 110 watt back to 50 watts is fairly simple. The lower frequency limitation of 146 mhz remains. Is there some way to get around this in software? my radio will program 145.11, for example, but I get a error with the radio when I try to go to that channel. Any thoughts?

Will

azlooker
Posts: 15
Joined: Wed Mar 26, 2008 12:26 am

Re: 146mhz limitations on 100W radios

Post by azlooker » Mon Jun 16, 2008 5:15 pm

if thats the case, then it must be a firmware limitation. I wonder if we were able to get a firmware update, if that would change things. I tried to get the guy in Texas to sell me a radio at the $150 price but he said no. So its still all guesswork for now.

Adam

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Intrinsically Safe
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Re: 146mhz limitations on 100W radios

Post by Intrinsically Safe » Mon Jun 16, 2008 10:11 pm

l don't believe it to be firmware. The same is firmware is used in the 50W mobiles as well. There isn't special firmware just for the 100W radios. I still believe it to be hardware releated. I don't if it is becuase the aircraft band (I think) is in high 130Mhz area or if it is because of type acceptance. I know the original 100W moibles could only be sold to federal customers becuase they were not type accepted by the FCC. I guess I haven't really looked at the new ones to see if they are or not.

I.S.
Sean Penn: Last year I went to Iraq. Before Team America showed up, it was a happy place. They had flowery meadows and rainbow skies, and rivers made of chocolate, where the children danced and laughed and played with gumdrop smiles.

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