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Commercial radio model

I have a KenwoodTM-271A commercial band radio I can't to transmit on m 150 MGZ frequency, even tho it receives on it. How do I determine the model number of these unit, and it is the wrong model, can I change it to transmit on my frequencies?  Thank you.

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Re: Commercial radio model


A Kenwood TM-271A is an amateur radio and therefore restricted to transmit only from 144 - 148 MHz but can receive from 136 to 174.

The TX restriction is done with a resistor (R119) which inhibits transmission outside of the 144-148 band. It is located very near a large IC (IC252).

Depending on your country's radio communications policies and/or your radio license privileges, simply removing R119 would allow transmission outside of the 144-148 MHz.

Hope this be of some help/idea. Post back should yuo need additional information.

Good luck and kind regards.

Posted on Oct 20, 2007

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Re: Commercial radio model

Simply Put, modifying an AMATEUR radio for use outside of the 144-148mhz band is completely illegal. These radios are not spec'd for operating in the commercial VHF Band, and modifying it to do so may cause not only failure of the radio, but when transmitting you may interfere with other commercial frequencies,, police, and if you are caught with the modified radio, may even face a huge fine or Jail time. Put bluntly, your better off to go out and purchase a proper VHF Radio for use in the frequencies which it is intended.

Posted on Jan 02, 2008

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Firstly, are you a licensed Amateur Radio Operator, if not, you are breaking the law buy transmitting on that frequency. The Amateur 2 metre band, which covers 144 - 148MHz is for the use by Licensed Amateur Radio Operators ONLY.

You are free to listen to these frequencies, because you are a listener, and the radio is being used to receive ONLY.

But you CAN NOT transmit on these frequencies.

If you get caught, you will be charged under federal FCC laws governing the use/misuse of radio equipment and a heavy fine &/or imprisonment can be expected. YOU HAVE BEEN WARNED!!!

Cheers, Peter

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