Batboard

Hello thanks for lookginf here is the problem.

i have a vhf maratrac mounted in a 1996 chevy k3500 dump truck the antenna is mounted on the fender i did find i to have a bad cable so i put a temp mag mooun on thre roof when i put a meter on the radio nd key it down and it putts out 75 waatts (i have the radio turned down). after some use the radio stops putting out power. this alway seem to happen during the snow stirmn when the guys are talking alot.

i am putting on a new cable and a new Comtelco heavy duty with spring 5/8 on fender if the radio does this again is there any thing i can do to make the radio no give up i do have spar radio but it is an older radio with out stat aler mdc1200 that we use.

any help would be nice if the new antenna works i will lte u know all.

post a message here or e-mail me

thanks

kit N1mcc

Sounds like the radio power set points are not correct, allowing the transmitter to run way too hot and the tempature cutback is kicking in. Also check each transistor mounting hardware for correct tightness.

Hi:

Keep in mind you have a very good and
Professional radio which can be turned
into junk real quick with the use of a
Mag style Antenna.

Chances are VERY high that the VSWR on the
Antenna is so high, its being reflected back
into the transmitter causing it to become very HOT, and the thermal protection circuit ( or VSWR protection )is being activated.

Personal Opinion: High-Power Radios and
Mag Mounts DO NOT MIX.

I even recommed using RG-223 / or RG142B/U
Teflon Coax when using any kind of High-Power
radio. I have seen a 100 Watt Mitrek MELT
RG-58A/U and the antenna was OK.

So, its very important to have the correct
antenna, good coaxial cable, and make D*M
sure the VSWR is low as possible....100 Watts
foward, 2-4 watts ( or less ) reflected OK

Failure to observe that will kill the transmitter, and if it should blow up, very
costly to repair.

MS