Can it be done to shorten one?
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Can it be done to shorten one?
Not a good idea. You will screw up your SWR.
What is "SWR"?
SWR is "Standing Wave Ratio" which is a measure of the antenna's match to the transmitter frequency. For an antenna to work well, it needs to be electrically the same length, or some major even fraction of the length, as the electromagnetic wave. With VHF centered around 157MHz, the wavelength is just about 1.9 meters, so an antenna needs to be 1.9m, .95m or .475m long for best performance. Shortening the antenna could easily result in a 75% power reduction. There are tricks to shorten the antenna physically while maintaining the proper electrical length with coils, but that's a manufacturing choice, not an adjustment that can be made.
Do a search on Google, there are lots of info on "cutting a VHF antenna"
it is possible, may I ask why you want this done, have you had the radio on the meter to check the output,are you not getting the distance you think you should,
it is pretty easy to blow out the final transistors, and pretty expensive to fix in some instances, I have cut lots but never without having put it on the swr meter, watt meter. go slow have you tried to move the antenna arround, sometimes the ground plane in one place is better than another, roof top mount, trunk, or truck bed, lots to consider
I found a deal on one that is longer than I would like.
Don't cut it....if you do it will not be resonant to the frequency any longer.....your radio performance will suffer and you could damage the final output stage of your transmitter.
if it is longer than you want, there are several ant. with different load coils at the top or some at the bottom, are you going to put it on a boat?
if so there is a mount that lets you lay the ant. down and out of the way.
The bigest question is: What are using the antenna for? Receiving only or transmitting/receiving?
Thanks for the help guys but the seller never would respond.:mad: Looks like Santa is going to bring me what I want.:)