I work for an ambulance service that cover 430 square miles and about population of around 100,000 people. We have a VHF repeater system with a single site for transmit/receive for the majority of our coverage area, and another VHF repeater for the southern part of our coverage area. We use Motorola CP200 portable radios and we attach the remote lock/unlock for the ambulance to the antenna. What I am trying to research is if we are limiting the transmit range and/or the receive ability of our radios by zip tying the remote for the ambulance to the antenna. Although we may sacrifice some of the range, the majority of employees find the antenna as a great location for the remote. One of our ambulances is trying not having the remote on the portable antenna, but instead attached to a leather radio case. So if anyone has some antenna expertise I would be very appreciative.
Thanks
Antenna attachment affect range?
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Re: Antenna attachment affect range?
Simple answer is that anything that obstructs the radio antenna will effect range. It may have little effect, but may also have a significant effect. If you are have any range issues, one of the first things that I would do is it get rid of those remotes tie wrapped to the portable antennas.
Re: Antenna attachment affect range?
+1
Kinda hard to tell through the interwebs. If it works, fine, and if it don't, stop doing it.
Kinda hard to tell through the interwebs. If it works, fine, and if it don't, stop doing it.
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Tom in D.C.
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- Joined: Tue Sep 04, 2001 4:00 pm
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Re: Antenna attachment affect range?
Here is another "take" on the OP's question, not about range but something else.
Range questions aside, the fact is that hanging anything from a portable's antenna will change
the impedance of the antenna, just like grabbing the antenna with your hand will. In the long,
and perhaps the short, run it's not good for the final amplifier inside the radio due to the mismatch
that is created.
Range questions aside, the fact is that hanging anything from a portable's antenna will change
the impedance of the antenna, just like grabbing the antenna with your hand will. In the long,
and perhaps the short, run it's not good for the final amplifier inside the radio due to the mismatch
that is created.
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
Re: Antenna attachment affect range?
Not to mention that even at 5 watts, the RF from the portable cannot be good for they keyless entry.
Re: Antenna attachment affect range?
Thanks for everyone's input. I will post the end result of our month long test on one of our trucks. At this point it looks like we are going to attach the remote to the leather radio case.