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Thread: 2 radios to one antenna 800mhz

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    Default 2 radios to one antenna 800mhz

    Got a project that im trying to work on.

    Got a local dispatch center that has a 800 mobile radio at a console hooked to an outside antenna. They want to add a second 800 mobile but do not want the hassle of a second antenna.

    Could a combiner work?


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    No unless both radios are on fixed frequencies. if they are trunked then you wont be able to do it.

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    For anyone who is thinking of adding a control station combiner, we looked into that, and those tend to take a separate transmit and receive antenna, and don't take kindly to being put through a duplexer. The amount of loss you put up with is ridiculous.

    The definition of experience? Trying things like this and realizing facts later on.

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    There *are* such devices as control station combiners that would fit the bill for this (dBspectra makes one, for example). The issue is that they are extraordinarily expensive. A few of our customers have some 6-port units, and have 6 trunked consolettes on 1 antenna.

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    The hassle of a second antenna is way less than trying to do a combiner that works properly for trunking radios. Plus as an added bonus you get a back-up system that keeps working in case of a primary system failure *free of charge*. Just make certian the antenna installer put the antennas at least 30' apart.

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    Am I the only one who thought "2 girls 1 cup", after reading "2 radios, 1 antenna"?

    :P

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    Quote Originally Posted by Mars View Post
    Am I the only one who thought "2 girls 1 cup", after reading "2 radios, 1 antenna"?

    :P
    You are, unquestionably, the only one who thought that. ****ing perv.

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    haha.

    well at least we know what was for lunch.

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    We have used the control station combiners for several jobs now, they work great if you are close to a site, if not the loss can be a problem.

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    Yes, it could work. What type of mobile radio is being used? Is the idea to use both radios at the same time on the same channel/group/ frequency?

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    No, One was mainly to be a receive. But needs to be able to transmit at times.
    and yes this is two trunking radios on same system being used as control stations. One is tied into a zetron dispatch console and the other is a standalone radio.

    Looks like I might have to do an antenna.

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    If possible mount the other antenna as far away from the other antenna as possible.
    Have you looked into a system where 2 consoles could use 1 radio?


    Quote Originally Posted by medic550 View Post
    No, One was mainly to be a receive. But needs to be able to transmit at times.
    and yes this is two trunking radios on same system being used as control stations. One is tied into a zetron dispatch console and the other is a standalone radio.

    Looks like I might have to do an antenna.

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    Way its set up now. One stays on a hospital medcom channel and the other scan some ems/fire talkgroups and can transmit on them.

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    For emergency communications I highly recommend 2 antennas. If the cost is a factor you may be able to run a (arrggg) mag mount or some other type of antenna to the second radio. There is also the option of using a BDA this would eliminate the linitation to just the 2 radios and would allow legit personell to use the system inside your facility.