Would like to setup a small tinker around repeater

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KG4LHQ
Posts: 642
Joined: Wed Sep 29, 2004 1:50 am

Would like to setup a small tinker around repeater

Post by KG4LHQ »

Hello,

I picked these cans up in a lot of other stuff that I've been selling around here and there and would like to see what I can do with them.

I'd like to maybe setup a small project repeater with maybe 2 radios or something and would like your advice.

Once again this is just a project repeater, nothing too fancy or anything just something to tinker around with. I apologize on the size of the pictures but I'd like for you to see exactly what I have, what I can do and is there any value in these and if so what?

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Would this work satisfactory on 2 GM300's or something, what radios will do repeating features or what. I have some knowledge about radios and stuff but when it comes in this area my mind is pretty gray.

Any and all help is greatly appreciated.
KG4LHQ
Posts: 642
Joined: Wed Sep 29, 2004 1:50 am

Re: Would like to setup a small tinker around repeater

Post by KG4LHQ »

Wow, 82 views and no help...
John
Posts: 387
Joined: Sun Sep 09, 2001 4:00 pm

Re: Would like to setup a small tinker around repeater

Post by John »

I am not a repeater expert but it appears what you have is a VHF duplexer. The frequencies are marked on the labels. What it will allow you to do is connect both a transmitter and receiver to the same antenna. The rest of the repeater functionality would have to be handled by something else. There is info on this board and othe places about connecting 2 GM300 or other similar radios together with some simple cables to get some of the basic functions but they are limited and don't have a lot of protection for the radios.

The duplexer would have to be used with the same frequencies shown on the labels unless someone has retuned it. Retuning takes special equipment such as a tracking generator and spectrum analyzer (and some skill).

Hope this helps.

John
motorola_otaku
Posts: 1854
Joined: Tue Jan 13, 2004 7:03 am

Re: Would like to setup a small tinker around repeater

Post by motorola_otaku »

You have a pass-reject duplexer. It should work fine on 2 meters with a 600kHz split, but since there are only 4 cans I wouldn't push more than 100W through it. Anyone with a tracking generator-equipped service monitor should have no problem tuning it for you.

If you decide not to keep it you can fetch ~$400 on eBay for it easy.
davidgcet
New User
Posts: 3
Joined: Tue Aug 31, 2010 1:00 pm

Re: Would like to setup a small tinker around repeater

Post by davidgcet »

yep, those are VHF pass-rejects and can be tricky to tune for 600khz offset if you are not patient or well equipped. you tune each side to pass it's appropriate freq, then tun the little gold caps to reject the other freq, then if necessary repeat until you have about 80-90db rejection on each side. i just tossed 4 sets of these in the trash last month, we had not further use for them. BUT i can say we used them as VHF combiners on a 3 mhz split for 2 paging TX for years, ran continuous 200 watts thru them with no issues.
ka8ypy
Posts: 279
Joined: Fri Jan 27, 2006 4:18 pm

Re: Would like to setup a small tinker around repeater

Post by ka8ypy »

davidgcet wrote:yep, those are VHF pass-rejects and can be tricky to tune for 600khz offset if you are not patient or well equipped. you tune each side to pass it's appropriate freq, then tun the little gold caps to reject the other freq, then if necessary repeat until you have about 80-90db rejection on each side. i just tossed 4 sets of these in the trash last month, we had not further use for them. BUT i can say we used them as VHF combiners on a 3 mhz split for 2 paging TX for years, ran continuous 200 watts thru them with no issues.
If you decide to throw any more away, let me know.

DB
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