P25 portable homebrew repeater

This forum is for discussions regarding System Infrastructure and Related Equipment. This includes but is not limited to repeaters, base stations, consoles, voters, Voice over IP, system design and implementation, and other related topics.

Moderator: Queue Moderator

Post Reply
gmilhouse
New User
Posts: 14
Joined: Wed Feb 04, 2009 7:12 am

P25 portable homebrew repeater

Post by gmilhouse »

Hi everyone!

I want to build a UHF repeater that is transparent, just like the maxtrac ones. I don't really have access to GM300 or maxtrac radios here in Australia because they are pretty rare and expensive. I need 440Mhz with a 5Mhz split.

I have several UHF mobile radios available in the right split but I am not sure how to connect the whole thing up. This is what I thought might work but please correct me if I am wrong.

RX audio taken from discriminator and fed to TX radio after the pre - emphasis cct. Wire both radios to have a common gnd. Connect the TX PTT to gnd via a active low COR point in the RX radio.

Have I missed anything?

Thanks

Greg
VK2VGM
MattSR
Posts: 770
Joined: Mon Apr 21, 2003 10:00 pm

Re: P25 portable homebrew repeater

Post by MattSR »

Sounds good Greg. We did the same thing be rewiring a CDR700 to use the "Rx disc out" and "Flat Tx inputs"

Worked a charm after we got the levels right!
Post Reply

Return to “Base Stations, Repeaters, General Infrastructure”