Emsflyer84 Posted December 2, 2023 Report Share Posted December 2, 2023 Hey all, I’m new to GMRS but been in the Ham game for a bit. Recently some of my buddies took an interest in GMRS and are getting licensed. I’m thinking of putting up a repeater at my house since I already have an antenna mount and coax cable up on my roof, where my current Ham antenna is. I’m looking for the most simple way to set up a simple repeater using one additional antenna on my roof. At the same time I can’t justify spending thousands just so my friends and I can chat. Looking at a few options. First is the Midland repeater-in-a-box: https://midlandusa.com/products/midland-mxr10-repeater Second is this gadget which I came across by accident, can’t find much info on it: https://kleinelectronics.com/flex-professional-repeater/ Third is this unit consisting of a couple Mororola radios. But I’m not sure if it has a duplexer or if I’d need two antennas. https://www.ebay.com/itm/285485485142?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=ZIH74GuxSLC&sssrc=4429486&ssuid=GJxbJs7qTe-&var=&widget_ver=artemis&media=COPY Any advice here or other suggestions would be idea. Simple and compact is what I’m going for here. The more “plug and play” the better. Thanks! Quote Link to comment Share on other sites More sharing options...
WRUU653 Posted December 2, 2023 Report Share Posted December 2, 2023 The Retevis RT97S looks to be similar to the Midland at somewhat less cost. I have no experience with either, perhaps someone who does will chime in. Quote Link to comment Share on other sites More sharing options...
Emsflyer84 Posted December 2, 2023 Author Report Share Posted December 2, 2023 I did see the Retevis and there were some good reviews and others who were let down with the power, etc. open to all options though. Quote Link to comment Share on other sites More sharing options...
WRYC373 Posted December 2, 2023 Report Share Posted December 2, 2023 Motorola Made some really nice repeater models for GMRS issue is theyre pricey and most are no longer in production. The RT97 repeater in a box is a great value just make sure you get the GMRS version. They make a few variants. Quote Link to comment Share on other sites More sharing options...
Emsflyer84 Posted December 2, 2023 Author Report Share Posted December 2, 2023 Thanks, I’m a little concerned over the power, it’s rated for 10w output but users say they are really only getting 3-5 watts. We’ll see. Quote Link to comment Share on other sites More sharing options...
WRYZ926 Posted December 2, 2023 Report Share Posted December 2, 2023 The power output is always lowered when using duplexers. Midland and Retevis state the total combines power of their repeaters. WRUU653 1 Quote Link to comment Share on other sites More sharing options...
hfd376 Posted December 2, 2023 Report Share Posted December 2, 2023 There will always be a transmit and receive power loss when a duplexer is used. Quote Link to comment Share on other sites More sharing options...
SteveShannon Posted December 2, 2023 Report Share Posted December 2, 2023 Welcome to the forum. I recommend that you start here: WRXB215 and Radioguy7268 2 Quote Link to comment Share on other sites More sharing options...
Radioguy7268 Posted December 2, 2023 Report Share Posted December 2, 2023 Those Midland/Retevis repeaters have a very small internal duplexer that can barely create any decent isolation when the repeater is cranking more than 5 watts. There is no magic bullet. You are never going to find a good, cheap, compact duplexer that passes 95% of your transmitter power and still gives you 90+ dB of isolation. It doesn't exist. Every rookie with a wattmeter wants to get the MAXIMUM possible output power out of their repeater. I mean, 50 has to be better than 5, right? In my opinion, the MOST important spec in a repeater system is the isolation between transmit and receive. Especially if you're using portable radios out in the field that can talk back in with 4 or 5 watts of transmit power. What good is it to key up your repeater with 10 or 15 watts of power when you introduce 3 or 4 dB of desense into the system? 3dB of desense on the receiver just made your 4 watt portable into a 2 watt portable, and how well is that going to work? Better isolation = a better repeater. Want to have a cheap repeater? You will get what you paid for. Cheap is rarely good. WRYZ926, gortex2, quarterwave and 2 others 5 Quote Link to comment Share on other sites More sharing options...
BoxCar Posted December 2, 2023 Report Share Posted December 2, 2023 1 hour ago, Radioguy7268 said: Those Midland/Retevis repeaters have a very small internal duplexer that can barely create any decent isolation when the repeater is cranking more than 5 watts. There is no magic bullet. You are never going to find a good, cheap, compact duplexer that passes 95% of your transmitter power and still gives you 90+ dB of isolation. It doesn't exist. Every rookie with a wattmeter wants to get the MAXIMUM possible output power out of their repeater. I mean, 50 has to be better than 5, right? In my opinion, the MOST important spec in a repeater system is the isolation between transmit and receive. Especially if you're using portable radios out in the field that can talk back in with 4 or 5 watts of transmit power. What good is it to key up your repeater with 10 or 15 watts of power when you introduce 3 or 4 dB of desense into the system? 3dB of desense on the receiver just made your 4 watt portable into a 2 watt portable, and how well is that going to work? Better isolation = a better repeater. Want to have a cheap repeater? You will get what you paid for. Cheap is rarely good. VERY TRUE WORDS!!! Quote Link to comment Share on other sites More sharing options...
WRYZ926 Posted December 2, 2023 Report Share Posted December 2, 2023 Well said @Radioguy7268 When my local amateur radio club decided on getting a GMRS repeater, we went with a Bridgecom BCR-40U repeater and we are using a separate duplexer that has been tuned for GMRS frequencies. Hopefully we will have the repeater installed at the tower and running in the next week or two. The GMRS antennas are around 400 feet up on the radio station tower. Quote Link to comment Share on other sites More sharing options...
hmurmur Posted December 3, 2023 Report Share Posted December 3, 2023 I am new to GMRS I subscribed to a GMRS repeater but having trouble programming into my new BaoFend UV5G I have input and output channels are the Input channels RX or Tx I know this is simple. thank you for the help Quote Link to comment Share on other sites More sharing options...
SteveShannon Posted December 3, 2023 Report Share Posted December 3, 2023 17 minutes ago, hmurmur said: I am new to GMRS I subscribed to a GMRS repeater but having trouble programming into my new BaoFend UV5G I have input and output channels are the Input channels RX or Tx I know this is simple. thank you for the help The repeater Input is the TX channel for your radio. It should be a 467.xxx MHz frequency. Quote Link to comment Share on other sites More sharing options...
Scottytalk Posted December 4, 2023 Report Share Posted December 4, 2023 It may not be the best option, but there is free software called, CHIRP Chirp works on most laptops. You will need a programming cable, but those are inexpensive. Chirp has a basic setup which covers standard GMRS freq(s) and should allow you to set up repeaters and use simplex. Quote Link to comment Share on other sites More sharing options...
Flameout Posted December 4, 2023 Report Share Posted December 4, 2023 Have you looked into the older Motorola GR500/GR1225 repeaters? Can usually be found for a few hundred dollars with duplexer so all you need is a GOOD antenna and elevation. I actually have a few of them, with one set up in my area. It works good, but gmrs is kind of dead here. I also have a Retevis RT97 that I tried out for a week or so. I tried selling a complete, tuned (.650) lower power GR1225 locally but no one was even interested Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.