bobthetj03

The swamp cooler on top of my roof would make a great ground plane, and be even higher up, but I would have to run another 25' of coax to reach it. The mag mount I have now is 16' of RG58 coax. If I extend that cable another 25' will I be exceeding a length requirement or start loosing signal strength to bleed off?

It was amazing how much it helped. Using a mag mount and 16 feet of RG58 coax, I mounted a 5db gain antenna on the roof. I can reach 3 repeaters in my area from my front deck. There is a 4th repeater 30 miles away that I cannot reach. Well, last night I was able to reach it, and had a nice conversation with a fellow. My HT was only pushing 2 watts, so it was amazing how much range I was able to gain just from antenna choice and placement.

I'm patiently awaiting the introduction of the MXT-575.

My GM-30 communicates fine on simplex with my 2 cobra HT's, using ctcss tone 67.0. I can also reach my local repeaters. I did do the firmware upgrade as it was doing some weird things with the PL tones.

I can access 2 repeaters from my front deck using my GM-30, but was wondering if I can increase my range if I mounted an external antenna on the roof and hook it up to my HT? There is one repeater I can't quite get to, but can hear conversations from there. As an experiment, I took the small antenna that came with my MXT-275 and set it on a 2'x3' sheet of steel, then set it on the roof. I was able to have a short conversation with a guy 15 miles away via a local repeater, but not sure if I gained anything or not.

The Radioddity GM-30's can hand split tones and are inexpensive. Retevis has a cheap one too.

Are there any other radios out there that have all the controls on the mic? That particular format is desirable to me for mounting in my Jeep.

Yes, it was resolved with a firmware update. It's all good now.

I'm assuming I have to download software to program the DIY frequencies?

I did the firmware update, and I now have an additional 24 DIY channels. Not sure what to do with those?

I had something weird happen with my GM-30. Went on a road trip over the weekend and was passing close to a repeater I can't reach at home. I put in the proper frequency for the repeater and the ctc tones (136.5), turn off the DTC tones, but when I did, it would clear my ctc tones inputed and turn the ctc tones off. When I go back and turn the ctc tones back on and re-enter the tones it turns the dtc tones on as well and selects D365N, so now the dtc tone is on and the ctc tone is on at the same time. If I go to turn the dtc tone off it turns my ctc tones off too, but it'll only do it at that specific tone frequency of 136.5. I enter any other tone frequency and it operates normally as it should. Weird.

Repeaters that use split tones can be a challenge for the mxt-275. Split tones are when a repeater uses a different tx tone than the rx tone. Many repeaters in my area will use the same input/output tones, but there are some that use split tones. Sadly, you can't program for split tones with the 275. You can, however, turn the squelch off (turn on monitor button). You have to listen to static, but you'll hear the rx transmission. I turn both speakers on and key the mike so that just the power unit's speaker is on so the static isn't so annoying. Word has it the soon to be available MXT-575 will fix this.

This article helped me. https://www.k0tfu.org/reference/frs-gmrs-privacy-codes-demystified.html This HT is a good bang for the buck radio. https://www.radioddity.com/products/radioddity-gm-30

I'm at 650mm currently.

It's mounted above the driver side tail light via a bracket that is attached to the tub with the tail light housing bolts. I Took a reading prior to trimming and got the 2.20. Trimmed it 3 times in very small amounts to get 1.94. I'm afraid of trimming off too much at this point. I can get 1.01 with the small mag mount antenna setting on the same spot.

I tested SWR and got a horrible 2.2. Trimmed a tiny bit and can only get it down to 1.94. For testing purposes, I removed the 6db whip and put the magnet one that came with the MXT-275 and get almost perfect at 1.01. I checked my cable for any sharp bends or pinches and can't seem to find anything out of the ordinary for routing a cable in a jeep. With the cable and antenna being the only change I have to assume there is something wrong with either the 6db antenna, or the coax?

So, the tail light mount bracket that is bolted to the jeep tub isn't enough of a ground plane for that antenna?

What difference would the longer 6 meter cable for the 3/4" hard mount make in this equation?

Instead of starting a new thread, I'll add this issue I'm having with this antenna. It has happened twice now, and it's when I'm on the freeway and it's windy or inclement weather. The antenna starts whipping violently, hitting my hard top. I have to come to a complete stop, and that is not fun on the interstate. It's like the spring is too weak. This used to happen with my 3' Firestick, but I cured that by installing a stiffer spring. Anyone running this antenna experience this issue?

Doing a bit more research, I found these are VHF radios. They are operating in the 150ish range, I think. We've installed a few of these units in our local road crew trucks, and I have just wired one up to use as a base unit for when we need communications with field personnel. https://www.ebay.com/itm/265087086006?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=265087086006&targetid=882300791467&device=c&mktype=pla&googleloc=9032344&poi=&campaignid=1669934603&mkgroupid=65058347419&rlsatarget=pla-882300791467&abcId=1123856&merchantid=8457704&gclid=Cj0KCQjwi7yCBhDJARIsAMWFScOqZJx25jwEpm9OGxyVCy-BW0O4c04vUJL8-KCC2tTA-nHPseKIrr4aAqHaEALw_wcB There are a few maintained repeaters that are used in our county for these radios apparently. I was mostly just curious of the technology behind it, as it seems similar to GMRS, other than it's VHF vs UHF.

What type of radio systems do most local county government and law enforcement use for their mobile radios? I work in local government for fleet management and see a lot of Kenwood units in the cars, plus our local road dept. has them as well in their work trucks. They use repeaters and was curious if they use a form of GMRS or a certain set of frequencies to work off.

2003 TJ. Replaced my old school Cobra 66LTD and 3' Firestick with a MXT-275 and 6db antenna mounted above the left tail light. I can't shrink the pic I wanted to post small enough, sorry.

I'd be embarrassed to tell how much I've spent on my POS!

Guilty! TJ owner here. I'm just trying to justify spending $45 on a SWR meter at this juncture.

Midland claims the antenna is pre-tuned for Midland radios, but I'm wondering if there is room for improvement, as Midland has a tendency to dumb down the GMRS radios for us newbs. Is it worth buying a SWR meter to find out?