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That sounds like the radio is scanning, and it gives you 4-5 seconds to respond before scanning resumes. So on the 935G you would enable scanning and set the scan mode to "SE" in Menu option 15) . You can optionally select a priority channel as WRPD494 mentioned. With Menu options 18 and 19.

True, they would work far much less sucky on the moon or way out in the boondocks. In fact, Midland backs up their 32 mile claim for their GMRS radios by testing them line of sight from a huge hill way out in some wide open rural area. The lawyers are happy, but folks who now have those radios, question the claim when they barely get a half mile in a suburban area. I have some ICOM IC4008A FRS radios that are superhet, but very basic design with little preselector filtering, just a simple coil. Better than an SOC design. They work very well out in the National Parks. But around town, not so much. I keep them because they are easy to use and the AA batteries last days when camping. My wife and son carry them because they are small. A radio is a tool like anything else. A battery operated drill from China sold at Harbor Freight might get by for the casual home user. But I have a Japanese Makita drill I purchased in 1980 for $300 in 1980 dollars , that has outlasted all of the cheap drills I bought in the meantime. For $35 You are not getting much of a drill. Same for cheap radios. Sent from my SM-T350 using Tapatalk

As to legal power, I understand the rules to mean 50 watts (MAX) at the antenna port of the transmitter, as opposed to ERP (Effective Radiated Power/what the radiated signal is). That said... No matter what you do, there is going to be loss between the TX/RX and the antenna. I don't know about 4dB 'in the box' but... The average (decent) duplexer has (or should have) 1.5dB or less insertion loss (each respective side, TX and RX), so there goes a 'watts' or so. If you really like your TX, a circulator in the TX side is nice, but rarely done and, would likely add about, or just under, another dB of loss, so there goes another watt or so. It's fair to say that even if your TX is putting out 50W from the PA, by the time you connect to the antenna system, that 50W is going to be 30-40W (if you're lucky). That is, again, typical. I'd add that the losses go both directions so your RX sensitivity just got a little worse as well (but not earth shattering). This is why antenna system design is a make or break scenario. The gain of the antenna ideally makes up for some of the line and perhaps even the duplexer loss and, if it has some gain, maybe focuses what energy it does radiate and receives where you want it. As for tweaking the PA for more power, it doesn't really help, because once again, there is loss on the receiver side too, so upping the power is only going to make your repeater talk where it can't hear the people trying to talk into it. As noted by another poster, it also risks cooking the PA itself and/or the power supply feeding it. Now I know in the 'hobby' it isn't practical, but the ultimate goal of a repeater design/system is to be able to have the talk-in balanced with the talk-out for a given user radio and antenna combination. You really can't do that thinking in watts, which is why the practice (for people who do all of the above) is to work in dB (decibels). Why? Because losses and gains can be added up and subtracted to find out what you actually are dealing with. Watts equates to a level of dB as does cable and other losses, antenna gain (or loss) and, the sensitivity of the receiver. Indeed, for all the hoopla about tweaking a PA and squeaking out a couple more watts, if you look at power output in dB as apposed to watts, you find even doubling the watts isn't really a whole lot of gain in the bigger picture. FWIW...

I think I could still write a book on this subject. Or those that do this with every radio or related device they get their hands on. I still recall co-workers that tweaked "golden screwdriver" style their Maxtracs for as much power output as possible, then it was the Spectra's then Waris CDM series, and on and on, while they burned up radios. Some service shops have done this to create more paying work from their customers, though they will never admit to doing so. Most recently, I had this happen on the repair of several MTR2000 repeaters with failed power supplies. Repair/replace the power supply and find out they had tweaked output wattage to try to get max ouput power, which then bore down the power supply, shortening its life. Excellent point there.

Sorry - I thought you wanted to be able to PTT to talk back? In that case, SE is better? Either way, use what works for you and enjoy the radio - The 935G is my favorite GMRS HT.

My read is that TPO is where the transmitting equipment meets the feed line. If transmitting equipment includes harmonic filter, circulator and a duplexer,, so be it, no problem. As long as the TPO is 50 watts. The Motorola MSF5000 station integrated all of those optional components making a 100 watt station deliver 75 at the connector on the cabinet. This confused technicians who would see that the station was spec d at 100 watts without those internal options, and so they would turn the power up to squeeze 100 watts from the cabinet and that would make the PA run much harder. Sent from my SM-T350 using Tapatalk

Hey folks, I am leaving for vacation in a couple of hours and don't have time for a proper test... but I wanted to let you all know that I got the radio back from Midland and I can't be happier. With a quick bench test using low pressure alligator clip test wires for the power supply, I am now getting 48w of output power on both the 462MHz and 467MHz frequencies! I'm sure with a proper power cable, it will be perfect. Once I get home and have a chance to do some proper testing for output power and 12dB SINAD receiver sensitivity test, I'll share the results.

The thread here sparked an internal debate in my head. 47 CFR 95.1767(a)(1) states "The transmitter output power of mobile, repeater and base stations must not exceed 50 Watts." In the other thread, that version of the Bridgecom hardware provides 4dB of insertion loss before you even connect the antenna feed line, loosing 60% of your power right off the bat. In otherwords, before you eve get to feed line loss if you have 50W out of the repeater, you are down to 19W. Again, this further points to the importance of proper feed line choice and a great antenna (why skimp if you are already dropping $4k+ on a combiner). Even with hardline, you could only see 6.8W/10.7W/12.7W to the antenna with 1/2"/7/8"/1.25" on a halfway decent tower site (300'). Potentially, a manufacturer could potentially provide a 8U complete box with a single coaxial connector that puts out exactly 50W at that connector, but has all the combiner, transmitter & receiver in the single box, and if that enclosure package was tested and achieved the part 97 certification, would be acceptable for use for GMRS. The obvious would be that the transmitter would output higher than 50W to overcome the losses internal to the box, but since its "one piece" could potentially pass the transmitter based on that. This is slightly different from most repeaters, since the duplexer may have a spot in the case, the jumpers are exterior, and the rating is for the raw transmitter output before the duplexer. Now I have my opinion/interpretation, but I'd like to hear from others. Where is that power limit taken from and why? This is not to say that anyone would know/notice/care if you ran an amplifier to make exactly 50W come out of the duplexer or combiner. Not saying you should, but its not impossible, not that there are part 95 certified amplifiers available that could handle the duty cycle needed.

I wanted to throw out of post of good commercial antenna's that work great for GMRS as well as other LMR applications. Every antenna listed I have used for home and on towers and have had little if any issues with. Laird - Laird FG Series is a great antenna for home use and limited tower site use. Great for a home repeater when a tower is not available. Mostly omni. FG4500 - Unity Gain Fiberglass Antenna N Female 100W 450-470mhz - Cost around $125 FG4603 - 3db Gain Fiberglass Antenna N female 100W 460-470 - Cost around $140 FG4605 - 7db Gain Fiberglass Antenna N Female 100W 460-470 - Cost around $200 You can get more specifications from Laird here - FG Series Antennas I get most of my hobby antennas from The Antenna Farm The next step up is the dipole antenna and is normally the base antenna I'll install on a tower site. The DB aka CommScope Dipole is a rock solid performer and works well in long term use. I have used these in the ADK park on mountains caked in ice to towers in SE VA and other than physical damage never replaced one. DB404 - 3.8db Gain Dipole Antenna - N Male 250W 450-470mhz - Cost around $500 DB408 - 6.6db Gain Dipole Antenna - N Make 250W 450-470mhz - Cost around $1000 You can get more specifications from CommScope here - CommScope I use various vendors for CommScope gear. Antenna Farm linked above does carry the DB404 as does MyGMRS. MyGMRS would be my first choice as it helps support the site and forum. His price is comparable to what I get it for from Tessco. When looking at an antenna also remember the cable to the antenna to be almost as important as the antenna. Putting a DB408 on a tower isn't going to perform as expected when you run LMR400 to it. It should be LDF. In reality if its on a tower it should be LDF anyway. Some real case uses of antenna''s above for me. My 38' Motorhome has a GMRS repeater. for years I ran the GR1225 and since have switch to the RT97. I run the FG4500 on my ladder and it works perfect for camgrounds/race track use. I have used the FG4605 for years on a repeater at my fathers house. He had a small mast system and it was a great match. I ran 1/2 LDF up the mast and to the antenna. The DB404 is my favorite. Thats what I have at home on a 1 1/4" Pipe on my roof. I run the DB408 at the tower with 7/8" LDF down to the combiner/duplexers. Just wanted to get some info out there on better antennas and options. TRAM, Comet, Ed Fong are all that. They are hobby antenna's and may not meet expectations. Some even cost the same.

From Post here - HERE @Flameout said - "The cablelowering it and all of a sudden I could pick up the repeater. I just had lots of noise, especially compared to the mag mount Nagoya about 3' off the ground. I really wouldn't mind buying another antenna if I knew it would work. Too bad there isn't a store that rents them is 50' of ABR Industries RG 8/U and the SWR is great (but then again, it is also great using a dummy load) I had the antenna up about 20' but experimenting one day, I was" @WROZ250 gave you some good info. For a base radio I'd use the best you can find. You said you are using 50'. Do you really need that much cable ? I would use the least amount as possible. I'll be honest I would not even entertain 50' of LMR myself but know not everyone can afford LDF cable. I would say if you can get down to 25' of cable you may find a much better experience. I will also suggest watching ebay for LDF. I have seen 50' chunks for around $100. You need to search and it may take some time but LDF is online and can be had reasonable.

I did a similar design in NY. All 3 repeaters were the same output, however all three used a different input PL. I called it a poor mans voting system. There are similar systems in public safety. Actually our SAR system started the same. Same TX/RX all over the area with different input PL tones. All TX was the same PL. Really need more info as said.

Yes, USB cables with an FTDI chip are the best way to go!

Likely you are referring to priority scan - radio will scan, or while another channel will continue to "monitor" your priority (user selectable freq or channel) selection. Some radios call it dual watch, and depending of whether your kit has true dual VFOs or does some fancy fast switching in the background it generally works well. I believe the 935g has Priority Scan along will all the other advanced bells and whistles.

Can anyone explain why that program draws a straight line from Wisconsin to France? I guess it must be for Flathearthers.... G.

Thats not the real-world that I live in, so i'm glad to see that for everyone like me not in an RF-heavy urban environment, the radios dont "suck" .. Because at first, based on your statement, us non-techy people might have misunderstood you to be saying "they suck", which it seems is not the always case, so thanks for clarifying.

Most of the cost of a radio goes into receiver design. All manufacturers must meet minimum FCC specs for the transmitter, so that cost is fixed. Cheap radios will have simple receivers. SOC, System on a chip receivers have a minimalistic design controlled by software commands. The main thing lacking in these designs is RF preselection . The other problem appears to be the lack of an effective FM limiter circuit. While these radios might seem very sensitive in a controlled environment, they really suck in the real world. Commercial grade radios and public safety grade radios are tested to EIA 603D. If a radio is decent, it will have published EIA 603D performance specifications. Only a minority of the radios available for GMRS have such published specs. Sent from my SM-T350 using Tapatalk

Tram Browning BR-6140, $51 on amazon and elsewhere. Unity gain, 2 ft tall, N connector, comes with mounting hardware.

I think so, the Harvest brand folded dipole goes for 70 bucks on eBay. The 2 bay dipole goes for 140 bucks on eBay. I think folded dipoles are great b/c they have super wide bandwidth and they are very resilient to noise. single dipole link: https://www.ebay.com/itm/133810193897?epid=1941709490&hash=item1f27b585e9:g:Y5EAAOSwLCdgUyaI 2-bay link: https://www.ebay.com/itm/133927735178?epid=1941709490&hash=item1f2eb70f8a:g:yowAAOSwIytgUyhQ

I would assume an EdFong antenna means some sort of base radio. Superheterodyne can be poorly designed too, just be aware of that. My recommendation for radio goes for the Vertex Standard VX-4207, which will not intermod, nor desense, and its part 95. @wayovertherehas experience using that radio. For antenna I would go with this: https://www.ebay.com/itm/133810193897?epid=1941709490&hash=item1f27b585e9:g:Y5EAAOSwLCdgUyaI, which you can later upgrade to a 2-bay or 4-bay configuration for increased gain. G.

Guys lets get back to the Midland MTX500 stuff. There is a section in the forums for arguing called Amateur Radio or Miscellaneous Topics

Assuming the meter is working correctly, and installed in circuit correctly then there is a problem with your antenna system (feed-line, adapters and antenna). Now begins the process of elimination. You may wish to try your measurements again using the shortest possible cable length and different adapters as you have them available to see if results change. I am not a fan of cut-by-chart trimming of antennas. When an antenna is known to be long for its intended purpose, I prefer to trim a little and measure, then repeat as necessary so as to sneak up on the target value. Doing so helps you know where you are getting close (because SWR gets better with each snip) but also when you have gone too far (because SWR starts to rise). Be aware that at high frequencies, minute length changes can cause big changes. It is possible that you may already snipped it too much, but also that you have not snipped it enough. Further, If you are testing using repeater input frequencies (467 MHz range) and the antenna is actually tuned for 462 MHz range, then the 467 numbers will appear higher than the 462 numbers. Snipping of course should only be done on a basic antenna, or one that is, by design, intended for sniping and/or you have advanced knowledge antenna designs. I don’t own your specific antenna, so I cannot cannot from experience comment if it is designed for cutting or not. For what is is worth, there no such thing as an SWR of less than 1. The first number is always 1 or greater, and the second number is always 1. Collectively they would appear as follows: 1.5:1, 1:1, 1.15:1, 4.7:1, etc. So .8:1, 0.5:1, 1.25:2 are all examples of invalid SWR values. Hope there is a little nugget of assistance in there. Michael WRHS965 KE8PLM