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Now to start planning an attic antenna!

Got two new Wouxun KG-S88G handhelds. Super het receivers. Reception seems to depend heavily on the exact position of the radio. If I place it HERE then it's great, full-scale reception of the repeater. If I move it a few inches over to THERE, reception can go to near 0, sometimes not even breaking the squelch (set at 1, where 0 is open). If I move it around a foot or so further, it may suddenly become great again. If it stays put where the reception is great, it stays great. Both radios behave the same, either with the stock antennas or the 15" Nagoya GMRS-tuned antennas. Two radios, four antennas, all do this. This testing is being done on the 2nd story of a house with aluminum siding. Faraday cage with windows, possibly bouncing signals all over the place inside. Meanwhile, the cheap FRS Midlands receive almost anywhere, and usually better than the Wouxuns. When one of the new units are placed in a good spot then they best the FRS, but most places the FRS best the superhets. Handheld transmission does make it into the local-ish repeater and I got a successful radio check, although that was down the street while sitting in the Jeep with fibreglass top, not from inside the house. In testing between both new radios from across the subdivision, the new radio did hear better than the FRS. When I went further away to where reception was lost and switched to the mobile unit at 15W, inside the house the FRS received the mobile better than the new Wouxun. But my wife admitted that the new unit may not have been exactly upright, and the 15" whip was installed at the time. Angle of antenna? Perhaps keep the stock antennas for a more wide-angle dispersion at the expense of range? So do I have two bad radios, or is this a characteristic of superhet receivers, or perhaps are the FRS designed for hyper-sensitivity at the expense of selectivity, for example?

I heard similar while passing through some rural Virginia mountains. Just below the interstate was a small town in a valley, and the radio started picking up neighbors just chatting and saying hi to each other. As you say, a great way to stay in touch during the dark days of winter. The linked net repeaters are very big on call signs and such, which doesn't really get in the way. Sounds like a certain number of regional friends hanging out all the time. The net might get 100+ check-ins. The unlinked local repeaters are local friends, maybe 10 check-ins when they do their own net. Same people all the time, but a lot of newcomers as well. At least in the midwest, GMRS seems like friendly-ish CB.

An adhesive metal antenna mounting disc: TAF DISC3.5 It may be required to cut off a bit from one side because the JL/JT hood has only so much flat surface near the edge. Also: MicroMobile MXTA38 Adhesive-backed Metallic Mount

Regarding routing the cable for a JL/JT: Jeep Antenna Mount

You can buy an adhesive metal disc and stick it on the aluminum hood. I placed it near the back of the hood, but several inches away from the back edge to provide a bit of ground plane to the back. And several inches away from the side edge as well. I also ran a grounded wire in the slot at the edge of the plastic cowl, forming a ground radial in the backwards direction. All of this keeps it away from tree branches fairly well, and if it's a short antenna then it isn't too much in the way of the field of vision. Mine is a Midland MTX275, which came with a little 1/4 wave antenna with 20 feet of thin RG-174 coax. That coax eats a lot of signal. If you have this, either get a better antenna or chop the coax down to size and install a connector. Even better, what I did, chop the coax to one foot to get under the hood, then use connectors and an adapter to run RG-58 the rest of the way to the radio. For the JL/JT, there is another post here somewhere showing how to route the cable under the cowl and through the driver's door leading edge. It works great.

May have antenna tuning issues if the freqs are far from the current ones. Otherwise, a sensible idea if much of nearby ham freqs are unused. Equipment would be just as locked down as current GMRS.

2017 or so? I have some which are older which I suppose would be .5W.

For back country, I've used a Garmin Inreach several times just to send and receive text message updates. There are also some volunteer 4x4 offroad recovery assistance groups which can send help getting unstuck via text message without relying on emergency providers. For the FRS radios, be sure you have some manufactured fairly recently, where they upped the power output to 2W. If you have older ones they may be .5W.

Their advertising is getting a lot of new people into GMRS. Maybe a good thing? And that advertising is paid for by charging for their products. Anyhow, they're all over the offroad and outdoors crowd so expect to see more and more people coming in.

I've mentioned this elsewhere but will repeat it here for the original poster: The 275 comes with a nice little mag mount antenna with an adhesive disc which can stick on aluminum hoods, but it also has very thin coax which soaks up a lot of signal, essentially turning a 15W transmitter into a 6W transmitter. It also soaks up reception. So get another antenna with better coax, preferably only as long as necessary. In my case I changed the original antenna's 20 feet of RG174 into 6 foot of RG58 plus one foot of RG174 where it goes around the edge of the hood. But that required cutting and adding a connector to the original cable, plus ordering more cable. So just get a mag or lip mount NMO connector and a quarter wave antenna. Some allow you to select coax length on order. And you can still order an adhesive disc for the mag mount if you wish. In fact I'd recommend it to save the paint job.

Interesting stuff. Someone did tell me though that my 275 with upgrade sounds as good as any Midland they've ever heard. I may end up with a 575 some day though. Controls on the handset are great for these Jeeps.

Well for the latest revision they made some changes to supply USB-C. I don't know if they changed anything else as well.

Recent versions of the MXT-275 with a USB-C port can have wide band on the repeater channels. The first run with USB-C, which may still be on the shelf at retail outlets, has to be sent back in for reprogramming. (Quick turnaround!) Later USB-C models come from the factory with wide band already programmed. The non-repeater channels have narrow band. For example, ch15 is narrow, but ch15 repeater is wide. No user control over wide/narrow by channel. After reprogramming and antenna cable mods, my 275 was reported to be as good as they've ever heard a Midland. (Which may not mean a whole lot, but it's something.)

Well the 2 bars of noise (repeater channels only?!?!) disappear when the dashboard display turns off. Not when the engine turns off, but rather when the display blanks a minute later. And the radio is mounted just below the steering wheel. The only other radios I have are simple FRS w/o signal meters. Anyhow, it's not a big problem, and the repeater signal levels are stronger with 14' of RG174 removed. And they heard me when I transmitted. These 2 bars of noise probably used to exist before I shortened the cable, it's just that it was attenuated by the longer cable at the time to something closer to 0 bars. I'll go ahead and order some RG58 and connectors and turn it into 1' RG174 plus 5' RG58. Better shielding near the dashboard, and more signal overall. And I'll order some ferrite beads. And maybe ground that hood too.

The mystery deepens! When the dashboard display turns on, whether or not the engine is running, I see two bars of signal strength on the repeater channels but not the simplex channels. Not enough to break the squelch or stop the scan. Somehow the repeater channels are being treated differently than the simplex. And there is still some engine RPM related noise on some of the frequencies. Now this is all compared to before two recent changes: 20 feet of RG174, 14 of which were in a coil, have been reduced to 6 feet of RG174. And it went in for wideband reprogramming, and came back with a test report. Perhaps they adjusted analog gain somewhere. Anyhow, there are a lot of digital signals running around inside modern vehicles, and the antenna cable routing or shield quality could be issues. I can improve this by changing to 5 feet of RG58 plus one foot of RG174 and a connector going to the hood. I can also order some ferrite beads for the antenna, microphone, and power cables.

Yea, while scanning on the 275, when you hear a repeater it may be the repeater channel or the simplex channel. You have to make sure you move to the repeater channel before replying.

Thanks all. And another curiosity: why would Midland have the scan function scan through all the simplex channels then all the repeater channels? I.e. it scans both 15 and 15 repeater. Why not skip the simplex version of the repeater channels, if you have the repeater channels turned on? Anyhow, things appear to be working well, and it's a nice radio which tucks away under the dash, and Midland did do a good job returning the radio quickly. It even came back with a test report proving full power output and such.

Got my Midland MXT275 back from them (very quickly!) with new programming for wide band for the repeater channels. I noticed that when listening to a repeater, and I compare the received signal strength between the simplex channel and the repeater channel, the repeater channel seems to have better reception and it shows as another bar or so in signal strength. So, on a Midland 275, does channel 15, say, use narrow band reception and "15 repeater" use wide band reception, and would this account for the difference in signal strength? I didn't notice a difference before the wide band programming update. And if I have an FRS radio tuned to 15, and it hears a repeater, why isn't the audio overdriven? I somewhere read an anecdote about a group where almost everyone had narrow band FRS radios but one person had GMRS wide band and his audio was horrible to the rest of them. Perhaps repeaters receive wide band but transmit narrow?

The radio arrived back today, and I reinstalled with the newly shortened antenna cable. The noise is now gone. 14 feet of RG174 in a coil was really picking up something. It's a JT, and those hinge bolts are recessed pretty far. The threads are really back in there deep. I may be able to find a metric standoff which would work. But since the noise is gone I guess it isn't necessary. The mag mount steel plate is not really sticky tape, but rather a thin layer of only adhesive. No backing. My concern with lip mounts is that they seem to require the screws pierce the paint to metal. Unless thoroughly protected these will cause corrosion, especially with the aluminum and steel in contact.

Center conductor. Eg. RG58 A/U vs RG58 U. I find mag mount antennas for each. I've had solid wires break eventually for automotive, so I'm surprised that the antenna vendors are using small solid conductors for their antennas.

I noticed that most of the commercial-grade antennas for sale seem to use solid core cable. For mobile I'd assume that stranded would be better. So in the long run, for mobile use, how well is this stuff holding up?

It's a new Jeep with aluminum hood and fiberglass roof, thus the location. There are many wires in there which could be causing engine RPM dependent noise. I want to RF ground "bond" the hood to shunt these signals to ground. While it could be said that the hood hinges and latches ground the hood, I've seen some recommend the braided ground cable for the hood, trunk (where present), exhaust, etc, especially each horizontal surface. The little stock antenna has an advantage in that you can open the hood and tuck the antenna away under the cowl for storage in case you want to hide radio stuff. And it doesn't attract much attention when deployed. I did cut back the 20 feet of thin RG174 down to six feet and added a connector. According to Coax Calculator this will change my radio from an effective 6 watt unit into an effective 11 watt unit. If it used RG58 it's be closer to 13W. Some day I may cut it down to one foot and use connectors to RG58 for the other five feet. In the end I'll just experiment and see what happens. The radio is currently at Midland for wide band reprogramming.

Midland MXT275. I get mild alternator noise in the mobile radio. The radio's power leads are wrapped several times through a ferrite loop. The antenna is a mag mount on the aluminum hood via an adhesive metal disc. No ferrite beads on the microphone cable or antenna cable, so far. I have two foot braided grounding strap which I'd like to use to ground the hood better. Drilling and bolting into the aluminum hood can lead to corrosion due to dissimilar metals. The hood hinge bolts are recessed pretty deep so it's hard to get an additional fastener onto them.. I was wondering about the idea of using capacitor coupling for the grounding strap, similar to the mag mount antenna. The strap could be bolted to a painted metal plate, and the plate could be slid under the hood insulation where it is held by a clip, holding the disk against the underside of the metal of the hood. Perhaps I would use one of the self adhesive discs which are sold for mag mounts. Is this a reasonable approach, or should I get the beads for the antenna and microphone cables, or all of the above?

A self-adhesive metal disc which sticks to the hood and allows a magnet mount. A nice advantage is that the mag mount is not scraping the paint job, thus saving the aluminum underneath. TAF DISC3.5 There is a larger size as well. Midland has a few mag mounts available with similar metal discs.