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I discovered the antenna is sensitive to the mounting location and type of mount. I've attached a zip file of some other tests I did with different mounting locations and types of mounts, like magnet - ground radials etc. This was one of the better mounts and location in a home office setting inside a room. https://forums.mygmrs.com/gallery/image/268-ca-2x4sr/ CA-2x4SR Antenna Tests.zip

That's what I mean, it's one thing if they are polite about it and say "hey, we do business on this channel, would you mind moving?", but when they try and throw an authority trip on you like "you need to vacate this frequency NOW, or you'll get arrested for interfering with our official business" that kind of changes things. Like I said, I have all the respect in the world for law enforcement, but these local warrant servers around here with their antics are laughable.

The antenna is screwed into a really short UHF barrel adapter and the other end has a length of RG-8 coax coiled up then reduced to a short run of RG-58. The whole thing is attached to a sawed off clothing display rack I found in the trash. A stainless steel hose clamp is used to hold it on the end of the tube along with 4 brass rods, about 1/16 inch diameter and approximately 19 inches long, bent down at roughly a 45 degree angle for a ground plane.

Over the past few years, I have tried just about every commonly discussed antenna available in the US. I literally have 8 or 10 antennas sitting in my office and garage right now, and 4 more in/on the truck. Anecdotal I know, but the absolute best antenna I have used for 2m/70cm/GMRS is the Diamond NR-7900a. It's rated for 300w/250w and, 3.7/6.4 gain. Real-world, it far out-performs my dedicated MXTA26 GMRS antenna, which is the best dedicated GMRS antenna I have used. Not only is the range the best and able to handle the most power, the SWR on 146.52 is 1:1, on 446 it's 1.3:1, on 462 it's 1.6:1, and on 467 it's 1.5:1. The Diamond NR-770 is a close second. The power ratings are a little lower at 200w/200w, the gain is a little lower at 3.0/5.5, and the SWR is the same everywhere but 462, where it's a little higher... 2:1. It's 1.4:1 on 146, 1.1:1 on 446, and 1.5:1 on 467 (which is where I spend most of my time). The slight sacrifice in performance benefits does yield a smaller, thinner, lighter antenna that is more discrete. However, I still prefer to use the NR-7900.

Well, the install isn't done yet, but I am pretty excited. I figured I would share as I make some progress. I am at about 35%-40% complete after about 8.5-9 hours of labor. I guess over the next few weeks, I'll try to finish up, but it's going to be a lot of labor to finish running wires and to do some custom interior work.

View your post -- three *** (dots) in upper right. Should be an edit option at the bottom of the pop-up menu.

Not that I have found, but I haven’t looked hard.

I'm new to ham and I don't have an SWR meter, but I decided to go ahead and try my Nagoya UT-72G that is tuned for GMRS. I have hit a repeater over 12 miles away on 2 meter with no issue, and the guys on the other end said I sounded loud and clear.

I've did both a few months ago when learning which radios best fit my gmrs needs. I find way more use out of a grms radio that's already set up with the "standard" 22 simplex channels and 8 repeater channels than taking a blank ham radio and setting it up from scratch. I mostly use my radios for simplex comes with my team with occasional repeater use. I'm am often in a situation where the group is mixed gmrs and frs so being able to tell the group, "We are using channel _____." today is just quicker and easier.

That image has a great looking setup! Ill check out the ZIP when I get home.

That fits pretty well with what I remember from when I tested mine (mag mounted, center of roof of single cab compact truck). i generally aim for 1.5 or less, and i want to say 1.3 was about the worst i saw testing with a swr meter, not vna. it does seem to give up a little in exchange for that wide bandwidth though...judging on use, the sbb5 seems to do as well on the fender as the 2x4 did on the roof.

I recommended one of these to a work buddy for GMRS. He mounted it on the driver's side fender of a pickup truck near the roof pillar. The match was reasonably good on the UHF GMRS frequencies. I've attached the scans I did with it mounted on his truck. Being a 5/8 wave antenna it needs a GOOD ground plane to give acceptable SWR across it's operational range. Antenna Scan Results (CA-2x4SR VHF TRUNK LIP MOUNT).pdf Antenna Scan Results (CA-2x4SR UHF TRUNK LIP MOUNT).pdf

I think you are over thinking how to get to your designated simplex. Look into a pair yagi antennas pointed at each other to use just for the hard to reach family. You will also hear the other much better as well. Look at the numbers: Your 25W into an assumed 6db gain omni antenna = 99W EIRP Take the same antenna, boost the power to 100W and you get 398W radiated, but in all directions, and no improved receive from your intended family member. Take your same 25W radio into a 10.2db gain yagi = 261W EIRP, with better ears and less likely to cause interference to anyone else. There will also be more benefit if you don't have 6db gain on your current antenna. This is taking zero line losses into account. Edit, if you get one of the Yagis that has 12.2db gain, you end up with 414W EIRP with your existing 25W radio.

Ham radio operators often get thousands of miles using only a few watts at lower frequencies. Radio is funny. Sometimes more power isn’t the solution, but the smart bet always goes to a good antenna system. I got on a 2 meter simplex net last night and I used my 20 watt mobile instead of my 5 watt handheld. I was able to very reliably talk with the net control who was maybe 16 miles away parked on an overpass, but a very strong signal coming from six miles away and above me on a hill came in very broken blasts, signal strength meter pegging “spurts” that were uncopyable until I turned off the mobile radio and picked up my handheld with its rubber duck antenna. Then I could hear the nearby station very clearly. Sometimes a signal needs attenuation. The best thing is to try different things to see what works.

I have the capability to do it, but I don't have time to mess around and tweak them 20 different ways. I'm kind of curious how you spent $200 already & didn't get the job done. My typical charge to program analog radios for conventional channels is $35 for up to 4 channels. If you want to do something crazy and unconventional - I'll just warn you that I'm probably not your guy. There are issues with the early CDM1550 LS radios not doing MDC, or more than 16 conventional channels - but neither of those items should be an issue for a simple single channel repeater. Biggest issue with the CDM series is setting them up with ignition sense and a predefined home channel, so that they automatically power up and restore to the proper channel configuration if you have a power outage. I'm in Southeastern PA if you want to send me a PM for further info. If you have the capability to read the codeplugs - you can just send me those & we can do it all via email.

I have a friend who retired from the industry a few years ago. Thankfully he got everything sorted for me. Thank you! I appreciate it. I am using the ASTRO 25 Mobile CPS software and a USB cable to program the radios. It's a lot easier than I originally expected. Between the plain english field titles and the help file, I have been able to figure everything out.

Yep, they just contacted me. For some reason the first application did not go thru. They told me to disregard. Thanks everyone [emoji122] Sent from my iPad using Tapatalk

I agree. I would periodically check the data base to see if there are any changes and keep on using your license.

What is the antenna tuned for?

I would add you have a cell phone. It’s okay to use your cell phone. I mean seriously if you want a private conversation radio isn’t it. Sure there’s encrypted radios but that’s not GMRS. Op is looking for a solution where there is no problem. I’m 10-98 ?

Not the same kind of map, but a very comprehensive listing is at repeaterbook.com.