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Send them that bug report.

It's a Smith Chart SWR Circle. It's a circle that is drawn centered at the origin frequency, passing through the plotted impedance point. This circle represents a constant SWR through the range. The value where the SWR circle intersects the positive real axis (right side) of the chart indicates the SWR. The closer the red dot is to one of the lines radiating from the right side, the closer to 1:1 the SWR is on that frequency. I tried the TinyVNA and it did not work. It was way off... very inaccurate. A friend of mine (who is a retired RF engineer) uses a SAA-2N VNA when he is in the field. He has great results with it, which is why I went with that specific VNA. It's "good enough" that I would not encourage people who are doing this as a mild hobby to buy a commercial Signal Analyzer. If professionals are using it, the SAA-2N VNA is good enough for me. I have not compared mine to a commercial grade SA, but I have tuned 5 duplexers (UHF and Commercial VHF) with the SAA-2N VNA since I bought it and have had amazing results. With a 2m repeater only having a 600KHz offset, accuracy is extremely critical. My 2m repeater is covering over 8 miles with 5w handheld radios and well over 25 miles with 50w mobiles, and the antenna is only 100' above the ground, 200 feet above average terrain. Those numbers are both further than the theoretical/calculated RF LOS. So, I personally have confidence in the SAA-2N VNA.

Without knowing what frequencies are being used locally there I think that would be a dumb idea. There are warnings all the time against taking FRS, same frequencies as GMRS, radios on foreign vacations since the frequencies could be used by local fire, police etc. services.

I've held off spending money on one of the tiny VNA's since I'm not really convinced they have the dynamic range claimed. I would like to see some verification of the spec's testing against a know high quality lab bench VNA. For tuning these cavity filters you really need the high dynamic range to be sure you have all of the cavities aliened.

You're as bad as me for staying up late. LOL Ya, I saw how they painted the screws. Shot them from one side to help lock them in I suspect. Didn't think about how that might impact re-tuning though. Thanks for the tour. Do you know how to read the circular graph? The curly cue lines are intriguing, really curious how they are read.

I think I've finally sourced the issue. I did another firmware update, and completed another factory reset. This fixed the overall issue (so i thought). As I started piecing settings one by one, to try and source any further issues, i found that when you turn on the weather alert the previous issue happens. Once it is off, the radio works as it should.

To answer question about tools used and how to adjust a duplexer, here is a quick overview. Tools I used: Windows PC SAA-2N VNA VNA View software Box Wrench Screw Driver Brass Brush To tune the duplexer, you have to follow a couple of steps. Calibrate the VNA for the frequency you are testing (via the PC or on the VNA, depending on if you are using the PC or not) I typically set the center frequency to the frequency I am tuning for, with a 10MHz spread. From there, we are going to tune either the low side or high side, separately. For this example, we can start on the low side. Connect the S11 cable to the "antenna" port. Connect the S21 cable to the "LOW" port. Put a dummy load on the "High" port. Refer to Image 1. Set the Trace 1 format to S21 Thru. With a mobile UHF cavity duplexer, you can disable the other traces, but if you want to track your SWR at the same time, set Trace 2 format to S11 SWR, and then disable the remaining traces. Adjust your scaling so you can see at least -110dB Adjust each adjustment screw to create the deepest notch possible, to the transmit frequency. In this example, 467.600MHz. only adjust one tuning screw at a time, loosen the jam nut with the box wrench, just enough to allow the tuning screw to move, and while making adjustments, hold the jam nut with the wrench. Typically, once you set the screw to the proper depth, it can be a bit tricky to set the jam nut without turning the screw a bit at the same time. A trick I learned is that I put the screw just a few degrees off, counter clockwise, so as I tighten the jam nut, it snugs the tuning screw into the correct location. See Image 2 and Image 3 From there, switch the S11 cable to High, and the dummy load to the Low side. Repeat the tuning steps for the high side, but tuning the notch to the receive frequency. In this example, 462.600MHz. This guy has a great video on using a VNA to adjust a duplexer. I have no idea who he is, but it it's good content. The only thing I would add is, he stated he is using 200 sweep points. I would use the highest sweep setting you can that provides a good enough resolution of the frequency spread you are tuning. On the VNA itself, I use 401 points, but on the PC, I use 1024 points. https://www.youtube.com/watch?v=TbEK4v_3Xuo With this duplexer, specifically, the tuning screws are brass. Either the manufacturer or B-Tech spray painted the tuning slugs. I had to spend a bit of time cleaning the paint off the screw threads and heads with a brass cleaning brush to make it so the duplexer could be tuned. If you have a situation like this and want to repaint the screws for cosmetic reasons, be sure to use non-metallic paint, such as Krylon Fusion for Plastic. It must be non-metallic, polyurethane free, and lead free. I am including a few extra pictures displaying the results. Image 1 Image 2 Image 3

I guess the receiver sensitivity is what it is, but if you are able to receive better with the new duplexer that's real world sensitivity not theoretical receiver sensitivity. I get exactly what you are saying. And I'm pretty sure you know what I mean too. If I could hit the repeater at 5 miles and not 6. Then install the new duplexer and can hit the repeater at 7 miles but not 8. I would consider that an increase of sensitivity. But in reality it's the duplexer allowing the receive signal to still be heard while the repeater is re-transmitting and not causing desense.

More waterproof.

Yah, sounds like you bricked it.

That's what I meant

That's a good question, but not the way receivers get rated. The sensitivity is the 'receiver' sensitivity. A couple points about how the duplexer work and why the receive sensitivity isn't impacted. The duplexer filters out the receive frequency on the transmit side, and the transmit frequency on the receive side. There is no direct impact to the signal due to tuning. The only real 'reduction' would be the overall reduction in signal from insertion loss. However, you may see a difference/improvement due to the filtering for another reason. The cavity filters have a bit of a floating echo effect, with the dB of suppression wildly varying. Your duplexer, for example, floats between -85dB and -110dB per cavity pair. With a varying isolation of -170dB to -220dB. Prior to tuning, the duplexer isolation floated between about -45dB and -70dB. This can impact how much desense the receiver experiences, giving you the impression that receive sensitivity improved. To summarize, while the receive sensitivity doesn't improve with improved duplexer tuning, the improved filtering removing more of the transmitter signal and reducing desense, will allow the appearance of improved sensitivity.

You may want to do spend a little time watching some videos and researching on this site before making another purchase. Learn how to program repeaters and what limits you might be on the radios.

I guess another interesting note. I just turned both of the radios on again, I was able to get the HA1G to pick up one single transmission from the GM-30, immediately after depressing the PTT on the GM30 the green indicator light on the HA1G turns on constant and I can no longer receive a transmission until the radio turns off and back on again. Update: I can get the HA1G to rx from the GM30 all the time if I have it in scan mode, but once scan is off, then we revert to the whole no RX problem.

ASL (All Star Link) is right there too. ANd it's the ASL code that myGMRS was using. It's what Freedom Nation is still using. And the DVSwitch phone app will connect to a node directly with no server in between if you know what you are doing. I personally don't bother with any of that and just use MotoBridge since I have direct wireline connection to all my repeaters with it. In addition I have numerous other radios that I have full control of IE, zone and channel selection, front panel button access and control. All the good stuff. But, ASL, or even the old image we were using for myGMRS can be modified to be connected to with the DVSwitch app. My guess is it was never talked about by the admins because it would have been one more thing to provide assistance and support on if they were to have mentioned it would work. I have seen it work, I have made it work. I am NOT going to help anyone else with it. They can figure it out on their own just like I did or give up in disgust.

I did update the firmware on the HA1G. Maybe that did something?

I'm looking into the Wouxun KG-805G but if I wanted to look into the 905G model what do you mean by it has a bit better IP rating? and if I was to lean more on the KG-805G what program cable would I get I cant seem to find one for just that model on amazon.

I noticed that I am going to return it. I am looking at what few people have said though to look into the Wouxun KG-935G heard it is GMRS and a okay radio to start with.

You bought the wrong radio. Because it is a H.A.M.s radio, it likely will not be able to transmit on GMRS frequencies. IF it does transmit on GMRS, or IF you can get it unlocked, it is going to take multiple semi-complicated steps to program a repeater.. Good luck. ..you really did buy the wrong radio... UNLESS you bought the GMRS version, in which case if you did, you dont need to enter any frequenices - just pick the repeater channel, enter the TX tone, and talk..

so I ended up getting a Baofeng uv-5r just for something to practice on while I do more research on a decent one. so I got one without a program cable sadly. I am trying to manually set up my radio so I can transmit on it. but no idea how to do so I went on map and found a repeater I am close to. went and put in the frequency but that all I really know how unless I'm doing something wrong. please any help

Do a reset and you should be good after reprogramming.

Even though they don't call it GMRS in Iran this is the perfect situation to offer cheap disposable GMRS radios to the rescue workers to facilitate efficient communications.

You are correct it is the two lined version.

That may be the original 2-line display model. The ones I was referring to are the new full-color screen models.

Joined May 22, so over a year