Fixing the Explorer QRZ-1/CHIRP 'Tone Squelch' Issue

I recently got my ham radio license. More on that in a different post maybe. For this post: The Explorer QRZ-1 handheld transceiver has a weird sort-of-bug and I think I figured out how to fix it.

TL;DR

If you programmed your Explorer QRZ-1 in CHIRP and your saved repeaters are not breaking squelch, try this:

1. In CHIRP go to View -> Show Extra Fields
2. In your saved QRZ-1 config find the affected repeater(s)
3. Change the Optional Signaling option to OFF
4. Save the config and upload it to the radio
5. Done!

The Longer Version

qrz.com has a partnership with gigaparts.com to help new ham licensees get on the air with their Jumpstart program. They used to send you the Explorer QRZ-1 radio and some accessories completely free which was a solid deal. But times are tough and starting in February of 2025 instead of a free radio they give you a coupon code good for 70% off the Explorer QRZ-1 radio and a collection of accessories that you can order a la carte. Nonetheless it’s still a decent deal at around $20 for the radio plus a bit extra if you add some accessories, so I took them up on it. I selected an external mic and a USB-C battery. What I did not order was the $25 software that can be used to program the radio because there is a perfectly good FOSS alternative called CHIRP which I had already confirmed had a working driver for this radio.

When the radio came, I didn’t even really mess with it in VFO mode. I already have a list of local repeaters set up in CHIRP for another handheld transceiver I already had. I simply downloaded the default config from the Explorer, pulled the same repeaters in from RepeaterBook, tweaked a few settings on the radio and uploaded it to the radio. It seemed like everything worked fine and I even heard some chatter on one of the repeaters that night so I knew the radio was working.

The next morning I switched it on to listen to a daily net that I enjoy hearing … and … nothing! Something weird was happening … the light and icon that show that a signal was detected were coming on, but no sound was coming through. It was as if the squelch was stuck on. In fact I found that if I held the monitor button, I could hear the net, but nothing else seemed to work.

After doing a bit of searching around, I discovered that this was not a unique problem. Here’s one blog post that I found, and a Reddit post about similar behaviors.

I tried the various workarounds I found. Disabling the dual-watch setting via CHIRP (or the radio menu) did not help. Messing with the Tone Mode setting and manually setting the PL Tone for the repeater did work. Pressing the PTT button did seem to work but then you basically have to ‘kerchunk’ the repeater which is kind of considered to be bad operation. Running the PL Tone Scan also worked (as long as there was a signal coming through long enough for the scan to reach the correct PL tone). However in both cases it would break again if you switched the radio off or even went to a different memory pre-set and came back. Also the one time I tried to key up and check in to the net after using one of these workarounds, the net controller did not call me back. It’s entirely possible that someone else stepped on me or maybe I wasn’t in a good location, but it made me think something was also amiss on the TX side as well as the RX side.

In any case I wanted to see if I could sort this out. I’m a hacker! I fix things! Maybe I could figure out what was going on and fix the CHIRP driver. My research told me that the Explorer QRZ-1 is a clone of the TYT TH-UV88 and it seemed like people programming that radio with CHIRP were not having this issue. Digging into the CHIRP drivers I found that the QRZ-1 and the TH-UV88 both use the TH-UV88 driver, there are just a few places where there is a conditional that does something different if the radio is a QRZ-1. None of those items seemed like they would have anything to do with the issue I was seeing. As far as I could tell there was no indication that the driver would be the source of the issue.

So then I went poking around in CHIRP itself. Maybe there was something I could do in there? I compared my QRZ-1 memory configs with my other radio’s memory configs…everything seemed identical. I looked around in all the menus and that’s when I noticed under View there as a Show Extra Fields option. With this enabled, some additional columns appeared in CHIRP. Interestingly, the extra columns for my other radio were different than the extra columns for my QRZ-1.

What immediately jumped out at me on the QRZ-1 config was the Optional Signaling column. Most of the memories had OFF selected. But a handful of repeaters, including the two repeaters that I had confirmed were having this issue, had something else selected. Some had DTMF selected, some had 5TONE. I figured it could not hurt to try, so I set them all to OFF and uploaded the modified config to the QRZ-1.

Next morning I went to tune into the net and it worked exactly as it should! I even keyed up and checked in successfully. It has continued to work after switching the radio off, or changing to a different memory or frequency.

Maybe you’re having a different issue but for me this seems to have solved it completely. Maybe someone already figured this out, but I had not seen it anywhere, so I am posting it here in case anyone else finds it useful.