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I have a new TYT MD-380; it works well for DMR channels, but on analog, the squelch doesn't seem to open when it should. I'm relatively new to ham and my first suspicion is user error, but it's tempting to blame it on poor hardware quality control.

What I've observed is that if the squelch is on, I can listen on the MD-380 and an analog-only radio (a Baofeng UV-5R) and hear nothing on the MD-380. If I use monitor mode to turn the squelch off, I do hear audio.

I've tried a number of combinations here:

  • Simplex and multiple repeaters
  • Carrier squelch and CTCSS (haven't tried DCS yet)

When testing against a repeater, I can transmit with either radio and be heard by others. The transmitting radio always drowns out RX on my non-transmitting one as expected, and I should be able to hear the roger beep from both radios, but I only ever hear it on the Baofeng, not the TYT.

I'll add that I have installed the md380tools custom firmware, but I'm pretty sure the squelch was an issue before doing so. (Yes, that may have voided my warranty and was probably dumb.) I'm not sure whether firmware would affect the squelch's ability to function.


Update: I've seen at least one reference which says the md380tools custom firmware might be the cause, and it's not clear whether the firmware has been tested on my generation of MD380 hardware. I'm going to try to get back to the original stock firmware (D014.009) if TYT posts it for download.

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    $\begingroup$ I don’t know anything about this radio, or about DMR. But I would try a factory reset, and reconfigure it from scratch (rather than from a computer) initially, to see if there is a problem with a ‘stock’ radio and no settings yet. There might be something esoteric stopping it from breaking the squelch that is hidden in a menu somewhere. Take a backup of the current settings first, if you’ve spent a lot of to,e setting it up so far. $\endgroup$ – Scott Earle May 28 at 15:40
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    $\begingroup$ If the radio doesn't have a squelch knob, then the squelch is controlled by firmware. $\endgroup$ – rclocher3 May 28 at 18:59
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Thanks all for the tips. Going back to stock firmware fixed the issue.

My radio reports hardware V05.01 and came from the factory loaded with firmware D014.009. I loaded md380tools onto it, which right now is based on D013, but I suspect that's incompatible with my hardware generation.

TYT sent me D015.001, which appears to fix the issue.

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Whenever you can hear when monitoring analog but not in normal operation, start by suspecting the way the CTCSS tones are set up.

  1. Make sure the Band Width setting is 25 kHz (for most analog repeaters, this corresponds to "WIDE" on the Baofeng).
  2. Make sure the CTCSS Decode is set to OFF or Carrier Squelch (CSQ).
  3. Make sure the CTCSS Encode is set to the value the repeater needs.
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  • $\begingroup$ Thanks for the tip, makes sense. Sadly, it's not changing my results. $\endgroup$ – K0SWE May 29 at 3:29

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