TRX-1 Signals Stop Coming In Until I Stop & Restart Scan

[Neutrino222]

TRX-1 Signals Stop Coming In Until I Stop & Restart Scan. Has anyone had this issue, and how did you correct it? Note: On my second TRX-1.

Current setup: TRX-1 USB plug powered. LMR 400 coax going to yagi antenna tuned to 400-470 mhz. Headphone jack going out to speaker (sill haven't found the issues with the speaker not working) scanning a set of frequencies that have a range of modes: DMR, FM, NFM, including pre-set and 'search' privacy tones - maybe this is too much for the scanner to handle?

 

[tvengr]

A bad SD card can cause all kinds of strange problems. I would change the SD card to eliminate that possibility before doing any other troubleshooting. If your other TRX-1 is available, swap SD cards between the 2 scanners and see if the other scanner has the same problem.

 

[Neutrino222]

A bad SD card can cause all kinds of strange problems. I would change the SD card to eliminate that possibility before doing any other troubleshooting. If your other TRX-1 is available, swap SD cards between the 2 scanners.

Are you saying that TRX-1 is scanning directly from the SD, rather than loading the frequencies into a temporary internal memory for scanning?

 

[tvengr]

The scanner is totally controlled by the information on the SD card. Swap the 2 cards and see what happens. I have seen scanners completely dead due to a bad SD card. No backlight and no display.

 

[Ubbe]

It loads everything in memory but the data on the SD card needs to be without any read errors. It only reads or writes to the card when you change scanlists or switch to search and similar things and when you do audio recordings of course.

The TRX-1 seems to be more powerful than TRX-2 as it loads and validates the exact same programming 3-4 times quicker. The TRX-2 always have some recordings trashed that Windows need to fix but I haven't noticed that with TRX-1 and its USB function also works perfect, that the TRX-2 struggles with. The TRX-2 also has issues in VHF that the TRX-1 doesn't seem to have when used with the same antenna splitter. The squelch function also works much better. The only negative are that the volume dial on the top of the scanner are only a squelch adjustment and volume change has to be done from the arrow buttons.

/Ubbe

 

[Neutrino222]

The scanner is totally controlled by the information on the SD card. Swap the 2 cards and see what happens. I have seen scanners completely dead due to a bad SD card. No backlight and no display.

Right. I'll change the SD card, and report back. ;-)

 

[n4jri]

TRX-1 Signals Stop Coming In Until I Stop & Restart Scan. Has anyone had this issue, and how did you correct it? Note: On my second TRX-1.

Current setup: TRX-1 USB plug powered. LMR 400 coax going to yagi antenna tuned to 400-470 mhz. Headphone jack going out to speaker (sill haven't found the issues with the speaker not working) scanning a set of frequencies that have a range of modes: DMR, FM, NFM, including pre-set and 'search' privacy tones - maybe this is too much for the scanner to handle?

As for the variety of stuff you're scanning: Definitely not too much for the scanner to handle. I have two TRX-1's that I fill up heavily, and they do a great job. Could be another SD card situation.

As for the speaker, note that the headphone is a stereo (TRS) jack, so there could be a possible issue if your external speaker has a mono (TS) plug. This would likely short right channel (ring) to ground (sleeve) in a stereo device, and in the TRX, I suspect that it shorts your entire audio output to ground, presuming that tip and ring are the same internal connection.

Some devices have circuitry that can sense between stereo & mono plugs and compensate, but I'm not aware of that being the situation on the TRX-1. In fact, I'm not sure that such sensing could even work on a mono device like this. (can someone here answer that question?)

I believe that the TRX-2 has separate outputs for headphones and external speaker.

73/Allen (N4JRI)

 

[Ubbe]

I believe that the TRX-2 has separate outputs for headphones and external speaker.

It's the same for TRX-1, separate amplifier channels, probably a stereo chip, for speaker and headphone and both can be on at the same time.

/Ubbe

 

[Neutrino222]

I changed the SD for a Sandisk U1. Still having this issue. There are times when it just doesn't pick anything up, even though there is activity. I tried keying-up my Mitex on 449 right next to it, but nothing, until I stop the scan and restart. Strange! Any ideas?

If I upload my config file, would you all care to take a look at it, and see if you can make out anything that seems off?

 

[Neutrino222]

As for the variety of stuff you're scanning: Definitely not too much for the scanner to handle. I have two TRX-1's that I fill up heavily, and they do a great job. Could be another SD card situation.

As for the speaker, note that the headphone is a stereo (TRS) jack, so there could be a possible issue if your external speaker has a mono (TS) plug. This would likely short right channel (ring) to ground (sleeve) in a stereo device, and in the TRX, I suspect that it shorts your entire audio output to ground, presuming that tip and ring are the same internal connection.

Some devices have circuitry that can sense between stereo & mono plugs and compensate, but I'm not aware of that being the situation on the TRX-1. In fact, I'm not sure that such sensing could even work on a mono device like this. (can someone here answer that question?)

I believe that the TRX-2 has separate outputs for headphones and external speaker.

73/Allen (N4JRI)

Thanks! If I change the IF to HP & SP, then the internal speaker starts up, and I hear the key beeps and the hissing, so the speaker is working. It just won't work when IF is set to OFF, which is the normal operating function for the internal speaker. Any ideas?

 

[n4jri]

Thanks! If I change the IF to HP & SP, then the internal speaker starts up, and I hear the key beeps and the hissing, so the speaker is working. It just won't work when IF is set to OFF, which is the normal operating function for the internal speaker. Any ideas?

According to Ubbe, headphone & internal speaker are separate amps, which makes sense given that their levels can be set independently. So if you change the IF output to HP & SP, it makes sense that your internal speaker works. Does your internal speaker also work when you unplug the external speaker from the headphone jack?

For your external speaker, however, I worry that a mono plug is shorting your stereo jack. (the sleeve of a mono plug would short the ring of a stereo jack to ground) Do you have an adaptor that's stereo male/mono female? If so, plug it inline between your headphone jack and external speaker and see if the situation improves. Also note that your headphone amp likely isn't designed to power a 4- or 8-ohm speaker to reasonable listening volume. If you use an external speaker, I'd recommend an amplified model, and use an adaptor to match the headphone jack's stereo output to the speaker's mono input.

73/Allen (N4JRI)

 

[Ubbe]

Also note that your headphone amp likely isn't designed to power a 4- or 8-ohm speaker to reasonable listening volume.

I use a stereo plug's tip and sleeve on the TRX-1 and a 2 ohm speaker and its an incredible loud sound without any distortion at max volume. The amplifier chip are probably a 2W stereo loudspeaker chip that can handle low impedance speakers. It's about the same audio level with the same plug and speaker on a SDS100 at max volume, so could be a similar stereo amplifier chip, if not the same.

/Ubbe

 

[n4jri]

I use a stereo plug's tip and sleeve on the TRX-1 and a 2 ohm speaker and its an incredible loud sound without any distortion at max volume. The amplifier chip are probably a 2W stereo loudspeaker chip that can handle low impedance speakers. It's about the same audio level with the same plug and speaker on a SDS100 at max volume, so could be a similar stereo amplifier chip, if not the same.

/Ubbe

Are you aware (in either the TRX or SDS) of either short-circuit protection or mono plug sensing in the headphone circuit? Given that speaker vs. phones vs. both is a programmable 'decision' for the radio, I'm wondering if some reaction was triggered in Neutrino222's radio that that caused him to no longer get internal speaker on the default setting. I haven't had that issue using stereo earbuds.

73/Allen (N4JRI)

 

[Neutrino222]

Are you aware (in either the TRX or SDS) of either short-circuit protection or mono plug sensing in the headphone circuit? Given that speaker vs. phones vs. both is a programmable 'decision' for the radio, I'm wondering if some reaction was triggered in Neutrino222's radio that that caused him to no longer get internal speaker on the default setting. I haven't had that issue using stereo earbuds.

73/Allen (N4JRI)

Interesting! Maybe it's the Bluetooth speaker. I have a double-ended 3.5 stereo cable from the TRX-1 to the Bluetooth's AUX IN. I'll stop using the Bluetooth speaker, and see if the internal speaker comes back. In the meantime, I'll try to use a non-powered speaker.

 

[n4jri]

Interesting! Maybe it's the Bluetooth speaker. I have a double-ended 3.5 stereo cable from the TRX-1 to the Bluetooth's AUX IN. I'll stop using the Bluetooth speaker, and see if the internal speaker comes back. In the meantime, I'll try to use a non-powered speaker.

Actually, if you're using a stereo plug into the TRX, you're doing the right thing. I see no reason why it shouldn't feed a bluetooth just fine. My prior concern was that you might've had a mono plug on your external speaker, which is generally not a good thing to plug into a stereo jack.

Best to use a stereo cable. It's okay for both stereo & mono jacks. Mono plug into stereo jack is where the potential problem lies.

73/Allen (N4JRI)

 

[Ubbe]

Are you aware (in either the TRX or SDS) of either short-circuit protection or mono plug sensing in the headphone circuit?

It looks to be the switch in the jack, that usually are connected to break the sound to an internal speaker and divert to the jack, that instead are used as a signal to the CPU. So the audio are under software control. When using IF and Speaker&Headphone the audio are taken from a "discriminator" tap before any audio filtering and are also unsquleched. When used without the IF setting the audio are under squelch control and are taken after the audio filtering. So it could be either the squelch switch or the audio filtering circuit that doesn't work.

The power amplifier IC of modern times are both short circuit proof and over temperature safe and will be almost impossible to damage.

/Ubbe

 

[Neutrino222]

It looks to be the switch in the jack, that usually are connected to break the sound to an internal speaker and divert to the jack, that instead are used as a signal to the CPU.

Right! I see. I left it unplugged last night, no power and no Bluetooth speaker, and this morning after powering on, the internal speaker worked. I plugged in some headphones, and they worked. I unplugged them, and audio switched to internal speaker. I plugged and unplugged the headphones several times, but sometimes it took 5 or 6 seconds for the audio to switch over to the internal speaker. Perhaps the switch in the jack isn't engaging after being de-pressed for some time, and thus the software thinks there is something still plugged in.

 

[Ubbe]

A little splash of contact cleaner and then insert a plug several times and then blow compressed air if you have that in a can, might help.

/Ubbe