Radio not receiving hotspot

Help with DMR issues
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kc8egv
Posts: 5
Joined: Fri Sep 23, 2022 11:57 pm

Radio not receiving hotspot

Post by kc8egv »

I'm slowly moving through the learning curve of the pi-star. Of all the modes I like DMR the most so that's where I am starting. I've ran into an issue that I can't figure out.
I've set up pi-start to the point where I can transmit from a DMR HT to the hotspot and the hotspot sends to the TG. Other stations can hear and respond to me fine. The pi-star activity shows receiving of the HT TX and forwarding it to the TG.
While receiving the HT does not hear anything even though the green light does indicate a signal (TYT MD380). I suspect that I'm not programming my HT correctly but so far everything I've tried has not worked. Below is some of the settings how I programmed one of the TGs connecting to the hotspot.
Thanks in advance for everyone's help!
Bryan, kc8egv

Scan List - None
Squelch - Normal
TX & RX Ref Freq - :ow
Admit Criteria - Always
Color Code - 1 (Matches pi-star)
Repeater Slot - 2 (Matches Pi-Star)
Privacy - None
AF6VN
Posts: 821
Joined: Fri Jul 20, 2018 1:15 am

Re: Radio not receiving hotspot

Post by AF6VN »

You don't really show enough to make a guess.

Getting the active channel LED would tend to indicate that you have the frequencies (Tx and Rx) set correctly (or so close that they bleed over).

Example Channel on my MD390:

Mode: Digital
Width: 12.5kHz
Scan: None
Squelch: Tight (hmmm, doesn't seem to be a problem since one isn't that far from the Pi-Star when operating)
RefFreq: Low & Low
TOT: 180
Rekey: 0
Power: Low

Name: DV HS US Nation(wide) (obviously not a factor)
Rx Freq: 446.2500
TxFreq: 446.2500
Admit Criteria: Color Code
NO [X] in subsequent rows

NO [X] in "digital data" group
Emergency: None
Contact: BM USA NationW (again, should not be a factor)
Group: DVMega General (have you set up a group list? -- this is different from Zone; Group list means you can hear all "channels"/TG in the group, even while tuned to a specific TG channel)
Color: 1
Slot: 2
Privacy: None
In-Call: Always

In Digital Contacts: BM USA NationW => Group Call => 3100

--
AF6VN
Dennis L Bieber
EA3BIL
Posts: 103
Joined: Tue Apr 17, 2018 11:45 pm

Re: Radio not receiving hotspot

Post by EA3BIL »

Sorry for delayed answer...

If the previous directions did not help, you may want to try this:
(Assuming you only use the HS for DMR)

Increase the value assigned to TX LEVEL at MODEM section available when acessing MMDVMHost in Expert, Configuration.
That value usually is set to 50%, and as far as I've seen, MD380, 390, 2017 and all their clones, need to have it slightly increased to value arround 54...56%.
Note:
Some Motorola WT do also need that setting.

If HS is used for diverse DV modes, value to be increased instead is DMRTXLevel (just a few fields below)


I hope this helps.

I wish my English is good enought for this explanation be understable...
73'Rafael.
EA3BIL
JN11an
kc8egv
Posts: 5
Joined: Fri Sep 23, 2022 11:57 pm

Re: Radio not receiving hotspot

Post by kc8egv »

Hi Guys!
Thanks for the info. I'm going to try to work on this again this weekend.
I've tried both of your suggestions and no luck so far.
When the hotspot transmits the green signal light comes on the radio but no audio. The hotspot is transmitting the signal according to the log.
I set the test channel (WW 93 - one with heavy traffic) up the same as AF6VN except for the Group List - I have none.
I can talk but I can not hear the audio.
I've tried this on two different radios, so it's got to be a programming issue somewhere.
Bryan - KC8EGV
Ohio, USA
KN2TOD
Posts: 262
Joined: Sun Nov 11, 2018 6:36 pm

Re: Radio not receiving hotspot

Post by KN2TOD »

Just a thought: turn up the volume - to the max for a start if necessary. The "volume/squelch" combo isn't always a smooth, linear function like you'd think a true volume control should be, so you may be right on the edge where squelch is killing your audio.

Also, try working with a known/manageable talk group: 9990, Parrot, for starters, and then expand to other TG's.
kc8egv
Posts: 5
Joined: Fri Sep 23, 2022 11:57 pm

Re: Radio not receiving hotspot

Post by kc8egv »

Here is the latest.
I programmed my DMR scanner and an analog to the TX/RX freq. When I TX from the radio, the DMR scanner hears it fine with good audio. The data signal is received by the analog one.
When the parrot responds, it keys up the hotspot. I can hear the data transmission on the analog scanner. The DMR signal strength meter moves, but no audio is received. The radio still indicates a signal with the green light.

The only mode on the hotspot that I have active is DMR so I don't think it's trying to cross-mode into something else. However, I'm not sure what DMR sounds like on an analog scanner. I did notice that the digital sounds do sound different when I compare my DMR radio TX and the TX of the hotspot.
The hotspot gives out a short high pitched tone before a steady data sound. The radio does not put out the tone in the front but when it firsts TX.

The HS is using CC 1 and TS2.
Bryan - KC8EGV
Ohio, USA
kc8egv
Posts: 5
Joined: Fri Sep 23, 2022 11:57 pm

Re: Radio not receiving hotspot

Post by kc8egv »

Update.
I have the same exact issues with Fusion mode. I have a feeling it's an issue with the pi-star TX mode somehow. Probly going to try a factory reset next. If that fails I'll see if I can return the unit for another one.
The TX data sounds are the exact same in Fusion and DMR mode so I know that can't be correct.
Bryan - KC8EGV
Ohio, USA
AF6VN
Posts: 821
Joined: Fri Jul 20, 2018 1:15 am

Re: Radio not receiving hotspot

Post by AF6VN »

kc8egv wrote: Sun Oct 30, 2022 3:38 pm Update.
I have the same exact issues with Fusion mode. I have a feeling it's an issue with the pi-star TX mode somehow. Probly going to try a factory reset next. If that fails I'll see if I can return the unit for another one.
The TX data sounds are the exact same in Fusion and DMR mode so I know that can't be correct.
The MD-380 doesn't do YSF -- only DMR.

The only way to get YSF is one of the cross-modes, which take the YSF data packet, strip the YSF header, then wrap it in a DMR wrapper. Between Pi-Star and MD-380 is all DMR.

You really need some sort of second unit for validation. Are there any DMR Repeaters in your neighborhood (or within a 60 minute drive). I'd recommend programming in those repeaters (and whatever talk groups are common to it -- track down the repeater operator's web page), then driving within range and checking there...

Note that the MD-380 is a pretty old model (I have an MD-390, MD-2017, and last fall grabbed an AnyTone D878UV-II Plus [though I haven't found a write up I'd trust on how /that/ model is unlocked]).

Getting a cheap second DMR HT is another option -- if both behave the same way, blame the hotspot. If one works and the other doesn't, blame the HT.

--
AF6VN
Dennis L Bieber
kc8egv
Posts: 5
Joined: Fri Sep 23, 2022 11:57 pm

Re: Radio not receiving hotspot

Post by kc8egv »

Thanks for the continuous responses...

Sorry, let me clarify.
The DMR radio works great thru local repeaters. I've been using two TYT HTs for several years without issues. They still work well on our local repeaters.
I have a Yaesu HT. It works just fine as a YSF radio. Using it for local repeaters without issues.
So, no problem with the HTs at all.

If you listen to the digital "noise" when the hotspot TXs, using an FM radio, you can tell that it does not sound like the digital mode being transmitted by the radios.

Also, don't forget, when I have my scanner in DMR mode on the same frequency, it decodes the DMR HT TXs just fine but when the hotspot TXs it does not. This tells me that the issue is with the HS TX.
Aside from resetting the HS, I'm going to also reach out to a few other local hams who have a hotspot and see if my HT will work with it.
Otherwise, I'm still thinking that it could be a hardware issue or a problem with the software that produces the digital TX.
Bryan - KC8EGV
Ohio, USA
AF6VN
Posts: 821
Joined: Fri Jul 20, 2018 1:15 am

Re: Radio not receiving hotspot

Post by AF6VN »

Okay... with that information I would blame the RF-board. The R-Pi is just passing the digital packets to the RF board for transmission. The only point where I can see the R-Pi being involved is if the serial port (or whatever GPIO) it uses to pass the data is faulty -- but that is unlikely as the R-Pi must be interfacing to the RF board during boot-up.

RF board swap would be my next approach.

--
AF6VN
Dennis L Bieber
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