Is there an equivalent of Squelch-line on DMR ?

Use this section to discuss Digital Amateur Radio operations, such as D-Star and other digitally-encoded traffic
Post Reply
Rob Johnson
Regular
Regular
Posts: 11
Joined: 06 Jan 2016, 00:06
Location: South-East England.

Is there an equivalent of Squelch-line on DMR ?

Post by Rob Johnson »

Hello All,

Is there a way of "picking-out" the equivalent of the squelch-line on a DMR radio, thinking of something like an MD785 here. It would be very useful for "cross-banding" (cross-technology-ing) between an analogue-mobile and a DMR-mobile radio. Could see nothing obviously marked when looking at a circuit-diagram of a DMR mobile earlier-on today. I did notice that there are "mode" and some other possible trigger-lines going to the audio-amplifier, if that's what they are. Do these lines carry-out "opening" the audio-amp up when a valid signal is received ?

Any information greatfully received. Thank you.

Rob.
User avatar
Scott_93
Super Member
Super Member
Posts: 448
Joined: 04 Oct 2009, 20:39
Call Sign: Sunray20Alph
Location: GBR/Overseas

Re: Is there an equivalent of Squelch-line on DMR ?

Post by Scott_93 »

I think it's in the Hytera service manual. Yes there is such a thing. In fact you can wire a Hytera cross pins and use it as a cross-band repeater just off the bat and if you put it through a cavity filter as an in-band repeater too.

Scott.
paulears
Top Poster
Top Poster
Posts: 1089
Joined: 10 Jun 2007, 22:41
Call Sign: G4RMT
Location: North East Suffolk
Contact:

Re: Is there an equivalent of Squelch-line on DMR ?

Post by paulears »

I've been experimenting with an optometrist controlled relay I bought from aliexpress - little pcb, with a sensor on the end of a short cable - I blutacked this to the RX LED on a radio and it closes the relay. My idea was a dPMR repeater with a couple of hand held, but the two cycles of codec travel mean that the usual digital latency gets doubled, and the vocoder quality is slightly worse. I didn't want to have to open the up to do it properly - and the relay switch proved to be the simple bit!
Freddie
Regular
Regular
Posts: 39
Joined: 09 May 2015, 13:19

Re: Is there an equivalent of Squelch-line on DMR ?

Post by Freddie »

paulears wrote:I've been experimenting with an optometrist controlled relay I bought from aliexpress
Why does your eye-doctor decide when the relay closes? :D
paulears
Top Poster
Top Poster
Posts: 1089
Joined: 10 Jun 2007, 22:41
Call Sign: G4RMT
Location: North East Suffolk
Contact:

Re: Is there an equivalent of Squelch-line on DMR ?

Post by paulears »

Never noticed that auto-correct - optometrist????? Letting the numpties at vision express run radios would be fun - took 3 optometrists to get my glasses prescription right!

Opto-isolated!
Rob Johnson
Regular
Regular
Posts: 11
Joined: 06 Jan 2016, 00:06
Location: South-East England.

Re: Is there an equivalent of Squelch-line on DMR ?

Post by Rob Johnson »

Hello All,

Sorry I have been away from here for a while and not replied to these informative posts. I will have a play with the MD785 that I have. I have now got the pin-out info for the 26 pin (why don't they use a NORMAL DB25 ?) on the back. Looks like the pin that does "speaker-enable" is the one to go for. I will report back. Thank you.

Rob.
Post Reply