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ID51 decode

kc9zjf@...
 

I noticed my HT (id 51) is not always decoding the digital signal but if I roll it one frequency over and back to the hotspot frequency it decodes fine.  Would/could this be a setting with the UDRC that need adjustment?  I'm thinking radio, maybe ? it's not all the time 


Mike, KC9ZJF


 

You need to make very fine adjustments to the output level of the UDRC in alsamixer until it is reliable. The 5100 is the pickiest on deviation and the 51 is tighter than previous radios. 

On Feb 27, 2017 07:06, <kc9zjf@...> wrote:

I noticed my HT (id 51) is not always decoding the digital signal but if I roll it one frequency over and back to the hotspot frequency it decodes fine.  Would/could this be a setting with the UDRC that need adjustment?  I'm thinking radio, maybe ? it's not all the time 


Mike, KC9ZJF


kc9zjf@...
 

Thanks John, your support and response has been outstanding, 

very happy with the product thus far

kc9zjf@...
 

OK getting warmer,

Decode signal received great sound on the 51 and 5100 PCM -4db, ADC is 0db and LO is 11db

what I notice is it does not pick up the transmit all the time, sometime as much as every other, that's transmitting from HT or mobile through hotspot, it keys hotspot and looks like it is going thought but not received on the reflector, next goes through and reported as perfect audio received.

is it the LO drive controlling the analog through the system?  now that I have it receiving very nicely I don't want to mess too much with the settings as it is very touchy :-) 

It's so close to being ready to be left alone and run :-) 


Mike, KC9ZJF

 

Is this for a D-STAR hotspot? Which node radio are you using? ICOM IC-208H is known to NOT work with the UDRC-II.
Randy-W4LKS

On 2/27/2017 7:06 AM, kc9zjf@... wrote:

I noticed my HT (id 51) is not always decoding the digital signal but if I roll it one frequency over and back to the hotspot frequency it decodes fine. Would/could this be a setting with the UDRC that need adjustment? I'm thinking radio, maybe ? it's not all the time


Mike, KC9ZJF

kc9zjf@...
 

Sorry yes it is a D-Star hotspot, it is running through a Kenwood TM-V71


 

Maybe someone else can confirm that the TM-V71 works OK.  The symptoms you describe are just like the symptoms I saw when I tried the UDRC-II with my 208H:
  • Node radio would receive from the network and TX just fine
  • No alsamixer setting would allow reliable RX from my ID-51, TH-D74 or IC-2820
  • Sometimes, if I held the PTT for a long time it would begin to RX after a second or two.  But not reliably.

When I say RX, I mean the digital transmission being recognized by the G4KLS software.  The RX light on the node radio would illuminate, but the D-STAR transmission was not seen by dstarrepeater, not sent to ircddbgateway, and not logged.

Randy-W4LKS


On 3/1/2017 7:09 AM, kc9zjf@... wrote:

Sorry yes it is a D-Star hotspot, it is running through a Kenwood TM-V71

 

Mike

ADC controls audio to digital, eg, discriminator audio coming from the radio to the UDRC for decoding
LO is your primary audio to the radio, with PCM as 'Fine Tuning' -- optimally if you can keep PCM at 0 db and get the setting right with LO, then you are using as many bits as possible, but sometimes you have have to play with both.

As others have observed, some radios don't have a clean path from the radio's discriminator to the UDRC input -- if the path has any filtering or pre/de-emphasis then getting decode is impacted.  Focus your investigation around the discriminator audio path and ADC settings for receive.  ADC setting is not as crucial as LO/PCM if you have good discriminator audio.

On Wed, Mar 1, 2017 at 6:53 AM, <kc9zjf@...> wrote:

OK getting warmer,

Decode signal received great sound on the 51 and 5100 PCM -4db, ADC is 0db and LO is 11db

what I notice is it does not pick up the transmit all the time, sometime as much as every other, that's transmitting from HT or mobile through hotspot, it keys hotspot and looks like it is going thought but not received on the reflector, next goes through and reported as perfect audio received.

is it the LO drive controlling the analog through the system?  now that I have it receiving very nicely I don't want to mess too much with the settings as it is very touchy :-) 

It's so close to being ready to be left alone and run :-) 


Mike, KC9ZJF




--


John D. Hays
K7VE

PO Box 1223, Edmonds, WA 98020-1223