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What is lowest BER folks have achieved with a Zumspot?

Posted: Sat May 26, 2018 6:27 pm
by aa3xn
After much tuning of RXoffset in Pistar the best BER i can achieve is 2.5%.

Radio is an Astro Saber which is on freq per service monitor.

What are others achieving? Any other parameters ro adjust in expert mode?

TNX

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Sat May 26, 2018 7:08 pm
by KB8AOB
I get 0.0% with a ZUMspot and a MD-380

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Sun May 27, 2018 12:50 pm
by KE0FHS
Same here. I typically get 0.0% with a ZUMspot and a Hytera AR-685.

Are you sure you have a ZUMspot (typically a white board)? There's a similar looking board that's a clone of the MMDVM_HS Hat called a JumboSPOT (green board with different architecture and different firmware) that is sometimes confused with the ZUMspot. I've seen reports of people having to enter really large RXOfffset values to get a JumboSPOT's BER to a relatively low value.

I've never heard of anyone having a BER issue like this with a ZUMspot, so if you do you have a ZUMspot, then you might want to contact the ZUMspot team as it's possible you have a defective board.

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Sun May 27, 2018 3:48 pm
by n9mxq
I get consistent 0.0 using either my Zumspot or Jumbospot, and with either HT. MD-380 or Anytone 868UV

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 2:37 pm
by aa3xn
Folks

Please read my question. I am asking about P25. NOT DMR . All radios mentioned in replies are DMR radios. I too get 0% BER with DMR. It is a legal, real Zumspot board bought from Bruce in Canada.

With DMR the RXoffset can be set to 0. At that setting the unit does not respond to P25 at all. When I move the RXOffset to around +950 I can get the unit to receive P25 (DMR will then not be received) and the minimum BER that I can achieve with P25 is 2.5%

i placed the question here because this is the P25 specific support forum

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 2:49 pm
by KR0SIV
Alright so I'm not crazy lol....

I kept seeing the MD-380 referenced and couldn't help but think uh... this is the p25 specific forum.
I have an XTS 5000 model 3, when in close range to my hotspot my BER is 0.0% it has been checked on a service monitor and I see you've done the same.

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 3:34 pm
by aa3xn
What have you set your RXoffset to for the XTS5K to work? Does DMR work at the same setting?

I was wondering if i had a near/far effect so tried the radio right next to the hotspot and 1 floor away, same results. Was going to try a 10 dB pad on the hotspot.

Since it appears Zumspots are no longer made, per Bruce, if i have a bad one i may be stuck.

When i try TG 10 with this BER the returned audio is passable, but not perfect

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 7:00 pm
by KE0FHS
The ZUMspot is available again (via HRO in the U.S.) and Jim, KI6ZUM, is now handling the production. You might want to try contacting via his email address, which is available on QRZ.

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 7:20 pm
by KE0FHS
KR0SIV wrote: Tue May 29, 2018 2:49 pm couldn't help but think uh... this is the p25 specific forum.
Guilty as charged. I open all posts from the Unread Posts menu link, and in this case I just read the large font subject and didn't look at which board it was posted in. Had the subject asked "What is lowest BER folks have achieved when using P25 with a ZUMspot?", I would've silently passed it by.

Re: What is lowest BER folks have achieved with a Zumspot?

Posted: Tue May 29, 2018 10:22 pm
by aa3xn
Very fair point. I went back and looked at the title of my post and noted the same (i.e., no reference to P25 in it). I just went with the title of the forum