Close call on ubcd 3600 weak?

A place to talk about everything Radio and Scanning

Re: Close call on ubcd 3600 weak?

Postby friar » Mon May 01, 2017 9:56 pm

Six of Nine wrote:
friar wrote:Was in a store and assistant used radio about 25 feet away, and close call didn't pick it up.
Am I doing something wrong?
Thanks.


Hello, I have a BCD436HP (The US/Canada version of the 3600), and have verified several times that the 436 can miss a close call hit due to its standard antenna, which is not reputed to be good in VHF and UHF.
Check out Radioreference. :smiles:

Thanks for tip about antenna,will use the longer Watson one I have.
Only thing is I put in inside fleece pocket and it pokes me in the ear from time to time.
UBCD3500XLT now UBCD3600XLT
friar
 
Posts: 18
Joined: Mon Feb 06, 2017 6:46 pm

Re: Close call on ubcd 3600 weak?

Postby jimh » Wed May 03, 2017 9:47 pm

Fundamentally, Uniden Close Call will never work for DMR simplex/uplink channels: it's a characteristic of the technology they use. For close call to work, it needs to a relatively strong signal (it needs the signal to be about +15dB higher than the local noise floor) but it also needs the signal to be present for a sufficiently long period of time for the scanner to latch onto it. The DMR single slot TDMA frame is only around 30ms long, and that's too short for Close Call to work. That has all been verified publicly by Uniden. The repeater signal uses two slots interleaved, and that is sufficient for Close Call to work. In fact, all Uniden Close Call scanners are capable of detecting DMR repeater signals: but only the most recent digital units can both detect and decode DMR.

I have a number of BCD436HP's.....my experience is that the close call actually works pretty well (and better than any of the earlier Uniden models, including the UBC3500). That said, I've never used the stock antenna. Those that closely follow the RR threads related to a build quality/ internal noise issue on some early BCD436's will note that some people get better results when using a BNC antenna vs a SMA one. I suspect the 3600 will not suffer from this issue, so I'd recommend an SMA antenna (to avoid the tiny bit of extra loss caused by the SMA-BNC adapter), and one that is tuned to the band(s) you are trying to receive for best results.

As a side note, I think the chances of getting ANY firmware updates from Uniden for any non-US/Canadian Uniden models, such as the 3600, are very slim....if the experiences of our Australian colleagues is anything to go by.
jimh
 
Posts: 115
Joined: Wed Jan 22, 2014 9:13 pm

Re: Close call on ubcd 3600 weak?

Postby friar » Thu May 04, 2017 8:45 am

Thank you for such a detailed response,explaining a lot.
UBCD3500XLT now UBCD3600XLT
friar
 
Posts: 18
Joined: Mon Feb 06, 2017 6:46 pm

Re: Close call on ubcd 3600 weak?

Postby chlorinekid » Thu May 04, 2017 10:26 am

jimh wrote:Fundamentally, Uniden Close Call will never work for DMR simplex/uplink channels: it's a characteristic of the technology they use.....


Just wanted to thank you for this detailed explanation of the Close Call feature. Answers a few questions that I had. :thumbup:
chlorinekid
 
Posts: 1
Joined: Sun Apr 30, 2017 8:28 pm

Re: Close call on ubcd 3600 weak?

Postby jimh » Thu May 04, 2017 7:58 pm

No worries...happy to help, and thanks for the thanks !
jimh
 
Posts: 115
Joined: Wed Jan 22, 2014 9:13 pm

Re: Close call on ubcd 3600 weak?

Postby AndrewIrvine » Thu May 04, 2017 8:10 pm

How good is it at picking up DMR on simplex when searching, as opposed to having close call armed only?
200 miles in 2 days for my 3 children.
https://www.justgiving.com/Andrew-Gordon-50


Pro 2042, Pro 26, 3500XLT, BCT15X
Yaesu FT60-R, Yeasu 1900, Retevis RT3, Tytera MD380, Retevis H777, FDC160A, 278B, Puxing 888

"I'm listening.."
AndrewIrvine
 
Posts: 647
Joined: Thu Aug 01, 2013 10:45 am

Previous

Return to Radio and Scanning Chat

Who is online

Users browsing this forum: No registered users and 2 guests