Close Call ... Can the Algorithm be Changed?

[Dewey]

I just finished reading the "Close call issue" thread (SDS100/SDS200: - Close call issue) and it caused my mind to race. What I say next may not be 100% accurate, but it is my remembrance coupled with my interpretation.

I always felt that GRE's Close Call, I forget what it was called back in the early Radio Shack days, but I think the last used name was Signal Stalker, worked far better than Uniden's Close Call. Again, from my understanding, it was because GRE's Close Call (that's what I am going to call it for now) was truly a "RF detector" where Uniden's Close Call was more of a "scanner", meaning Uniden's Close Call could miss a hit if the hit were in a different band than the Uniden was searching at the time. I also remember Uniden having to create their Close Call this way (scanner -vs- detecting) because GRE had a patent on their Close Call method, sort of like the very early trunking days when Uniden/Greg Knox, beat GRE to the control channel decoding forcing GRE to have to monitor the voice frequency for trunking instead of the control channel - the early first GRE Pro-92 A & B model fiasco.

With all that said with Whistler now shuddered, what are the chances that Uniden can go to method of Close Call that GRE created?

 

[gary123]

My understanding is that the Uniden CC works by setting an attenuation value. Then any signal that passes that level is then "frequency counted counted" rather than sweeping the spectrum. Any signal being detected is then fed to the "discriminator' circuitry for processing like any programmed frequency would be. If the scanner recognizes the signal then the CC beeps and you hear it.

Many DMR (simplex ) or similar type of signal are not active long enough for the scanner to lock on to them and thus recognize them as a legit signal.

I do believe that Uniden could make some changes to improve CC operation. If they were to change the way the initial frequency is detected and maybe roll back the attenuation a bit they may be able to improve captures. Myself I use the waterfall option. It works exceptionally well for locating all types of modulation. All you need is to know the approximate band section to look at. By switching the bandwidth displayed you can rapidly home in on the unknown frequency.

 

[donc13]

if nothing else, that GRE patent or copyright still exists and someone owns it. You can not just use it now that GRE no longer exists.

 

[Ubbe]

Again, from my understanding, it was because GRE's Close Call (that's what I am going to call it for now) was truly a "RF detector" where Uniden's Close Call was more of a "scanner",

It's the total opposite. Signal stalker are a super fast frequency search in WFM that has to be over a certain signal level and if it detects a signal it switches to a slower NFM search withing that limited WFM bandwidth to pinpoint the frequency. Uniden are just a simple frequency counter that measures the frequency of a strong signal that has to be much stronger than any other signal.

So SignalStalker are much more sensitive, but reacts slower as it has to search a wide frequency spectrum so needs the signal to be present over a longer time. Uniden only needs a frequency counting to be stable over a one second time to make it a valid read.

Both systems serves a purpose and have their own value depending of the situation.

/Ubbe