Scanning Speed

[SSdudley2020]

Is there a way to increase your scanning speed on a SDS 100?

 

[doctordialtone]

Is there a way to increase your scanning speed on a SDS 100?

No.

You can only lessen the number of things it scans.

 

[Reconrider]

The sds100 is 80/s channel scan. The less you have, the better you are in the currently scanning loads.

 

[wtp]

it is the old 'the more you want to scan, the less you get to hear"
i use a 396XT for only my county and a 396T for everything else.
so the answer is to get more radios.

 

[Reconrider]

it is the old 'the more you want to scan, the less you get to hear"
i use a 396XT for only my county and a 396T for everything else.
so the answer is to get more radios.

Can confirm. Have 4 scanners going all the time lol. trx1 for local analog systems
sds100 for state p2 simulcast system
sds100 doing a search on my local towns businesses from the FCC
and a 2nd trx1 doing a search on the towns around me businesses and local. Don't really care much if I pick up anything or not just doing this one for the HAHAs

 

[ofd8001]

Well. . . That depends with regard to how much you are scanning.

If all you are scanning are conventional frequencies, yes the more you attempt to hear, the less likely you are to hear something. You can do the math figuring transmission time, etc.

On trunked systems, that's a whole 'nother thing. These are not scanned like conventional frequencies. Only the control channel is "listened" to. When channel grants are detected, the scanner looks at the list of desired channels to monitor, if there is a match, then you hear the traffic.

So on trunked systems, monitoring 1 or 101 talkgroups has equal speed and you are no more likely to miss a transmission.

 

[wtp]

and if you want to listen to 2 or 3 trunked systems how much time is lost to 'listening' to the control channel ?

 

[ofd8001]

About 2 seconds per site unless you increase hold time.

 

[RandyKuff]

Is there a way to increase your scanning speed on a SDS 100?

If your guaging scan speed from watching the display it's not really valid...
The display doesn't respond fast enough...
Scans faster than what you see the display doing...

 

[wtp]

for ofd8001. yes, absolutely.
and the big question many have is "why can't i hear the reply"?
because you are stuck in a 4 second time warp is the answer.
and i also have other older radios listening for the analog stuff so i can hear my counties trunked system.

 

[sallen07]

So on trunked systems, monitoring 1 or 101 talkgroups has equal speed and you are no more likely to miss a transmission.

That's not true, but it has nothing to do with "scan speed".

If you are listening to a busy system that has everything from sewer&water, animal control and snow plows all the way to fire/ems and police, then monitoring 101 talkgroups DOES make it more likely that you'll miss a transmission ... or at least the transmission you want to hear!

On the other hand, if you only listen to the 20 TGs that are used by emergency services (and do it in 'scan' mode) you are more likly to (for example) hear the acknowledgement to a Fire call rather than a snow plow calling out their location.

 

[Ubbe]

The sds100 is 80/s channel scan.

If you measure it it will be 45ch/s. It used to be 80ch/s and more using the olders firmwares but for some reason Uniden set it to a constant 45ch/s in later firmwares.

In most systems I monitor users first think about what they want to reply and then think about how to say it following radio procedures. It takes more than 2 sec until they key their transmitters. At best I can use 4sec but to really catch all replies I use 7 sec, but Uniden only gives you a choise of 5 and 10sec. If a dispatcher makes a call a responder needs to have his finger on the transmit button to be able to key up within 2 sec.

If the delay are set too short you have to wait for the scanner to go one full scan cycle to return to the same call and either that takes too long or the scanner stops on a call in another system and all you get are a chaotic mess of short transmissions making no sense.

/Ubbe

 

[JoeBearcat]

The scan speed varies depending on many variables - including RF density (from at least two aspects).

 

[ofd8001]

That's not true, but it has nothing to do with "scan speed".

Will you cite your source please? There are a number of previous posts that say the number of talkgroups in a scan list has no impact on the speed of scanning.

Conventional system scanning "listens" to each frequency for activity (assuming no Avoids, etc.) A trunked system doesn't work that way - as in it does not listen to each talkgroup for activity.

I would agree that having a large number of talkgroups may lead to missed traffic. That's only because someone is talking, thus slowing the scan to 1 channel per however many seconds the transmission takes, plus channel delay time and any internal housekeeping that may be needed.

 

[Ubbe]

The scan speed varies depending on many variables - including RF density (from at least two aspects).

The SDS100 are locked to do max 45ch/s, checked in debug log and with a single weak RF source from a signal generator. For some reason search are still the old numbers at 80 steps/s or more, or less, depending of RF interference.

In the 800Mhz band with a search with squelch set at 2 the interferencies doesn't seems to affect the search rate at all. In UHF it starts to hesitate at certain frequencencies and at VHF it really starts to slow down search at about 50% of the time. The interferencies are of such high distorsion and squeling high pitch noises that the squelch doesn't open but only stops briefly and then continues to search.

The audio interference where exactly the same in all bands VHF,UHF and 800Mhz, so it's probably something that happens in the receiver after the first mixer in the 1:st IF. If you only scan digital or mostly use 800Mhz band you'll probably never be aware of the problems with the receiver. These interferencies will blend with all signals it recieves and create mixing products that spread all over the frequency band.

SDS100 search rate

/Ubbe

 

[JimD56]

There is absolutely a way to increase scanning speeds, and it is on the "hush-hush". Buy more scanners.

 

[sallen07]

Will you cite your source please? There are a number of previous posts that say the number of talkgroups in a scan list has no impact on the speed of scanning.

I never said it had an effect on the speed of scanning. I actually said it was NOT related to speed of scanning.

I was replying to this statement:

So on trunked systems, monitoring 1 or 101 talkgroups has equal speed and you are no more likely to miss a transmission.

That's not true, and I went on to explain why. The more talkgroups you monitor on a busy trunking system, the more chance that you'll miss "interesting" transmissions. But like JimD56 said, the solution is to have more than one scanner and split the TGs.

 

[trentbob]

I agree that you can't increase the speed of scanning per se. A common newbie mistake might be programming in a Statewide Phase 2 system and listening to some local talk groups but never avoiding all of the sites from across the state when all they need is the one site they live closest to so as to hear those few local talkgroups.

Permanently avoiding all of the other sites in the system is certainly going to speed up scanning as the radio doesn't have to roll through all of them.

We know that the SDS radios don't have turbo speed scanning by any means but I vaguely remember a post by Paul before the introduction of the filters that the scan speed had been slowed down in one of their earlier firmware updates so as to improve performance.

 

[trentbob]

I never said it had an effect on the speed of scanning. I actually said it was NOT related to speed of scanning.

I was replying to this statement:

So on trunked systems, monitoring 1 or 101 talkgroups has equal speed and you are no more likely to miss a transmission.

That's not true, and I went on to explain why. The more talkgroups you monitor on a busy trunking system, the more chance that you'll miss "interesting" transmissions. But like JimD56 said, the solution is to have more than one scanner and split the TGs.

As we always said in The Newsroom... The more you scan the less you hear LOL.