SDS100/SDS200: Slow scan rate 18 channels per second.

[vikingegfd]

My sds 100 has all latest upgrades, squelch is set at 3, but testing with conventional channels , both AM or FM, indicate a scan rate of only 18 channels per second. (Compared to the WS-1040 which is supposedly 55 channels per second.) All other settings are default from factory.


What is the ideal channels per second supposed to be for this scanner?
If 18 cps indicates a faulty unit how do I contact Uniden to return for repair or replace?

Right now my new scanner remains a disappointment, I still have to use my old WS-1040 to be able to
listen to local radio traffic. I was hoping to replace it with the Uniden.

 

[jonwienke]

Have you ever updated the firmware?

You should be getting at least 80 channels/second on conventional if there is no traffic.

 

[vikingegfd]

As stated it has the latest firmware. 1.03.01.

 

[mtindor]

As stated it has the latest firmware. 1.03.01.

Take your antenna off, and then tell us if the scan rate returns to normal. If it does, you've got local interference plaguing you and causing your squelch [even set at 3] to not work well enough.

Mike

 

[jonwienke]

Actually you didn't state that. "Upgrades" is generally used to describe NXDN, DMR, and ProVoice, as opposed to firmware updates.

If your scanning includes trunked systems that use control channels (P25 and some variants of DMR and NXDN), be aware it takes the scanner 1-2 seconds per system site within range to scan the site and parse the current system and active transmission data from the control channel. So if you scan 2 P25 systems with 2 sites each in range, that will take 4-8 seconds of each scan cycle.

If you're only scanning conventional (non-trunked) channels, the most likely issue is that you have some frequencies that are set to digital that either have high noise levels, are constantly broadcasting some non-digital signal, or are constantly broadcasting a digital signal your scanner doesn't understand (possibly including ProVoice, DMR, or NXDN if you haven't purchased those upgrades). If a signal is detected on a channel programmed as digital, the scanner will pause and attempt to decode data from the signal. If it is unsuccessful, the scanner will eventually give up and resume scanning, but squelch will never open and this will slow down scanning considerably. Try making a copy of your conventional channels in a separate favorite list, and program the Audio Option to Search. Set squelch to 0, and manually scroll through your channels to see which ones have something other than normal atmospheric hiss/noise.

A programming or setting error is far more likely than a hardware problem.

 

[Ubbe]

You can't go by the display to judge a scan rate, it might not update fast enough.

What I do is to listen to the audio from the discriminator and have 100 channels filled in sequency, the ARC software usually has a fill function to do that, and inject a weak carrier from a signal generator and have the squelch fully closed, or program the channel with a subtone, and measure the time it takes between each blip in the noise from the discriminator.

Not many have a signal generator so instead you could program a frequency range you know are currently free from any transmissions and add one channel that you know always are active, like a datasignal from a trunked system, and then turn the dial to leave that channel and count the time it takes to return to the same data channel. With 100 "dummy" channels programmed it takes 1 second for a 100ch/s rate and 5 sec with a 20ch/s rate.

/Ubbe

 

[jonwienke]

Ubbe is correct that the display does not update as fast as the scanner actually scans, so you can't use the display refresh rate to judge scan speed.

 

[vikingegfd]

Antenna was off for tests which were performed on a test favorites list with only 20 FM conventional channels and then another test group with 95 AM aircraft channels. Display lag was not an issue based on unique department names that were used to time the tests.

 

[troymail]

Similar to Ubbe's comment - I tend to use a NOAA weather broadcast frequency (162.4, etc.) for my timing tests... Start the scan, wait for a weather broadcast, start your timer and scan again, etc.

During the tests, I also try different squelch settings to determine it's impact.

 

[jonwienke]

Export your favorite list(s) with your test channels, and post so we can see your channel settings.