SDS100/SDS200: SDS100 Scanning Issues

[Ubbe]

I think my Radio Shack Pro-2004 was the fastest scanner I've ever had.

It must have been another scanner that you had, because the Pro2004 had 16ch/s in fast mode and 8ch/s in slow mode.

I would imagine that they just have too much information to process per channel to determine exactly what mode they should switch to.

Scanner just checks for squelch, if a carrier are detected, then it stops scan and tries to check if the settings for the channel makes a match and if it's digital it has to stay a long time to try and determine the digital protocol. Scan rate are not related to the type of signal that the RF carrier has.

/Ubbe

 

[MStep]

I remember numbers "screaming by" on a desktop scanner I had at that time--- that may very well have been the fastest scanner I've ever had. I'll have to look through my storage area to see what else was running at the time.

 

[hulka]

My last scanner was a pro 96. It bit the dust and after a few years I got back into it some and purchased an 100. Later on bought the 200. To me it just seems to dwell on the TRS systems. Do not know if there is a lot more data to process hence the slower scan rates. I primarily listen to Phoenix Fire & PD and Maricopa County Sheriffs Office. Just started to monitor AZWINS.

 

[Nozzleman71]

I have a similar issue I hope someone can help me with. I have a 436 and my buddy has a 100. I programmed his 100 for him and it worked fine for a few months and then quit working. Today we updated the software and it still doesnt work. I even programmed my 436 and his 100 off my sentinel and my 436 works just fine picking up everything while the 100 sits quiet . Any suggestions ? I know it could be a wide range of things but Im baffled.

 

[RBMTS]

Does the SDS100 receive anything (like a local weather channel)? If no, try swapping the antennas. If yes, then it is a programming issue. The usual culprets are service selection, location setting, range, etc. If it is a trunking system then also check to make sure it is set to receive the local tower site (plus location, range, etc), that control channels are not locked out, etc.

 

[Nozzleman71]

Does the SDS100 receive anything (like a local weather channel)? If no, try swapping the antennas. If yes, then it is a programming issue. The usual culprets are service selection, location setting, range, etc. If it is a trunking system then also check to make sure it is set to receive the local tower site (plus location, range, etc), that control channels are not locked out, etc.

no it wont receive anything. I swapped the antennas on it and if the programming came directly from the same sentinel that i loaded the 436 with. ( Shouldn't all the groups/ service types and control channels all be ok since the 436 works perfect using the same sentinel program ?)

 

[Ubbe]

( Shouldn't all the groups/ service types and control channels all be ok since the 436 works perfect using the same sentinel program ?)

Yes. It could be that a soldering have cracked either at the antenna connector or at the J401 connector that connects the RF board to the logic board. If it's still in warranty then send it to Uniden, if not then check with jonwienke here at RR if he has time to fix it for you. Uniden scanner repairs

/Ubbe

 

[Nozzleman71]

Yes. It could be that a soldering have cracked either at the antenna connector or at the J401 connector that connects the RF board to the logic board. If it's still in warranty then send it to Uniden, if not then check with jonwienke here at RR if he has time to fix it for you. Uniden scanner repairs

/Ubbe

Thanks we will try that route. Thanks for the suggestions

 

[JoeBearcat]

I set up favorite list with a couple of hundred frequencies with a 25KHz step size to check the rate and also the debug files, my own and from other users, show that the SDS100 never goes faster than 45ch/s in scan rate, but are still the old speed at about 80steps/s when doing search between two frequencies that use the same step size.

The SDS100 are primary intended for scanning trunked systems that use simulcast. Trunked systems that use a control data channel will have the SDS100 to dwell at least 1,5 sec on that channel. Then the 45 or 80ch/s rate are of little concern. Only when doing conventional scanning of something like VHF air or mil-air and those kind of systems will it be more evident that it goes much slower.

There is also the problem with internal interferencies that slow down scan rate in conventional mode in SDS100. Without an antenna connected the 700-800MHz band seems to be pretty clean by just some hesitation in the scanning, but in the 400MHz it really slows down scanning a lot, not to mention 150MHz which seems to be the worst with the most internal interferencies that constantly stops scanning every one or two seconds.

/Ubbe

Everything you posted hints that it is RF energy (crowded band conditions) that is slowing down the SDS. Crowded bands will affect the SDS more than legacy receiver designs. This is affirmed by your findings on 800 MHz. What is the scan rate there?

 

[Ubbe]

Everything you posted hints that it is RF energy (crowded band conditions) that is slowing down the SDS.

No crowded band, just a a direct connection to a signal generator. 45ch/s are at every band incl the 800. I don't count the lower scan rate where the scanner hesitates and briefly stops on internal interferencies without any signal from the signal generator, it just works as a dummy load and do not receive anything from the airwaves.

Logically it seems that when the firmware where changed to make the debug routine sample at half speed, hopefully it was deliberately made and not a bug, the same timer where also reused in the scanner routine, slowing it down to half speed. Can't really see no other reason as the search rate are still unaffected and runs at full speed with pretty much the same capacity and functions as scanning mode are using.

/Ubbe

 

[JoeBearcat]

Thanks. I will look into this.

 

[Indianabrad]

I think my Radio Shack Pro-2004 was the fastest scanner I've ever had.

If you think that was fast, I over clocked my Pro-2004 with a crystal & it then scanned barely faster than a Pro-2006, Which nearly doubled the scan speed of my Pro2004 to 27.03 channels a second.. For your info the Pro-2004 was a slow slug at stock scan speeds of 8/16 (low/high scan button) channels per second. I also did at least a half dozen other mods to my Pro-2004 and I still have it today & listen to mostly ham repeaters on it. I'm truly glad that I'm not as miss-impressed at scan speeds as you are, b/c I could see on the first day that I got my Pro-2004 (in 1987) that it didn't scan very fast. And back to your point, you poor thing, the only way that could be true is if you haven't bought another scanner in over 30 yrs.