SDS100 Initial Review From Phoenix

[jonwienke]

An easier method would be to write down all the frequencies for the sites you're having trouble hearing, then enter them in Sentinel. Edit Profile, Miscellaneous tab, click the Review & Edit button under Intermediate Frequency Exchange. When you're done entering all the frequencies, save the profile and write to scanner.

Using the alternate intermediate frequency may get rid of images or other interference sources.

 

[cellphone]

Can you try turning on IFX for all those site's frequencies? (Hold on any channel, then FREQ/CHAN to direct enter the frequency, then F+7(IFX) to toggle IFX; repeat for each site frequency.)

Since the receivers are so radically different, it is quite possible that there could be images or other interference that could affect one and not the other. That it works when you leave the building is a big clue...and also points to a reception, not decoding, issue.

I did IFX for a all the frequencies on the RWC Thompson Peak site, and there was no change. I am still unable to receive that site.

One other note, my issue seems to be specific with 770mhz frequencies. I am able to receive 150mhz & 800mhz frequencies from other systems on Thompson Peak without issue.

 

[KR7CQ]

I did IFX for a all the frequencies on the RWC Thompson Peak site, and there was no change. I am still unable to receive that site.

One other note, my issue seems to be specific with 770mhz frequencies. I am able to receive 150mhz & 800mhz frequencies from other systems on Thompson Peak without issue.

Ditto, no change here, sorry I don't have better news to report.

cellphone: if you are as close to me as I think you are, we both have Shaw Butte between us and Thomson Peak. I have never been able to lock onto that site from my office with any scanner. I don't have that site in the G4, but I will have it there tomorrow for testing.

 

[UPMan]

If you manually hold on the site frequency (CHAN / FREQ / CHAN) with squelch at 0, can you hear any interference or other signal?

 

[cellphone]

Ditto, no change here, sorry I don't have better news to report.

cellphone: if you are as close to me as I think you are, we both have Shaw Butte between us and Thomson Peak. I have never been able to lock onto that site from my office with any scanner. I don't have that site in the G4, but I will have it there tomorrow for testing.

I'm not in my office today, so I am basing receive from home.

An update to my previous comment, event though I can receive 800mhz from Thompson peak, the performance of the 436 on the Maricopa County system (Maricopa County (Motorola) Trunking System, Maricopa County, Arizona - Scanner Frequencies) is perfect, and the SDS100 is almost silent.

 

[jonwienke]

One other note, my issue seems to be specific with 770mhz frequencies. I am able to receive 150mhz & 800mhz frequencies from other systems on Thompson Peak without issue.

That may be a sign of cellular interference.

 

[KR7CQ]

I'm not in my office today, so I am basing receive from home.

An update to my previous comment, event though I can receive 800mhz from Thompson peak, the performance of the 436 on the Maricopa County system (Maricopa County (Motorola) Trunking System, Maricopa County, Arizona - Scanner Frequencies) is perfect, and the SDS100 is almost silent.

Understood and agreed on MCSO. I haven't really brought that topic up yet, but reception of that system is absolutely abysmal on the SDS100 compared to the 436, truly bad. The main reason I'm mostly ignoring that, is that the phase 2 system is coming online soon as you know, and the SDS100 seems to do OK picking that up if you select the correct site...one site is even four bars from my office. But yeah, that legacy system just won't come in well on the SDS100, and as you probably know that's a fairly old smartzone system that can be monitored well with even the oldest digital scanners as I have verified this myself over the years. Strange...but I don't have solid testing / data to share, so this is anecdotal from me, at this point. I may do comprehensive testing with video soon.

 

[KR7CQ]

I did IFX for a all the frequencies on the RWC Thompson Peak site, and there was no change. I am still unable to receive that site.

One other note, my issue seems to be specific with 770mhz frequencies. I am able to receive 150mhz & 800mhz frequencies from other systems on Thompson Peak without issue.

For me, in my testing, 770 MHz reception is very poor on the SDS100. As I had mentioned a while back, even the 436 locks on to the simulcast G control frequency a few miles before the SDS100 when driving from outside of simulcast G towards those sites. And of course the G4 can lock onto simulcast G solidly from where my office is (apparently near your office east of the I17 on Peoria), a good ways from the simulcast G area...at well over twice the distance.

And as I've said, I believe this poor reception is due to interference...just a gut feeling there, no hard evidence or testing data to back that up.

*UPman: when monitoring the frequencies with squelch at zero I'm not detecting interference.

***Maybe what I should say my gut feeling is that "noise" is the issue, rather than "interference".

 

[cellphone]

Noise seems to be my problem. On the 770mhz frequencies I am testing, noise is almost always >5000 and frequently >10000.

On any frequency, when noise is below 1000, then I hear something. When it is below 500, then the SDS100 performs similar to the 436.

 

[KR7CQ]

Noise seems to be my problem. On the 770mhz frequencies I am testing, noise is almost always >5000 and frequently >10000.

On any frequency, when noise is below 1000, then I hear something. When it is below 500, then the SDS100 performs similar to the 436.

Similar results in general here as well, only I've seen noise numbers in the 20000 - 30000 range when things are really bad.

 

[UPMan]

High noise essentially means poor signal. Like listening to an AM station, as the signal gets weaker, the background hiss increases...Noise is the background hiss.

 

[cellphone]

High noise essentially means poor signal. Like listening to an AM station, as the signal gets weaker, the background hiss increases...Noise is the background hiss.

Are there software/firmware tweaks that can be done to get noisy environment performance of the SDS100 on par with the 436? Or is this related to hardware and filtering differences between the 436 and SDS100?

 

[Maddogz4]

Update - When testing my scanner I had been setting a GPS coordinate (also tried zip code) and barely received any transmissions (10 miles and 30 miles). From that point I would try holding on system (MPSCS for example in Michigan) and try to scan that way (still no hits). I would then hold a specific county (Macomb County (50) Sterling Heights as a example) and still no hits even if I locked on a channel that I was picking up on my BCD436HP. I have been busy so had not set up my FL so I finally set up a FL tonight with MPSCS and then Macomb County (50) Sterling Heights for example and now I am hearing transmissions crystal clear. I have also tried this with other close counties and also receiving plenty of transmissions. I am not sure why using a GPS coordinate with a range or locking on a site will hardly pick up anything? I also tried changing the delay time but no luck. Its not like I had too many service types on, I even had tried all service types on but barely picked up anything. I am learning all the time so not sure what I was doing wrong, I can only hear transmissions out of my FL. Anyways I am very pleased I am actually hearing things now, guess should of programmed my favorites from the start, lesson learned.

 

[KR7CQ]

Are there software/firmware tweaks that can be done to get noisy environment performance of the SDS100 on par with the 436? Or is this related to hardware and filtering differences between the 436 and SDS100?

Huge question right there, I'm wondering the same.

 

[jonwienke]

The issue with the scanner hanging on the control channel instead of switching to voice can probably be addressed via firmware. If firmware is used to adjust RF gain, then firmware tweaks can probably address images and other strong-signal problems.

One definite strong-signal firmware bug:
RSSI values higher than -60dBm only show as -55, -50, or -45. You never see -47 or -52dBm.

 

[UPMan]

I also got the report from the person that came over to compare performance. From that report, it appears that the issue with receiving the nearby sites is due to some RF interference from computer equipment (when moved away from the computer, reception went to 100%). Does that jive with your assessment?

The farther sites, as I mentioned in another thread, are likely right at the threshold of being receivable by anything...a area where I'd expect to see a lot of performance variation. 25 miles from inside a building is a pretty aggressive expectation...and that the G4 is picking up is probably a testament to it only having 3 bands to worry about (thus likely more robust front end filtering for each of those bands than is practical for a scanner that has such a wide receive range).

 

[Ubbe]

.... it appears that the issue with receiving the nearby sites is due to some RF interference from computer equipment (when moved away from the computer, reception went to 100%)....

And the 436 and G4 where not affected by that interference. Are the SDS100 poorly shielded, as was suggested earlier, or is it the SDR frontend receiver that are not as good as a conventional receiver and cannot handle the different kinds of nearfield interferencies that we all have now with routers, modems, computers, network and USBcabling and all those computer boxes in modern vehicles?

/Ubbe

 

[UPMan]

Completely different receiver designs are going to have different responses to environmental RF.

 

[WX4JCW]

I’m still not convinced it’s the SDS100 having the issue, I ran my G4 on Phoenix and had tons of issues, even to the point I missed transmissions on the G4 that my 536 picked up, whoever designed that system didn’t think it through


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[KR7CQ]

I’m still not convinced it’s the SDS100 having the issue, I ran my G4 on Phoenix and had tons of issues, even to the point I missed transmissions on the G4 that my 536 picked up, whoever designed that system didn’t think it through


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Not doubting you there. I had some issues originally but firmware updates seem to have solved almost all of them fortunately.

I met with another new SDS100 owner today for lunch in a different location and all of our results, and impressions about the SDS100 being no better than and at times inferior to the 436 were the same. We both agreed that interference was a likely culprit, and that we often see insanely high noise levels. We also both agreed that neither can touch the G4 when it comes to pulling in valley simulcasts other than the one we are sitting in the middle of.

My offer of a steak dinner still stands for anyone who can meet me and show me any scanner that can even come close to picking up the various Phoenix area simulcasts the way the G4 does. They are a world apart in performance for me, and for those who I've been meeting with and talking to in the valley and even other places.