STi Autoscan filtering

**MEM-TEK** · 06-23-2007, 11:04 PM

*****

**Buford T. Justice** · 06-24-2007, 05:32 AM

Originally Posted by MEM-TEK

Well, I went out late this Saturday night specifically to compare the STi's Autoscan mode to my V995's Autoscan mode. I've mentioned in a previous post that Autoscan mode on a V9XX or a RX-XX does not affect K or Ka band sensitivity in any way, except to add a very slight delay while the DSP circuitry decides if the received K or Ka band signal appeared to be real. And yet my STi's instruction manual plus others here have suggested that Autoscan mode on an STi does reduce K band sensitivity.

I did tests late this evening using my favorite trusty K band door opener location with an all but empty parking lot. Its true -- Autoscan versus Highway mode on an STi does engage a squelch which reduces the STi's K band sensitivity by about 3db. I repeated my tests several times in order to assure consistency in my results.

Well, I then did some driving around past several well known K band door opener locations with my STi in Autoscan mode. Its amazing how effective the 3db squelch is in reducing K band door opener false alerts, but only if the door openers are in locations which are set back a fair distance from the road (i.e., a really large parking lot between the door openers and the road).

The K band 3db squelch in Autoscan mode is fine for suburban driving conditions and even possibly for highway driving across really flat terrain, but I definitely would use Highway mode in all other situations away from cities or suburbs. That extra 3db of sensitivity in Highway mode would definitely be a ticket saver for any type of over the hill or around the curve K band radar encounters where instant-on is being frequently used.

Other STi owners, what do you think? Do my results seem to match what you have observed when using Autoscan versus Highway mode? In any event, the filtering on an STi definitely is different than on my V995.

--Michael

Nice little test MEM-TEK

You had mentioned

STi does engage a squelch which reduces the STi's K band sensitivity by about 3db.

I feel the STi does not reduce the sensitivity but through its "smart software" algorithms, the STi can maintain the maximum sensitivity while sampling each incoming signal and pass those it determines to be a real signal.

This is why I keep mine in Autoscan continuslly because I believe the STi will alert me the same distance with a real hit regardless if its in Autoscan or Highway because of the smart software algorithms sampling and not just a simple squelch.

I could be wrong, but for right now I'll run mine a few weeks in Autoscan to get a really good feel with all my K band hits then will switch over to Highway mode. Obviously someone who has a K band gun can perform a test now to determine this idea.

Again good test and thanks for the report.

**MEM-TEK** · 06-24-2007, 11:00 AM

*****

**nascar** · 06-24-2007, 03:13 PM

Totally agree. No one tests AutoScan. No one really knows what is going on with it.

Unless some Belscort Engineer wants to chime in, it is all speculation.

**below_the_radar** · 06-24-2007, 06:03 PM

MEM,

My results differ from yours, and are nearly identical for both Highway and Auto mode on K-Band. I live in a rural area where they planted a permanent "Your Speed Is" K-band sign about 1 mile away, down in a valley from where I exit the highway to go home each day. I know exactly which telephone pole I will cross when my STI indicates a first alert of K, or K1 signal strength. It does not matter if the STI is set to Highway or Auto, the detection range is for the most part identical. I have felt that Auto mode has provided a slight gain however. I have confirmed this with other stationary encounters as well. I do believe the STI's Auto filtering is different from my X50 however. The STI seems to set itself to the maximum sensitivity threshold, rather than the traditional fixed City is higher, Highway is lower mentality, or by adding additional checking over time to verify the signal is real algorithms. It almost appears that it monitors the noise floor, and sets itself for the maximum sensitivity and minimum time to alert on K and Ka bands. ( I don't run X, so I have no opinion there) So overall, Auto seems to be the way to run for quickest alert times, and maximum sensitivity, from what I have seen of the STI. (X50 stays in highway mode)

So no vote for me. IMHO.

**insidercw3** · 06-25-2007, 03:21 AM

Originally Posted by nascar

Totally agree. No one tests AutoScan. No one really knows what is going on with it.

Unless some Belscort Engineer wants to chime in, it is all speculation.

The STi's Autoscan works differently from other Bel units. In the STi Autoscan decreases X and K band sensitivity. It decreases X band senstivity by a significant amount and K band by just a few dB as Mem-Tek has mentioned. Autoscan's primary function is to prevent alerts from multiple door openers. In X band Autoscan will almost completely prevent alarms in the presence of mulitple X signals, until the signal reaches a higher threshold limit, ( very strong ) signal. It does the same with K band in the presence of multiple Ks but not as severely as with X. Real RADAR from LEOs is strong enough to overcome the increased "filtering" and will alert the user eventually. That's why users report that in Autoscan sometimes as they drive up to their local mini-mall the unit will burst into a strong X alert of 4/5 bars. The door's radar has overcome the increased threshold. Autoscan filters multiple Xs heavily and multiple Ks rather strongly, it filters single Xs heavily and single Ks just a bit.

**KnightHawk** · 06-25-2007, 05:27 AM

Originally Posted by insidercw3

Originally Posted by nascar

Totally agree. No one tests AutoScan. No one really knows what is going on with it.

Unless some Belscort Engineer wants to chime in, it is all speculation.

The STi's Autoscan works differently from other Bel units. In the STi Autoscan decreases X and K band sensitivity. It decreases X band senstivity by a significant amount and K band by just a few dB as Mem-Tek has mentioned. Autoscan's primary function is to prevent alerts from multiple door openers. In X band Autoscan will almost completely prevent alarms in the presence of mulitple X signals, until the signal reaches a higher threshold limit, ( very strong ) signal. It does the same with K band in the presence of multiple Ks but not as severely as with X. Real RADAR from LEOs is strong enough to overcome the increased "filtering" and will alert the user eventually. That's why users report that in Autoscan sometimes as they drive up to their local mini-mall the unit will burst into a strong X alert of 4/5 bars. The door's radar has overcome the increased threshold. Autoscan filters multiple Xs heavily and multiple Ks rather strongly, it filters single Xs heavily and single Ks just a bit.

Now we know how autoscan works with the STi.

Thanks to insidercw3.

**Buford T. Justice** · 06-25-2007, 06:50 AM

x2..lol

Like we have mentioned. We need some testing performed although everyones personal experience is all we have to go on and its helpful.

**thestaton** · 06-25-2007, 07:12 AM

Originally Posted by insidercw3

Originally Posted by nascar

Totally agree. No one tests AutoScan. No one really knows what is going on with it.

Unless some Belscort Engineer wants to chime in, it is all speculation.

The STi's Autoscan works differently from other Bel units. In the STi Autoscan decreases X and K band sensitivity. It decreases X band senstivity by a significant amount and K band by just a few dB as Mem-Tek has mentioned. Autoscan's primary function is to prevent alerts from multiple door openers. In X band Autoscan will almost completely prevent alarms in the presence of mulitple X signals, until the signal reaches a higher threshold limit, ( very strong ) signal. It does the same with K band in the presence of multiple Ks but not as severely as with X. Real RADAR from LEOs is strong enough to overcome the increased "filtering" and will alert the user eventually. That's why users report that in Autoscan sometimes as they drive up to their local mini-mall the unit will burst into a strong X alert of 4/5 bars. The door's radar has overcome the increased threshold. Autoscan filters multiple Xs heavily and multiple Ks rather strongly, it filters single Xs heavily and single Ks just a bit.

thanks!

**NOC** · 06-25-2007, 08:15 AM

yeah, i'm finding this as well I guess. mine goes off at almost every strip mall that has an auto door, but usually not until I'm right near it - meaning, it doesn't start in thousands of feet away as it would with a LEO CO. Only problem with this is you never know if there may be a LEO lurking somewhere around using IO. How would one know the difference? This actually happened to me over the weekend. I was on Rt. 206 coming from Trenton to Bernardsville, NJ. I was going through Hillsborough and there are lots of CVS, Walgreens, etc. STi goes off as I pass one and then I look over and there's a LEO also sitting in the parking lot with his radar on.