SDS100: Global auto filter guidance needed

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racing1

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I primarily listen to 800mhz phase 1 and phase 2 simulcast while stationary and mobile. Can someone explain what each filter setting accomplishes and which one should I choose to have the best performance?
 

allend

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One thing that I just noticed that a certain trunking Phase I and II system does not trunk in "Normal" Global Filter Mode. Only in "Invert" mode mode. What the heck is INVERT mode. Strange. Never had this issue with the BCD996P2 radio

But then if you leave Global Filtering in "Normal" mode then scanning is fast. If you leave Global Filtering in "Auto" mode than the scanner scans real slow. NOT GOOD
 

mancow

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Yes UPMAN mentioned that as it reevaluates each frequency.

Have you tried the other settings?
 

KevinC

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One thing that I just noticed that a certain trunking Phase I and II system does not trunk in "Normal" Global Filter Mode. Only in "Invert" mode mode. What the heck is INVERT mode. Strange. Never had this issue with the BCD996P2 radio

But then if you leave Global Filtering in "Normal" mode then scanning is fast. If you leave Global Filtering in "Auto" mode than the scanner scans real slow. NOT GOOD
I believe it was determined that "invert" was a LPF and "normal" was a HPF.
 

epilab

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Talked to Uniden customer suppot about front end overload and rf settings. As of now they have had no questions concerning the front end overload and offer no solution
 

mule1075

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Talked to Uniden customer suppot about front end overload and rf settings. As of now they have had no questions concerning the front end overload and offer no solution
Interesting I talked to them about adjacent channel interference before the filters became available so I am sure they have had questions. The filters have cured 95% of my adjacent channel interference and intemod on uhf/vhf.
 

N8TXX

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I believe it was determined that "invert" was a LPF and "normal" was a HPF.
It would be nice then, if they called the filters what they are (HPF and LPF) like they do on short wave transceivers. I have an icom ic7300 and the filters are awesome.
 

trentbob

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Just an observation with the filters for me. I have an SDS 100 and the money sitting in my pocket for an SDS 200 which of course is going to stay in my pocket for now.

I have one of those single site simulcast systems on the East Coast that has 26 Towers close together that you can't turn on and off. The only site you can manipulate is the one site called simulcast. Whatever the radio is calling for is transmitted by every one of those Towers at the same time, LSM nightmare.

The sds100 never worked on my system with obvious frequent missed and clipped Transmissions. I kept the radio because of the nxnd but it didn't get much use and to me it was just another turd on the pile of turds. LOL. Most serious listeners in my County use one of the two Alternatives as I do.

When these filters first came out, with some experimenting, I found that the invert filter worked on my hometown system and stopped the missed Transmissions. I keep Global on normal for most objects and it either improves or doesn't affect at all the performance. Some simulcast systems I have on invert and some conventional channels I found that no filter at all worked. You can imagine the feeling of finally being able to use the radio and program it fully.

I programed the sds100 exactly like I would the SDS 200. In a multi system environment of course you need more than one radio if you're going to hear everything but I put about 18 conventional channels of all types, some simplex and some VHF or UHF repeaters and scanned just those without any other system at all on the SDS 100. BTW, I have 3 very high rooftop antennas. Lots of clipped transmissions or totally missed transmissions that have nothing to do with filters. The thing just scans too slow and by the time it gets around to a reply it's too late to catch it. Add a system or two in there and you are missing a lot of traffic.

This update with the filters was a good one and in my case made all the difference with this radio.

Now I would love to see an update that gives us something I remember from the old days, it's called... Turboscan. Make the thing scan so fast that it's just a blur. Man that would really improve performance.

As I said before, because of these filters, I'm glad to have the sds100 now as it's smaller and lighter than the alternative that I use that pulls my pants down.
 

Ubbe

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Now I would love to see an update that gives us something I remember from the old days, it's called... Turboscan. Make the thing scan so fast that it's just a blur. Man that would really improve performance.
It's very difficult to do, or more likely impossible. The chip that are used as a receiver are not designed to scan frequencies with a high scan rate. It is supposed to search frequencies of television or sat frequencies and then store them and be used when somebody change channels on his tv or sat box. It becomes extremly slow if it also has to switch frequency band while scanning. The chip costs less than $10 so lets hope that the future Uniden SDS500 uses two chips, one scans and when it monitors traffic the other chip continues the scan and stops on next conversation, ready to take over the monitoring when the first chip stops monitoring. Standard dual VFO would also be possible. That would be the expected technology evolvement after this experimental test with SDS100/200.

/Ubbe
 

RonLittle

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I'm not a HAM and I have no idea what any of the filters do. (I'm also not messing with them) It would have been nice if Uniden had added a page or two listing the filters and describing the purpose and function of the various filters.
 

RonLittle

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I'm not a HAM and I have no idea what any of the filters do. (I'm also not messing with them) It would have been nice if Uniden had added a page or two listing the filters and describing the purpose and function of the various filters.
Can anyone give a filter list with descriptions or purpose, thank you.
 
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