Okay so if the BCD536 and HPI & II don't receive the 700Mhz simulcast transmissions well (or at all) , why do they receive the 800Mhz pretty good. I really like how the SD100 receives the 700, very crisp and clear.
Question about Simulcast
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doctordialtone
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Because every single set of circumstances is different.
internal/external antenna.......filters on the 100/200 that don't really exist on either the 536 or HP2, however my HP2 receives all just fine, same as my 200's. I don't have the 100 because I never cared for the proprietary battery. Reminds me of Nikon cameras. If it required regular AA's I would have bought it.
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700 megahertz P2 simulcast is very susceptible to linear simulcast modulation or LSM. Although the X36 series is P2 simulcast capable in my area they never did well with my P2 simulcast system which has one site called simulcast and 26 Towers all close together.
Another system near by me has two sites and multiple Towers all close together but it is a P1 System that is 800 megahertz but also very susceptible to LSM. The x36 work a little better on the phase 1 800 megahertz simulcast system but still have their problems.
It's the characteristics of the system, the type of system, how many sites it has that can actually be locked out to help with the situation, the distance between the towers to make LSM less serious or likely and even the way the system is calibrated.
The bottom line is LSM susceptible systems. Here in the east coast we are very susceptible to LSM on our simulcast systems P1 or P2.
The SDS 100 and 200 work flawlessly on our most difficult LSM susceptible systems and keep up with my Motorola gear. It's a whole different type of radio then the x36s or hp's.
If you don't want to go the dedicated radio or pager route then the SDS series works great on LSM susceptible simulcast systems.
As far as the proprietary battery on the SDS 100 it has been problematic with the bulging batteries and the initial small battery but it was established by upman that because of the power draw Double A's would just never cut it.
What I can't figure out is the proprietary SMA 100 antenna connection??? LOL.
As more and more cities go LSM susceptible simulcast, radios like the SDS series are the wave of the future.
Another system near by me has two sites and multiple Towers all close together but it is a P1 System that is 800 megahertz but also very susceptible to LSM. The x36 work a little better on the phase 1 800 megahertz simulcast system but still have their problems.
It's the characteristics of the system, the type of system, how many sites it has that can actually be locked out to help with the situation, the distance between the towers to make LSM less serious or likely and even the way the system is calibrated.
The bottom line is LSM susceptible systems. Here in the east coast we are very susceptible to LSM on our simulcast systems P1 or P2.
The SDS 100 and 200 work flawlessly on our most difficult LSM susceptible systems and keep up with my Motorola gear. It's a whole different type of radio then the x36s or hp's.
If you don't want to go the dedicated radio or pager route then the SDS series works great on LSM susceptible simulcast systems.
As far as the proprietary battery on the SDS 100 it has been problematic with the bulging batteries and the initial small battery but it was established by upman that because of the power draw Double A's would just never cut it.
What I can't figure out is the proprietary SMA 100 antenna connection??? LOL.
As more and more cities go LSM susceptible simulcast, radios like the SDS series are the wave of the future.
You're using the term LSM incorrectly. LSM is a form of QPSK modulation developed by Motorola; it is not the term used for describing simulcast distortion or multi-path.
Scanners are not "susceptible to LSM", they are susceptible to simulcast distortion or multi-path from LSM, or H-DQPSK, or other QPSK types of modulation.
Ok, so I understand you receive 700 Mhz just fine on your HP II? Can you tell me how? I hear just an occasional blurb of speech but that's it. I really like the HPII for mobile monitoring too. I wasn't too thrilled when they came out with the proprietary battery on the SD200 but I bought a second battery and an external battery charger pack when I'm out and about.
I can't figure the SMA antenna connection either, what the heck? Why not just put a BNC on it to avoid having the BNC adapter to run the antenna of choice
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Not to go off topic here but it was done to meet a waterproof specification or requirement. It's more like water resistant.
Most regular SMA connections on antennas won't work but there are some that do or you can shave some rubber off of antennas with a razor blade and they will fit.
Remtronix has made an SMA and a separate SMA 100 antenna to meet the needs sds100 users.
If you Google the subject it will lead you to RR threads that explain why they made the proprietary connection and the waterproofing Etc.
Most regular SMA connections on antennas won't work but there are some that do or you can shave some rubber off of antennas with a razor blade and they will fit.
Remtronix has made an SMA and a separate SMA 100 antenna to meet the needs sds100 users.
If you Google the subject it will lead you to RR threads that explain why they made the proprietary connection and the waterproofing Etc.
That's right, I forgot the water proofing! I think for the money they charge, a Blue Tooth system would be included
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Yes technically you are right, splitting hairs, I should have used the term simulcast distortion... I live in Bucks County, Pa that has a particularly difficult P2 700 megahertz simulcast system. When the system came online in 2015 no P2 capable scanners could pick it up properly in some parts of the county and most serious listeners went to unication or Motorola, my apx 7000 works great for me especially in the southern part of the county where towers are very close to each other. My SDS radios keep right up with the Motorola except of course for the volume punch.
I was making it simple since no one had mentioned LSM, my 50 plus years of continuous monitoring gives me a pretty good understanding of what we're talking about.
For the o p back when we were trying to pick up difficult simulcast systems with simulcast distortion there were many methods that were tried including drilling a hole in a paint can and sticking the antenna in it or people also used paper clips and the comet miracle baby CH - 32 antenna. It was a theory of a less efficient antenna would work to try to isolate one Tower.
That concept led to people using yagi antennas which are directional and pointed towards one particular Tower to try to isolate the signal. Often we would hear stories of people two counties away who would pick up the simulcast system very clearly because they were only listening to one tower because of the distance.
If you look up LSM in Wiki there is lots of information that'll explain the concept. Also if you Google the subject it'll take you to many threads that were active in 2015 on how to try to pick up P2 simulcast properly using the x36 or HP radios. A pretty familiar theme was... Location, location, location. LOL.
LSM is unable to be decoded properly in a multi-path reception simulcast enviornment, by the HP or earlier Uniden scanners. Hows that GTR? 
Also, the current RCS uses "wide" simulcast modulation , which is different.
Paul
Also, the current RCS uses "wide" simulcast modulation , which is different.
Paul
Exactly, both my 996P2's & 536HP receive 700/800MHz P25 P1 simulcast just fine, every bit as good as the SDS200 I had. I don't have P2 yet in my area so I can't speak for that.
Because BNCs suck when used where there is a repeated side to side flex and become loose.
I think that's primarly the case with cheap cast one out of CHINA. Quality Amphenol BNC connectors have never been a problem for me. They've worked for the military for decades.
Hit_Factor
Member
The SMA is not proprietary, the case and antenna are proprietary.
It takes just a few seconds to ream out the case opening or reduce the diameter of a third party antenna to make it fit.
Of course, consider how important water resistance is for your application first.
TailGator911
Silent Key/KF4ANC
I can see how the waterproofing would be beneficial to campers, hikers, boaters, but how many scanner enthusiasts stand outside in the pouring rain listening to their SDS100s? Even most SkyWarn guys I know (and myself) stay in their cars while monitoring the local repeater frequencies during severe weather conditions. I've often wondered about the waterproof casing Uniden has used for the SDS100, as it is the same (or close) case that is used for one of their vhf marine radio models. Same waterproofing, O-rings, etc? Hmm.
JD
kf4anc
JD
kf4anc
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Yes Hit Factor, I agree, I have a huge Ziploc bag of SMA antennas from the other Bearcats and Icom's... I have been able to shave down a few with a razor blade to fit just fine on the SDS 100. I didn't want to modify the case itself. I have a few sma's that actually fit okay and make the connection without any modification...
JD, I agree that the last thing we're going to do is take out the sds100 and allow it to get wet. We will do everything we can to keep that from happening but from what I've read, you're right, this the same case from a Uniden marine radio...
I think it ended up working pretty good but I don't think they anticipated it would end up having such a fat butt LOL.
Simulcast on my HP2 is the result of what realtors tell everyone when buying or selling:LOCATION, LOCATION, AND LOCATION!
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