I purchased the HP2 specifically because my area uses a 700MHz Phase II system. When I monitor this system the audio is often very choppy and broken up - very hard to hear. I noticed in the Audio Options menu there are 2 submenus to adjust the P25 settings: P25 Filter and P25 Mode. Can someone tell me what these settings are for and if they should have any effect on decoding the audio?
HP-2 Poor Phase 2 Decoding
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marksmith
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They have limited effect on where the radio starts in decoding p25. Basically improving the signal (placement of the radio, better antenna) are really the only true things you can do to improve p25 decoding results.
I have an HP-2 and it does an excellent job decoding a local phase 2 700mz system. If you put it in the wrong location and use a lousy antenna on it the choppy reception and robotic voice can occur.
Do what you can to improve these two areas (if you have the extreme option you can use system analysis to find the sweet spot location and best antenna choices.
Changing the stuff on these hidden menu items go away each time you restart the radio and only do limited things to where the radio starts when receiving a signal to decode.
Mark
536/HP1e/HP2e/996P2/996XT/396XT/PSR800/PRO668/PRO652
I have an HP-2 and it does an excellent job decoding a local phase 2 700mz system. If you put it in the wrong location and use a lousy antenna on it the choppy reception and robotic voice can occur.
Do what you can to improve these two areas (if you have the extreme option you can use system analysis to find the sweet spot location and best antenna choices.
Changing the stuff on these hidden menu items go away each time you restart the radio and only do limited things to where the radio starts when receiving a signal to decode.
Mark
536/HP1e/HP2e/996P2/996XT/396XT/PSR800/PRO668/PRO652
I read in another thread that the 700MHz system I'm trying to listen to suffers from linear modulation simulcasting - multiple sites broadcasting the same traffic on the same frequencies. So it's like the scanner is getting overloaded and everything sounds garbled. Is there any way to alleviate this? I tried playing around with the attenuator but that doesn't seem to make a difference.
If you think that's the problem modify your favorites list to include only the site that's closest to you. That how I solved my P25 Phase II problem with Camden County, NJ's P25 Phase II system.
Reception and decode improved quite a bit. BUT I have a friend that is about equal distant from 3 sites and has had problems with his BCD536HP since day 1.
BTW I have the BCD536HP also.
Yeah that's the problem - there is 1 site that is closest to me, but within that site there are 6 locations simulcasting. So my scanner is being hit with the same transmission from 6 different directions. I found a site attenuator setting (which is different than the global attenuator) and that seems to be helping a little.
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... several friends and I are trying to tackle the Camco 700 LSM problem and we made a video of different scanners performance on Camco and Philly... we were in a spot with severe LSM... we found that a less sensitive antenna could help to isolate reception to one tower... we used a couple of different stubbies... the video is on the best scanner for Philly thread... the 1095, 536, 436, 996xtp2 and the 800 were tested but we didn't have an HP-2... we would be interested in hearing how the HP-2 works with regard to LSM...
The HP-2 overall does not handle LSM well. I was getting the usual garbled audio or no audio at all. I was able to alleviate the problem by doing 2 things:
1. I turned on the site attenuator (which is deifferent than the global attenuator). I believe this helps to reduce reception from some of the weaker sites in the simulcast.
2. I angled my antenna so that it is pointing sideways. So if you picture the HP-2 sitting on a desktop, I have the antenna sticking out sideways from the unit parallel to the floor, rather than pointing straight up. I believe this is also helping to weed out some of the weaker signals.
Reception is still far from perfect but this setup has helped.
I have the same problem listening to Fairfield PD with my 436. It sits almost upright on the dash of my work truck, and as I move around it's mostly good reception, but there are some spots that make it almost unreadable. Ironically, one of those spots is the parking lot of police headquarters. Newark fire sounds horrible sometimes too. I have only the West Orange simulcast active.
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What do you mean "RF environment"? In my situation I'm almost certain it's a LSM issue. If I listen to Site 1 I get garbled audio and most transmissions are unlistenable. Site 1 consists of 6 transmitters and my house is about right in the middle of those transmitters. If I listen to Site 2 which is about 15 miles away and only has 3 transmitters, I don't have the audio problems. So I'm pretty sure LSM is the culprit.
If you primarily use the HP2 as a stationary radio, you may be a good candidate for trying a small 3 or 5 element yagi or even better, a 700 MHz corner reflector that has solid panel reflectors to minimize signal ingress from the backside.
If you are handy at building things, you could probably slap together a small yagi pretty easy using plans found on the internet. A corner reflector at 700 MHz should also be pretty easy to build.
You don't really need either of these antennas for the gain they offer but rather the directional properties they both offer.
Something with the narrowest beamwidth you can find is what you are after if you are sitting in the middle of all the towers.
Aim it at the nearest tower that also has the greatest spacing in degrees from the other tower sites for your system of interest.
I've actually had good luck with a more distant system that was mostly blocked by trees (especially in the summer) using a direct aim. I found that I could get a much better signal by aiming at a nearby large building which picked up the reflection of the real signal. The aim was far enough away from the true signal that it nulled out the true signal and only picked up the reflection. When the leaves fell in the fall though, I had to play with aim again as the trees no longer offered any attenuation. That one worked best with a corner reflector.
Using a 12 element yagi, I had luck with a simulcast site by aiming the yagi 180 degrees off of true aim which blocked all but the strongest signal.
I've also had good luck using a yagi or corner reflector aimed maybe 20 degrees off of true aim. That was a system with all transmitters in one direction from me though. I was able to pick the northernmost tower and aim about 20 degrees further north than the tower. That 20 degrees was enough to null the other two towers signals and gave me perfect reception.
I'd try and build a yagi for testing. It does not need to be pretty looking but may give you an idea if a directional antenna will help.
The goal is to try and get signal from one tower only. If you have other 7/800 MHz sites in other directions, a yagi at those frequencies can be rotated with a cheap tv antenna rotor.
It took me a lot of experimentation before I found the best solution both in the radios used as well as the antennas.
The use of a directional antennas helped me more than anything though.
It also added the benefit of pulling in distant sites that I could not even detect with an omni made for just the band of interest.
Figured I'd throw this out there as I know directional antennas have helped many overcome simulcast distortion when nothing else worked.
Another idea is if you have an old TV antenna laying around. You would mount it vertically and try that. They are basically wideband yagi's but horizontally mounted for TV. Of course it needs to have been made to cover the old UHF TV band that went up to channel 83. A TV antenna may not have as narrow of a beamwidth that you really want but it may tell you if a directional antenna will work.
When RadioShack was still around, they sold UHF only TV antennas that could be mounted vertically by drilling two new holes through the aluminum boom. That gave you a directional antenna that covered from around 400 to 900 MHz or so. They were kind of a mix between a corner reflector design and a yagi. They had the large reflector wings on the back that you folded out. But the main boom was more of a yagi design. I guess that all helped give them their wide bandwidth needed for tv.
Your test only proves that the particular system may have issues. Again, my local LSM system does not. In fact, it sounds as good as a Motorola, and that's using the stock HP antenna on the scanner.
What I mean by RF Environment is what else is around you RF-wise. Cellular? Other PS systems in the same band? Paging in the same band? Mixing that ends up on one or more system frequencies? Active adjacent frequencies? (this is a big one for the HP due to the filtering - or lack thereof) Even the system design and surrounding terrain (hills, buildings, or lack thereof) can affect reception.
Any of the above can cause issues with any signals.
If it were strictly an LSM issue, all LSM systems would have it - not just some of them. So, logic dictates that it must be something other than just that mode that is the cause. (not saying it might not be a contributing factor)
If both of your sites (1 & 2) have multiple transmitters, both are most likely LSM systems, so your own example proves that it's more system-based and not a strict LSM issue, as your one LSM system works fine.
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... a beam type antenna will help as you can point it at a certain tower... when we ran the pretty sophisticated test, taking audio from jacks on the radio into a laptop on 5 different p-2 scanners (all but a HP-2 or 325p2) we were in LSM alley in Phila and had 5 bars on all radios... it was a LSM issue that COULD pop up anywhere in the country... it's not a system problem and it was from being between 2 towers and the scanners not handling it... note that we included a APX7000 in the test on Philly (800p1) and Camco (700p2)... it had no LSM issues...I am in the burbs outside of Philly... using a rooftop antenna I have no problem with LSM on any of my P2 scanners on any system (that I'm not close to)... I'm not surprised to see that the HP-2 would have reacted just like the others... we found a stubby antenna of lesser abilities helped but if you travel into a poor reception area it's going to miss transmissions... my conclusion... if you depend on scanning for your livelihood or public safety (until a company makes a scanner that works better) a professional commercial radio like the APX7000 is the answer... the cost???... it's out of range for the average Buffer ... the HP-2 looks like a nice radio if you are in the perfect storm (location, terrain, circumstances) to not suffer LSM...
phillydjdan
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A Motorola or a yagi on your HP. That's your solution, trust me. I know it isn't what anyone wants to hear, but it's the truth.
As stated Dan and Trent are in your area with lots of different scanners to test with.
Lucky me my working P25 sites are 22 miles away the next site is 25 miles I have 1 going 14 miles and then 8 miles so I do not see these problems.
Lucky me my working P25 sites are 22 miles away the next site is 25 miles I have 1 going 14 miles and then 8 miles so I do not see these problems.
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... it's really in the car moving around in the county or city where the system is or a radio on your hip walking around in the city where you get all this LSM... it really doesn't matter what brand of radio, they're all bad... an HP-2 is a nice radio as much as any other but under certain conditions no scanner works well with LSM and even low volume in noisy environments is a problem... we buy these radio to listen to them... you want a good radio that's clear, loud and gets every transmission... period... I'm still waiting... that's why there is so much praise for the Motorola radios... if you can afford it it's the "clear" choice...
marksmith
Member
Motorola basically built the environment you are wanting to inhabit so it will always be the most high quality solution, far exceeding what scanners can do at this point.
Mark
WS1095/536/996P2/HP1e/HP2e/996XT/325P2/396XT/PRO668/PSR800/PRO652
Mark
WS1095/536/996P2/HP1e/HP2e/996XT/325P2/396XT/PRO668/PSR800/PRO652
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... yes Mark... point well taken... Mot is out of reach for most people here both with cost and programing resources... some great threads going on elsewhere with undeniable video proof that it is not just the HP-2 that suffers from LSM... it's all brands... all models... (not 15 miles from the system (nearest tower) in a fixed setting but driving around in between the towers in the middle of the system... as more and more p-2 systems go on line in the years to come it will be very apparent to all.
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