News photographer ditches brand new 436HP, film at 11

[prcguy]

Testing without an antenna has no bearing on the sensitivity of the receiver, its more of a test on how well the radio circuits are shielded. If you test the 436HP against say a Thales MBITR or T25, the Thales radios will completely fail because the radio cases are machined from a solid block of aluminum and it won't pick up anything without the antenna connected.

At least do some kind of legitimate test before condemning a radio.
prcguy

I tested with NO antenna because the first P25 transmission received out of the box with antenna was full signal and garbled. Both scanners were identically handicapped as far as limiting the RF they were receiving.

Anyway, both with stock antennas exhibit the same performance variation. Taking the antennas off was the easiest way to verify "fringe" reception performance. I have a hard enough time moving the 396XT around trying to eek out voice traffic with zero bars in the field. Zero bars performance in a job where you have no control over your location in relation to the transmitting site is a very real concern.

Again, this point of view is from someone who makes a living off of these devices, not someone who listens as a hobby and whose location and physical actions are not governed by the audio coming out of the speaker.

Paul

 

[Anderegg]

I can see slightly desensitized receivers (536) in a mobile platform as beneficial, but the double hit of loss of sensitivity as well as a poor P25 decode algorithm, leads to a device that should never have a belt clip attached. The 996's in my work vehicle with 4.5db gain antenna take blasts from cell towers badly. They show full signal, but analog reception is sounds like -5 bars. I don't have that problem with the 396XT, which I use primarily with a 1/4 spike. It's main problem is pulling in distant faint signal systems. The XT's seem to almost have better P25 performance than analog, as long as I can make out analog voice, I am pretty sure I will be able to understand a P25 transmission on the same site as well.

I actually have to inch my car forward and reverse in order to get readable analog on my most distant site. I have to "tune" my parking spot via analog, because P25 can come in crystal clear on the 996's but analog could be just static.

I just got my HP ERR rate down to 12-28 by adjusting my thresh-level thingy to 12 or 13. Under 7 and over 14 result in just digital noise, no audio. 10-11 were getting me a bit too much motorboating/static at the beginning of transmissions.

Paul

 

[KevinC]

Nothing to add, but I'm guessing you are monitoring a 3600 mixed-mode system?

 

[Anderegg]

prc, I followed up that the variation persisted when the same stock antenna was utilized on both radios. I can test the HP against my 99's in the field tonight, hooked up to an identical spare BNC lead out of a Stridesberg multicoupler.

The official way I test antennas and radios is to lock in a control channel and place the receiver in various locations and see if one finds a large dead zone the alternate does not.

Paul

 

[Anderegg]

You are correct Kevin.

I hope the point of this post will be to evaluate the mission critical viability/usability of the 436HP vs the old 396XT, for those who really do care about every last ounce of reception. Once the radio is nailed down correctly, I can add my 2 cents worth to the official UPman firmware mod reception post, with correct formatting of course.

Paul

 

[ofd8001]

I actually have to inch my car forward and reverse in order to get readable analog on my most distant site. I have to "tune" my parking spot via analog, because P25 can come in crystal clear on the 996's but analog could be just static.

That's common when comparing digital and analog. With digital, you either have it good or you don't have it at all.

Imagine the "limit line" for a radio system. With digital, if you are one inch on the "good side" you'll hear it clearly. One inch the other way, you hear nothing. On an analog system, you'll get lots of static when you are that one inch on the good side.

I can hear a conventional P25 transmitter clearly, but see 0 bars on the signal strength meter on the scanner.

 

[Anderegg]

The problem I see here is my particular radio will be applying an already error filled decode algorithm to a "not as many bits making it through the air" desensitized receiver. That bit that could make the difference between that block receiving as all or nothing, will in many cases be contained in the signal that just isn't getting through to the decoder.

Paul

 

[KevinC]

Nothing to add, but I'm guessing you are monitoring a 3600 mixed-mode system?

You are correct Kevin.

I hope the point of this post will be to evaluate the mission critical viability/usability of the 436HP vs the old 396XT, for those who really do care about every last ounce of reception. Once the radio is nailed down correctly, I can add my 2 cents worth to the official UPman firmware mod reception post, with correct formatting of course.

Paul

It appears from others posts that 3600 mixed-mode systems may be problematic with the x36HP-series radios.

Others will probably disagree with me, but my 436 seems to work awesome on 9600 simulcast systems. So far I've tried it on the new Las Vegas system, STARCOM21 in Schaumburg and all of the City of Houston/Harris County simulcast sites with excellent results...but maybe I just got a real good radio.

 

[kd7eir]

I monitor both P25 Phase II simulcast sites and P25 Phase I non-simulcast sites here in Tucson, and I have no problems at all with my 436.

I am far from the only person with such results, which would logically indicate that the 436 is NOT the POS that some are making it out to be. Certainly for some people/locations it is not the right tool. For other people/locations it is the perfect tool.

One consensus seems to be that the 436 is primarily designed for digital systems rather than analog. Considering that the ultimate goal of the 436 was to bring Uniden into the P25 Phase II game, that makes perfect sense.

I am hoping that once all the WiFi/Siren/Analyze mess is cleared up Uniden can work on tweaking the firmware to improve the performance for ALL people/locations.

BTW - those saying that this is a HARDWARE issue are proven wrong by the fact that the 436 works just fine for many, many people. Keep in mind that those who are experiencing problems are many times more likely to complain than people who are experiencing no problems are to brag about it.

 

[Anderegg]

9600? Phase 2? What is wrong with Uniden, I want more effort put into AM, SSB, NTSC TV audio, a morse code button. What kind of company puts all their tech development into new systems that will be around 30 years from now, and not obsolete things we all love.

OMG, I feel so old. Another big reason I pulled the trigger on the HP was UPmans constant attention to the Uniden loyals, and the fact that it's just at the beginning of it's product life cycle and firmware process. the XT has gone as far as it's going to go.

Paul

 

[jonwienke]

I'm picking up stuff from 4 states (WV, MD, VA, and PA) from Martinsburg WV with my 436HP and a rubber duck. This includes WV-SIRN and VA STARS (statewide p25 systems) analog stuff from the PA turnpike commission, national park service traffic, 3 states worth of ham repeaters, and miscellaneous other stuff.

My problem isn't picking traffic up, it's winnowing it down to a manageable amount of channels I care to listen to that can be scanned in a reasonable amount of time.

And your test methodology is laughable. The only way to do a valid comparison is with a single antenna, a T fitting, and 2 equal lengths of identical coax going from the T to each radio. You also need to open squelch completely so that the test isn't biased by unequal squelch settings, and compare which radio demodulates the signal with the least static or garbles at equal volume levels.

 

[Anderegg]

Jon, how do you propose I test the two radios to your satisfaction? Not being sarcastic. I have a BNC T with two identical packaged Radio Shack coax and a rooftop antenna on a car. Typically I have a local 800MHz system, a near area system, and a distant system. Are you good with the concept of testing with the weakest signal? Since it's all 800 trunking here, I tend to always test the one I have the hardest time receiving, the distant control channel.

I also can drive 30 seconds and be directly under 2 different cell towers, one of which will nullify reception, but keep the talkgroups locked in with full unfluctuating 5 bars! I know UPman says they made these new radios less sensitive and more selective. I am thinking in a mobile 536HP application, the lack of sensitivity would be put aside for the ability to receive more in the shadow of all the damn cell towers every 100 feet around here! It's a trade off, do you want to hear the distant faint signals, or still be able to hear the local ones?

Paul

 

[JamesO]

Suggest the RadioShack 800 MHz antenna for the 436HP. I have been running these for years on all my handhelds. Most stock OE antennas are pathetic at best.

Not seeing the same issues you are with your 436HP, overall mine works pretty good from what I am seeing.

I have 396XT, 996XT, HP1E, 536HP and the 436HP.

Does Uniden have work to do on their firmware and decoding, YES.

Does the AGC function on the x96XT and x36HP or even the HP1, if someone can PROVE it does, I would LOVE to see PROOF and a white paper on how the AGC works and what and how the settings impact performance.

Uniden is working on the firmware for the HP1 and it is getting better, hopefully they are learning valuable things that can be applied to the x36HP units.

I can say I am SHOCKED at how Uniden is still trying to figure out and optimize the firmware for these radios. I think they have been complacent and only tested the firmware where it is written and it has not be critically tested and reviewed.

But I am seeing some things that are giving me hope. I am hopeful the will uncover something common on the X96T(XT) HP1 and the x36HP so they can release updated firmware for all of these radios that will decode far better than they have been.

I am currently running the latest Beta firmware in my HP1 and overall this is the best the radio has ever sounded. There are some bugs to still sort out, but I am hopeful they will make headway and get this sorted once and for all.

I am guessing you either have a crappy antenna, a scanner that has issues or you are monitoring a problem system that the x36HP has not been fully vetted against?

 

[jonwienke]

Jon, how do you propose I test the two radios to your satisfaction? Not being sarcastic. I have a BNC T with two identical packaged Radio Shack coax and a rooftop antenna on a car. Typically I have a local 800MHz system, a near area system, and a distant system. Are you good with the concept of testing with the weakest signal? Since it's all 800 trunking here, I tend to always test the one I have the hardest time receiving, the distant control channel.

Connect both scanners to the antenna with your T and identical cables. Lock both scanners to a single channel, set squelch to minimum (off) on both scanners, Adjust volume to equal levels, and drive around and see which scanner delivers the best audio under a variety of reception and interference conditions. Change channels or talkgroups periodically, just make sure that both scanners are listening to the exact same thing. Driving under cell/TV towers is a good test, as would be driving out in the boonies in a valley or under a bridge where reception is likely to be poor. In addition to the car antenna, try a rubber ducky with a BNC.

But the main thing is that it's a side-by-side comparison with both radios at equal volume squelch open on the same channel receiving identical electrical signals at antenna input. If listening to P25 mixed, set decode time to 0ms instead of 400ms so you're not chopping off the front end of analog transmissions.

 

[Anderegg]

I have all sorts of 3.5mm patching cables and a laptop in my car. I can hook both scanners up to the line in of my laptop so that one scanner is left channel, and one is right. I can then set squelch to 0 and drive around on the CC for awhile, then lock onto a talkgroup, digital and analog. It would easy to hear one or the other cut completely out that way, especially listening to the recording with headphones.

I know UPman said that the HP's are less sensitive for more selectivity than GRE's, but perhaps the same "trade-off" he speaks of was applied HP vs the XT line?

Paul

 

[JamesO]

Be careful with the idea of connecting something to the headphone connector on the x36HP.

I just found something yesterday that I need to follow up on where my 436HP when connected to a small, battery powered external speaker via the headphone audio jack actually LOST VHF sensitivity to the point a weak, but legible station was totally washed out.

I know there is a lot of discussion of how counterpoise can help the 436HP, but this behavior was kind of opposite of what you might expect. I need to perform the similar test on my 396XT and some of my other older scanners.

I would have expected the opposite of what happened when connecting an external speaker was connected if anything changed at all.

 

[Anderegg]

Thanks for reminding me! I saw a post before about either a mono or stereo headphone shorting out the jack.......can't remember which one will hurt the little guy.

Paul

 

[Anderegg]

OK, the fun has begun. I hang out under the cell phone tower every night.....the emissions keep me warm.

Preliminary trials indicate the HP likes 1/4 stubby and car antennas, but not stock or RS800.....weird. I have access to the ladder, I may climb up to the top to see what type of range the 436 has.

 

[JamesO]

I can tell you my 436HP was much happier around cell towers than 396HP as I used to pick my son up at high school from LAX practice which did not always end on time and my 386XT would go deaf or quiet in the parking lot while my 436HP would continue to work in the same general location. The cell antennas are on the stadium light poles.

Once I was 200-300 yards further away back toward the main street my 396XT would start to work fine again.

BTW, the scanners require either stereo audio connections or stereo to mono adapters. I think all modern Uniden scanners are wired for using stereo audio plugs and using a mono plug will short the output amplifier stage and make it unhappy.

I hope you are kidding about climbing the tower? You are aware of near field RF energy and how the RF field drops off very quickly as you move away from the transmitter antenna?

You might need 2 new scanners after that stunt and your eyeballs and testicles may be like soft boiled eggs. You need your eyeballs to earn a living, not sure about your testicles!

 

[Anderegg]

The base of the ladder has about 1 million warning placards, as well as a notice requiring sunglasses while on the tower..........don't really understand that.

I guess they require stereo plugs because that way the mono audio can go to both left and right of stereo headphones?

Paul