BCD436HP/BCD536HP: UHF Reception Issues due to Noise from Battery Compartment

[troymail]

UHF/VHF picked up good with the tape on in the area I was staying at. I was hoping the 800 system would have been better in the area I was at. But I was picking up a 800 system with 1 bar that was 50 miles away.

50 miles! -- must be a pretty old analog system... any reception of that with "stock" materials (radio, antenna, etc.) is probably as good as it will get.

I would consider the 436 to be superior on 800 mhz. I would expect you were just too far away from the system. UHF has been the area of poor performance, but we all know that can be fixed with some shielding.

I agree almost 100% - the one word I'd change is "fixed" in this - it can be improved with some shielding but a "fix" would have to come from Uniden but my guess is they'll never acknowledge there is a problem. This line (BCDx36HP) and it's recall/repair issues have almost certainly already cost Uniden a ton of money.

 

[bearcat]

50 miles! -- must be a pretty old analog system... any reception of that with "stock" materials (radio, antenna, etc.) is probably as good as it will get.



I agree almost 100% - the one word I'd change is "fixed" in this - it can be improved with some shielding but a "fix" would have to come from Uniden but my guess is they'll never acknowledge there is a problem. This line (BCDx36HP) and it's recall/repair issues have almost certainly already cost Uniden a ton of money.

I concur. Poor choice of words. I agree we are one month into these findings and nothing from Uniden. Keep in mind long before I found this issue many had complained about the UHF being poor and nothing happened there either. So in the long run the shielded battery door my be our only remedy. Even if it is a band-aid approach.

 

[bravo14]

50 miles! -- must be a pretty old analog system... any reception of that with "stock" materials (radio, antenna, etc.) is probably as good as it will get.

Yes it is a old analog 800 system. They're slowly upgrading to p25 on that system.

 

[troymail]

I concur. Poor choice of words. I agree we are one month into these findings and nothing from Uniden. Keep in mind long before I found this issue many had complained about the UHF being poor and nothing happened there either. So in the long run the shielded battery door my be our only remedy. Even if it is a band-aid approach.

...and as at least one other user stated previously -- "$500+ radio and we have to put tape on it to make it work???" Sad.

 

[troymail]

Yes it is a old analog 800 system. They're slowly upgrading to p25 on that system.

When they switch, you'll see the number of complaints and requests for help posted here somewhere....

 

[k3fs]

I concur. Poor choice of words. I agree we are one month into these findings and nothing from Uniden. Keep in mind long before I found this issue many had complained about the UHF being poor and nothing happened there either. So in the long run the shielded battery door my be our only remedy. Even if it is a band-aid approach.

When there is a problem, admit it as soon as possible.

Customers are not stupid. Ignoring or denying a legitimate problem is not the way to handle it.

HMMMMMM. I guess it's not a legitimate problem.

 

[bearcat]

When there is a problem, admit it as soon as possible.

Customers are not stupid. Ignoring or denying a legitimate problem is not the way to handle it.

HMMMMMM. I guess it's not a legitimate problem.

Well we have been told in no certain terms by many that there is no problem. I think the facts prove there is a problem, but if you do not consider anything a problem then those words would never apply anyway.

 

[jdolina]

I had a chance today to take my 436hp on the road to work (stock antenna) for an event in town I was looking to monitor during the day. I thought it would be a good exercise to program in some of the more active DMR systems in the area. I also have a sdrsharp dsd setup with a $7.00 DVB-T+DAB+FM+SDR usb stick with the stock antenna that comes with the TV tuner. Even with 3 layers of copper on the battery door I am getting hardly any traffic out of a cap+ system (2 hits all day) that has constant chatter and zero traffic on a conventional one frequency DMR channel. Both of these systems are being picked up just fine and active with the USB sticks stock antenna. This is very disappointing.

 

[k3fs]

It may take a couple more layers of copper tape.

Seems like a legitimate problem to me.

 

[bearcat]

436 UHF Noise Issue Update

At this point it appears that Uniden is going to stay in denial that this issue exists. I would have thought by now that they would have at least acknowledged it. I do not think they ever will. They may consider it just a bunch of hogwash. I know that it is effective. Some how this thread got to 26 pages over 500 comments! Not bad for an issue that does not exist in the eyes of the manufacturer.

I was gifted some mesh shielding tape. So I can now report on every option that we have tried. Each of them seems to offer some degree of improvement. At my location I have come to the following conclusions.

Best - A battery door sprayed with 10 coats of EMI/RF nickel spray, and a piece of aluminum shielding tape over the the foam.

Good - Aluminum tape going over the foam, two layers.

Fair - Copper/Mesh Tape going over the foam.

I am more than disappointed at the lack of response from Uniden, but that is out of my control so I will just forge ahead. At least I know have a radio that performs as it should.

Can anyone else offer their experiences with the shielding?

 

[mancow]

I have been working on rebuilding old Thales Racal 25 packs. This is a shorty pack but the regular sized ones are similar in that they all have copper tape around the batteries that makes contact with a ground lug. It appears they were onto the same issue.

 

[IAmSixNine]

At this point it appears that Uniden is going to stay in denial that this issue exists. I would have thought by now that they would have at least acknowledged it. I do not think they ever will. They may consider it just a bunch of hogwash. I know that it is effective. Some how this thread got to 26 pages over 500 comments! Not bad for an issue that does not exist in the eyes of the manufacturer.
I am more than disappointed at the lack of response from Uniden, but that is out of my control so I will just forge ahead. At least I know have a radio that performs as it should.

Can anyone else offer their experiences with the shielding?

Should Uniden comment on an issue that may only affect a small number of handsets. They have manufactured these units for several years. Im guessing they may have had small revisions as time has passed. Maybe even sourced materials from different vendors over the years. Did a small batch have an issue, im sure they did. So while im not dis agreeing with you that your unit and several / many others may have an issue, is it really necessary for Uniden to hop on here and announce the units have an issue. NO. You have done plenty of that for them. There is not a problem with the product line theres an issue with a small batch more then likely.

IF your so unhappy with this issue sell the darn thing and move on.
Its great that some time was spent to find a band aid type solution to the issue for the small or large number of units affected but it doesnt appear to be a wide spread issue. Thats probably why uniden has not responded.

To answer your question, my experience with the shielding yielded negative results. I tried with 1 layer and maxed out at 4 or 5 layers. I tested with a distant UHF DMR channel and my unit decoded / rx better with out copper tape shielding. But hey thats just my unit.

 

[bearcat]

Should Uniden comment on an issue that may only affect a small number of handsets. They have manufactured these units for several years. Im guessing they may have had small revisions as time has passed. Maybe even sourced materials from different vendors over the years. Did a small batch have an issue, im sure they did. So while im not dis agreeing with you that your unit and several / many others may have an issue, is it really necessary for Uniden to hop on here and announce the units have an issue. NO. You have done plenty of that for them. There is not a problem with the product line theres an issue with a small batch more then likely.

IF your so unhappy with this issue sell the darn thing and move on.
Its great that some time was spent to find a band aid type solution to the issue for the small or large number of units affected but it doesnt appear to be a wide spread issue. Thats probably why uniden has not responded.

To answer your question, my experience with the shielding yielded negative results. I tried with 1 layer and maxed out at 4 or 5 layers. I tested with a distant UHF DMR channel and my unit decoded / rx better with out copper tape shielding. But hey thats just my unit.

Well the only flaw in your 'batch' theory is that the problem exists on units from 2013, 2014, 2015 and 2016. So it is not a small sample size, nor is it a problem that has been corrected. I never had the clock issue, but never told those who did to sell it and move on. I am happy they fixed that for those who had the problem. There is no need to sell it now. It works great. Beside I would be hard press to take someones money knowing that I sold them a problem. Honesty is important to me. I will say that in the future I will be very cautious when purchasing further Uniden products. At least until I see if they move forward with their promises. I will also do a much better job of evaluating the performance of the product right out of the box. I am very pleased that you have a good unit. You should feel blessed.

 

[RFI-EMI-GUY]

I have been working on rebuilding old Thales Racal 25 packs. This is a shorty pack but the regular sized ones are similar in that they all have copper tape around the batteries that makes contact with a ground lug. It appears they were onto the same issue.

That also improves the antenna counterpoise and the radiation efficiency of the portable. Good to take note.

 

[k3fs]

It is an issue the product line. We had a meeting of several local 436 users. Every radio showed the issue to some extent. Radios ranged from the very early production models to some very recent production models with the new LEDs.

When there is a problem, admit it as soon as possible.

Customers are not stupid. Ignoring or denying a legitimate problem is not the way to handle it.

Not my words. A radio that receives poorly is a problem. Not delivering features you have announced is a problem.

 

[SCPD]

I have a recent run 436 and it has great reception to over zealous reception. While I can live with the great reception I wonder if it'll come to ehat many others have encountered with poor band reception in uhf or others. So far luckily good.

 

[bearcat]

I have a recent run 436 and it has great reception to over zealous reception. While I can live with the great reception I wonder if it'll come to ehat many others have encountered with poor band reception in uhf or others. So far luckily good.

The only way to truly know if you have the issue is to measure the noise at the negative side of the middle battery. The noise may be there and my guess it is. You may have no trouble hearing what you want to hear. Just today I found a DMR repeater that is probably about 60 - 70 miles away. That comes in perfect with the shielded battery door. Once I remove the door. Zero. Not even a hint of a signal. That is with the stock antenna, not an external antenna. Since you are new to the thread this noise does not cause any problem if you are using an external antenna. Once the antenna is moved away from the noise source the issue goes away. If I am wrong I am glad you got a good one.

 

[SCPD]

Nope don't have the issue and picking up signals a good ways away. This is why I held off so long before buying nkt to long ago.

 

[bearcat]

Nope don't have the issue and picking up signals a good ways away. This is why I held off so long before buying nkt to long ago.

Did you see any noise on the middle battery when you measured it or just a very low amount? I only have an SDR at my disposal for testing. Just curious did you happen to have a full blown spectrum analyzer? I would like to get mine on a top shelve SA someday.

 

[troymail]

Well - this is interesting.... proves (as we all know) that sometimes there are design and manufacturing problems:

http://forums.radioreference.com/unication-forum/339805-unication-g4-g5-audio-dropout.html

But it also shows that some vendors are quick to admit they have a problem.....