SDS200 SDS200 Hum Reports

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KR7CQ

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I want to know if this is going to fix the external speaker issue?
A good question. My hunch is that it will. I believe there is a grounding issue allowing computer noise to bleed into the audio circuit, and that if that is fixed the problem should be solved with the internal speaker as well as with external speakers. UPman?

Still, I would also feel pretty nervous with my return period running out. I am struck by the fact that some units display no noise, while some have "some" noise (like mine), and that some others have an unacceptable amount of noise. Based on what m42duster is saying, I would be wondering if my "unacceptable noise" unit will be acceptable after the mod....tough decision to make there.
 

tkowalik

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This is my feed. This is post temporary foil mod. Rear speaker output.

http://www.broadcastify.com/listen/feed/30015
I hear it but I have to turn my speaker up all the way which makes the audio traffic way too loud. If I put the speaker at a reasonable level for actual traffic, I can’t hear it unless I’m right up against the speaker.

In other words, I don’t find it annoying enough not to listen.
 

m42duster

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I hear it but I have to turn my speaker up all the way which makes the audio traffic way too loud. If I put the speaker at a reasonable level for actual traffic, I can’t hear it unless I’m right up against the speaker.

In other words, I don’t find it annoying enough not to listen.
If you were sitting where I'm at, you'd likely change your mind. It's why I have it outside of my shack providing a feed. My TRX-2 is on my bench.
 

torishu

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Still, I would also feel pretty nervous with my return period running out. I am struck by the fact that some units display no noise, while some have "some" noise (like mine), and that some others have an unacceptable amount of noise. Based on what m42duster is saying, I would be wondering if my "unacceptable noise" unit will be acceptable after the mod....tough decision to make there.
That's exactly my concern. There are units with hum, units without hum. Let's say the factory fix + firmware reduces noise by 70%... if the hum on individual units is variable, as it seems to be, then so will be the resulting outcome. So one person has the hum barely there but the next person has hum a little louder, the next person louder than that, and so-on.

A 20% cut, even a 50% cut, isn't going to work in my case and I wish I knew more as my return window was coming to a close. I'm going to be more than a little upset if it closes and the fix results in only a slight reduction in noise for me and the next person's is far quieter after the fix.

Will there be a narrow baseline that all units will fall into after the fix or will it be a wide variability as it seems to be now?

I know, people will yell at me to just return it then and sneer. I may. I really do love the SDS200, though. Aside from the hum it's a great-looking, even great-sounding unit. If I could get a mostly hum-free version or was guaranteed such a unit in the near future if the fix is unacceptable, I would be satisfied. I want this scanner. For the price, I feel a little bit of agonizing over this flaw is acceptable. I apologize to those who disagree.
 
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tkowalik

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If you were sitting where I'm at, you'd likely change your mind. It's why I have it outside of my shack providing a feed. My TRX-2 is on my bench.
Interesting. One thing you might try, and it is risky, is power up the unit and move that top cover toward the screen more and put slight pressure on it. Note if it gets louder or quieter.

Keep in mind it is very easy to make contact with that top plate to components on the board and if you’re not careful you can short something out pretty easily.
 

m42duster

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I understand your concern. I have a short return window as well. I only wish I had the factory part to slap in and do a comparison. I double checked the foil placement, but again, I see little difference. I will wait further.....
 

torishu

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I hear the sound of a computer booting up through my external speaker as it loads up and I actually get a chuckle out of that, but the computer-related noise during scanning is pretty modest so I guess I got lucky this time after bad luck with the SDS100
Thank you.

Yeah, I can live with a little CPU hash noise. It's the constant hum that I need to have addressed. In a quiet room it's too much. And I'm somebody who runs a fan 24/7 for the slight white noise (and a modest breeze to avoid stale air; and, yes, it was all shut down to make sure the hum isn't due to interference. Multiple rooms, outlets, even tried it at multiple locations).

I will check out Bearcat Warehouse -- thanks for the recommendation. I got mine through Scanner Master and I believe them to be reasonable (I've never had to return anything). It's simply that my 30 days is fast-approaching.

I'll keep it if it sounds like there will be a narrow baseline from unit-to-unit. If it's going to a wide baseline, then I already know my unit will be on the upper fringes.
 

Stecomp

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Uniden Repair has had my 200 for exactly 2 weeks for the hum issue and I was half jokingly looking at the serial number on the video unit for a match. I was assuming mine was one of the first to be returned but if its as widespread as it seems, they probably didn't have to look to far to find one in the warehouse. Curious if mine will be fixed with the shown part now or if that was a one off engineering design and will have to wait for a few more weeks for the supply to come in.
 

maus92

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That's exactly my concern. There are units with hum, units without hum. Let's say the factory fix + firmware reduces noise by 70%... if the hum on individual units is variable, as it seems to be, then so will be the resulting outcome. So one person has the hum barely there but the next person has hum a little louder, the next person louder than that, and so-on.

A 20% cut, even a 50% cut, isn't going to work in my case and I wish I knew more as my return window was coming to a close. I'm going to be more than a little upset if it closes and the fix results in only a slight reduction in noise for me and the next person's is far quieter after the fix.

Will there be a narrow baseline that all units will fall into after the fix or will it be a wide variability as it seems to be now?

I know, people will yell at me to just return it then and sneer. I may. I really do love the SDS200, though. Aside from the hum it's a great-looking, even great-sounding unit. If I could get a mostly hum-free version or was guaranteed such a unit in the near future if the fix is unacceptable, I would be satisfied. I want this scanner. For the price, I feel a little bit of agonizing over this flaw is acceptable. I apologize to those who disagree.
If I were you, I’d return the unit and await a verified solution. You seem to be concerned about a closing return window, and it is unclear when a complete / satisfactory solution can be applied to the affected radios. In my case, I can wait because the noise is not affecting my use case.
 

mrhermit

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Any idea what the sticky strip that was removed is and should it be replaced to furfill it’s original purpose
Why not just cut away the center portion of the foam piece to install the fix? I don't understand why the whole foam strip has to be removed. It must have served some purpose or Uniden would not have installed it in the first place.
 

SteveSimpkin

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Why not just cut away the center portion of the foam piece to install the fix? I don't understand why the whole foam strip has to be removed. It must have served some purpose or Uniden would not have installed it in the first place.
From looking at the video it looks like this EMI gasket-like part is used to ground the metal frame of the display assembly to the chassis using the slight gap between the chassis and the top shield cover. The foam strip may have prevented the top cover from making a tight contact with this piece.
 

SteveSimpkin

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I would think that the factory fix is going to be more permanent by soldering a ground to the LCD frame.
Maybe, maybe not. This "fix" is probably easier to insert into the current production line than anything involving soldering. Perhaps in a future revision they could make changes to the board or sheet metal or assembly process to better shield or ground the display assembly.

I also wonder if they will direct their distributors/dealers to test the SDS200's they have in stock and apply this modification to units that exhibit the noise issue.
 

markjrenna

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So does this piece of metal with foil (NMP200) resolve ALL ISSUES as in the HUM and the CPU BUZZ from the speaker underneath, the ear phone jack, and an attached external speaker?

And I don't expect to hear from the Uniden shill as he calls it a phenomenon. No, you should call it what it is. An error in design. But you need to side step an wiggle. The truth is very hard for you to admit. I get it. So you don't get my 700.
 

maus92

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So does this piece of metal with foil (NMP200) resolve ALL ISSUES as in the HUM and the CPU BUZZ from the speaker underneath, the ear phone jack, and an attached external speaker?

And I don't expect to hear from the Uniden shill as he calls it a phenomenon. No, you should call it what it is. An error in design. But you need to side step an wiggle. The truth is very hard for you to admit. I get it. So you don't get my 700.
My earphone jack does not have any problems when monitoring with professional (studio) headphones, however the internal speaker or an external speaker connected to the ext spkr jack does. The shield part install procedure is a partial solution to the "noise" issue as was stated by the product manager. There is a future firmware release that is being developed to address other aspects of the "noise." Will it work? We don't know yet since the factory part and firmware have not been released - thus field reports are unavailable. I would expect that the interim aluminum foil procedure only partially addresses the issue, as one should expect.
 

escortz28

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I have two SDS200s, each had the hum/digital noise out-of-the-box. I was able to get both acceptable to me. I had performed two modifications on each - Scotch Copper Tape (performs the same function as Uniden's aluminum foil but better conductivity and adhesion) and the double sided tape (https://forums.radioreference.com/threads/simple-solution-verified-for-sds-200-speaker-noise-issue.383622/). With the Scotch Copper Tape I contacted as much surface area as I could between the display metal frame and the metal chassis.

Results - One SDS200 the noise is barely perceptible within an inch or two of the external speaker in a quiet room. Second SDS200 the noise is perceptible within a foot or so of the external speaker in a quiet room, especially when loading the full database. Prior to mods, both units could be heard at 3-to-4 feet from the external speaker to my listening position (not under quiet conditions). Both units use the same model external speaker (BC20) and same model of microSDHC 32GB memory card (Samsung Evo Select).

I am anxiously awaiting the firmware update. I really would like to spend my time listening to the 200s vs. modifying them.
 

UPMan

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Just did the foil mod. If I had to guess, I'd say it suppressed the noise by 20%.

Maybe a tad more, but not much.
I'd suspect the foil is not positioned well. Note that it goes to the left (viewing from the back) of where the factory part will go. It must wedge between the LCD shield and the cabinet to make adequate contact. Noise reduction should be more like 90% (as others have reported).

To others, note that a shill is someone who is paid by a company to provide positive or misleading information and who hides their affiliation with that company. We don't pay for positive reviews, and my position at Uniden (Director of Product Development) is no secret.
 

tkowalik

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I'd suspect the foil is not positioned well. Note that it goes to the left (viewing from the back) of where the factory part will go. It must wedge between the LCD shield and the cabinet to make adequate contact. Noise reduction should be more like 90% (as others have reported).
100% agree. One thing I guess I never mentioned is positioning is very important.
 
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