SDS200 Hum Reports

[WX4JCW]

I picked up one Friday at Universal, I'm not hearing any hum, now I did have Josh hook it up and when I put the speaker to my ear I heard a noise but under normal conditions, I can't hear anything, what should I look for? no noise coming through the LAN feed or headphones definitely

 

[RRR]

I have one of the very first batches sent out, and I applied the uniden supplied fix item, (following instructions precisely) and DL the firmware to turn the amp off in between transmissions, and mine with from a noticeable hum, to extremely negligible, as in, if I wasn't specifically, intentionally holding the speaker next to my ear, listening for it, I wouldn't even know it was there.

So the fix works, and it was designed specifically for this use, and snapped right into place. And best of all, it was free! (And it also gave me a reason to slide the black metal casing off, to see the scanner is built like a dang tank! )

 

[Anderegg]

Same here RRR...I just aluminum foiled the issue, and went from annoying several feet away hum/buzz, to barely able to hear it if I put my ear 6 inches from my external speaker in a silent room...that is mitigated to beyond the scope of how I will ever monitor the scanner physically. If you are closer than 6 inches from your external speaker, you need mitigation.

Also, $6 3.5mm ground loop isolator eliminated hum/buzz to my PC, even before installing my aluminum foil "fix".

Paul

 

[KI6AOK]

Just received an SDS200 from HRO and it has the hum. I did the foil fix and that reduced it to very tolerable. I’ve ordered the part from Uniden, which I hope will have a better fit and better results.

Laura

 

[m42duster]

Has anyone actually received one with the part installed?

 

[iMONITOR]

So the fix works, and it was designed specifically for this use, and snapped right into place. And best of all, it was free!

You would expect the fix to be designed for something else? The fix should certainly be free. It's to fix a design defect in a $700.00 radio that's still under warranty, and you provided the labor to perform the fix.

 

[m42duster]

True...

I certianly hope the engineer that designed the affected circuit, has been reassigned. Lol

 

[iMONITOR]

I don't understand how a problem like this even got out the door to begin with? Seriously, didn't anyone test them before making them available to the public? Uniden should have mailed out notices to all registered owners advising them of the problem with a no-charge return label for no cost repair and return.

 

[m42duster]

Had to get rid of them somehow.

 

[torishu]

So, I got the NMP200 part from Uniden today and decided to pop my serial #01xx 2nd unit open since I'd already purchased all the protocol upgrades anyway.

To my surprise, the NMP200 part *was* already installed.

So, as I said before... the 01xx unit's hum was louder than my self-repaired 14xx unit, so it was hard for me to tell by ear if the part was installed or I just did a better job of it on my 1st unit. I guess it was the latter.

I re-seated the NMP200 part, applied my copper tape "trick" to beef the part up just a bit to improve conductivity and the 01xx unit is now just about as perfect as it's going to get with this fix, just like my 14xx unit. I can no longer hear the hum over the fan I run on low over in the corner of the room and I'm satisfied.

I haven't enjoyed doing the repairs on the SDS200s, especially the second time, but it's done now and I'm satisfied because my repair was even better than the one coming straight from the shop/factory/whatever.

(Just to update in case anybody was wondering.)

 

[HNguyenLy]

Can someone with a recently purchased quiet unit please upload an audio recording taken from the speaker jack?

After going through Uniden repair twice to resolve the noise issue with no luck, I’ve since sold my unit and am slightly considering taking another shot at the latter by purchasing again. After sending my SDS200 to Uniden repair for the second time, I was sent an exchange unit a month later. This unit looked spanking new with screen protecter and all, but checking the serial number showed me that the unit had a lower number than my original unit. The exchange unit also had the dreaded hum and strangely enough, a repair tech replaced the micro SD card of the exchange unit with my original card, programming and all. Needless to say, I’m not impressed with Uniden repair.

My current thought is that the noise mitigation hack is just that and doesn’t actually illuminate the problem. Following this logic through would seem to indicate that all units have the noise to some degree. Being a blind op with perhaps a higher reliance on my ears, these types of issues bother me more than it might someone else. I would love to be proven wrong regarding the newer batches of the SDS200. Perhaps I should just get another SDS100 and end this quest for the holy grail.

 

[TailGator911]

Might be a hassle for some to dial these radios in, but when you get it right it's a thing of pure beauty. I have been blessed by the fact that neither of my SDS scanners 100/200 have any issues. No hums. No screen flicker. No vhf/uhf deficiencies. No interference or intermod or bleed-over. Nada. I don't even have to use the filters, for the most part. Good right out of the box. I am going to purchase a second SDS200 when I get back to the states in late May. I just love the bright, busy display and how well they decode my local Ohio MARCS Phase 1 digital simulcast system. I take my SDS100 to LA and San Diego area quite often and it performs flawlessly on the other digital systems as well. My heart goes out to all of those who have had problems with these radios. Although I suspect some of those problems are owner-initiated, others are technically legit and it is disheartening to hear their stories. But, on the flip side of that coin, I think Uniden has stepped up regarding the hum issue, and I am glad to hear so many more posting that their SDS200s and 100s are technically sound now and whatever minor issues they have are being resolved via firmware updates and technical repair. My hat is off to Paul Opitz and the Uniden team. Thanks so much for the fantastic radios and keep 'em coming!

JD
kf4anc

 

[allend]

I have done all the fixes on that SDS-200 radio and pretty turned in the towel on it. I just accepted that I spent 700 bucks to hear the noise and this is my second radio. I returned the first one for the same reason.

This is a mickey mouse way but I plug the external speaker into the microphone jack in the front of the radio and turn the volume all the way up. This is how you have to jerry rig it to make no hum noise. I get the hum noise on the internal speaker and the external speaker jack but get no hum noise out the mic jack. This is absolutely GREAT........................................

I pretty much just go back and listen to my BCD996P2 radios since I have never had any issues with those radios. Those radios have never let me down.

I still can't believe after all this time that has passed people are still noticing issues with their radios and no perm fix is in place. Its a hardware issue and design flaw. The only way to fix these radios is do a re-call on all of them and Uniden needs to fix this problem

 

[KR7CQ]

So, I got the NMP200 part from Uniden today and decided to pop my serial #01xx 2nd unit open since I'd already purchased all the protocol upgrades anyway.

To my surprise, the NMP200 part *was* already installed.

So, as I said before... the 01xx unit's hum was louder than my self-repaired 14xx unit, so it was hard for me to tell by ear if the part was installed or I just did a better job of it on my 1st unit. I guess it was the latter.

I re-seated the NMP200 part, applied my copper tape "trick" to beef the part up just a bit to improve conductivity and the 01xx unit is now just about as perfect as it's going to get with this fix, just like my 14xx unit. I can no longer hear the hum over the fan I run on low over in the corner of the room and I'm satisfied.

I haven't enjoyed doing the repairs on the SDS200s, especially the second time, but it's done now and I'm satisfied because my repair was even better than the one coming straight from the shop/factory/whatever.

(Just to update in case anybody was wondering.)

I had little noise to begin with (mostly computer hash with a touch of hum), so though I wasn't in a rush to install the part, I did last week just to have it in, and it quieted it down a bit. Not sure it makes a much difference, but I added a step in my process, and that was using contact cleaner to remove the glue left by the strip that gets removed, before inserting the part. I'm not sure there is enough glue left to make a difference, but I thought it was prudent to do this since it only took a couple of minutes extra and I know there will be the best possible contact this way,

 

[n1chu]

My question has to do with HOW the felt pad strip is removed and further, HOW MUCH of it is removed. I’m guessing just notching out the felt where the new grounding clip is mounted would have people using an exacto knife to remove just that amount of felt stripping to allow a good electrical connection between the copper grounding clip and the metal radio chassis? ...and the use of the exacto knife is frouned upon because it raises the possibility of accidentally slipping off the chassis onto the adjacent circuit board? ... which could damage the circuit board depending upon how much force is applied to the knife?

 

[oldtimeradio]

Has anyone actually received one with the part installed?

Yes, My report is on page 12. last 4 SN-1545
Also bought from HRO but NH. It had some hum and varied if you squeezed the rear of the case, took apart, it had the factory fix but may have been installed by dealer, I made adjustments for a better ground, "fix it my way". Now ZERO HUM.
Thanks for asking.

mike

 

[mikewazowski]

I re-seated the NMP200 part, applied my copper tape "trick" to beef the part up just a bit to improve conductivity and the 01xx unit is now just about as perfect as it's going to get with this fix, just like my 14xx unit. I can no longer hear the hum over the fan I run on low over in the corner of the room and I'm satisfied.

I've done the same. Cleaned the felt strip off, applied a length of thin copper tape along the rail where the felt was and a wider piece along the top of the shield.

I put the shield back and powered the unit back on. You can tell if you've got good contact if the noise is minimal and pressing down on the shield doesn't make much difference.

Put the screws back in while pressing the shield forward and down and the noise is pretty much gone. Haven't even bothered to turn the amp off between transmissions.

 

[torishu]

I've done the same. Cleaned the felt strip off, applied a length of thin copper tape along the rail where the felt was and a wider piece along the top of the shield.

I wouldn't be surprised if something along these lines became part of the official fix. Uniden should consider it, IMO.

The NMP200 part has to be as thin as it is to wedge between the plastic part of the case and the LCD display in the front, but tight contact isn't necessarily maintained against that rail, the NMP200 part, and the lid/shield when the case is put back on. This was evident when the NMP200 part came pre-installed on my second unit and I didn't even know it until opening because of the obvious hum.

The NMP200 part needs to be a little thicker on its exposed surface so that the metal shield/case will press it down and maintain a tight fit. This is what pressing down on it while tightening the screws is supposed to accomplish, but I've found that it wasn't enough. Twice now.

A little copper tape or other conductive material to add that needed thickness on the exposed portion of the NMP200 part after it's wedged in is all it really takes and it's as good as it's going to get with this fix, I believe. My hearing is very good and I find the SDS200 very acceptable noise-wise at this point.

 

[TailGator911]

It is a good idea to always browse this forum for pertinent information before making a purchase of any radio equipment. Most scanners and dealers have been reviewed and discussed here at length, and questions are usually quickly answered. Also, frequent questions pertaining to a specific scanner are usually already answered here in the forums, you just have to search. This website is a very valuable tool for all radio hobbyists.

JD
kf4anc

 

[mule1075]

Just received my SDS 200 sold my 100 to get it. No hum at all out of the box. Ordered mine from Overstock fullfillment by iSave it shipped from South Bend Indiana in case anyone was wondering. I will be playing with it more here in a bit.