SDS200 Hum Reports

[TailGator911]

Another thing to consider, per the video, is keeping pressure on the front plate while you tighten the screws, as the foil or part could possibly squeeze out of contact (position) during reassembly .

JD
kf4anc

 

[UPMan]

I just added a caption to the video clarifying placement of the foil piece. I realized that if you watch the factory part video, first, you might reasonably assume identical placement for the foil.

 

[tumegpc]

For all of you attempting the foil mod, make sure that it's secure and doesn't come loose. You can easily short out something on the PCB. Especially if you are doing a mobile install. The factory part looks to be a few layers thicker than foil.

 

[epilab]

For all of you attempting the foil mod, make sure that it's secure and doesn't come loose. You can easily short out something on the PCB. Especially if you are doing a mobile install.

Someone asked if you just cut out the location on the adhesive tape where the mod is to be located rather than remove the whole tape it must have been there for a purpose
??

 

[UPMan]

It is just a pad to keep the parts from vibrating against each other. Not an issue when you've got either the part or foil wedged between the top case and the chassis.

 

[tkowalik]

Someone asked if you just cut out the location on the adhesive tape where the mod is to be located rather than remove the whole tape it must have been there for a purpose
??

I suspect that tape was there to prevent possible rattling between the top plate and frame but I removed it and do not have any issues with any type of rattling. It’s very secure and do not see that being an issue.

 

[radio3353]

Upman - Any concern with ESD with having that PCB exposed and the operator not grounded or the work surface not being conductive? Especially given dry air inside homes this time of year. Thanks.

 

[epilab]

It is just a pad to keep the parts from vibrating against each other. Not an issue when you've got either the part or foil wedged between the top case and the chassis.

Thank you. Was not sure if it had any other purpose

 

[SteveSimpkin]

Upman - Any concern with ESD with having that PCB exposed and the operator not grounded or the work surface not being conductive? Especially given dry air inside homes this time of year. Thanks.

I suspect the act of touching the chassis while performing this mod alleviates a lot of potential voltage differences between your body and the circuitry on the radio.

ESD is less of a problem now than it was 30+ years ago. Most CMOS devices now have integral static electricity protection. Also once devices are incorporated into a circuit board they tend to be better protected.

 

[n2pqq]

May we please have an answer to this question

Does this procedure affect the internal speaker , external speaker or both ?

 

[UPMan]

Pretty sure several people have said it affects both. But, I'll chime in, too. It affects both.

 

[trp2525]

When will the updated sds200 units be available to purchase with this already resolved?

...So many interesting questions to be answered that can't be answered now like when will this part actually get to the factory and be installed in the radios being manufactured? Everyone's going to want to know the serial numbers from that point on so they make sure they get that unit when buying it...

FYI the SDS200 webpage at Bearcat Warehouse (Uniden SDS200 Police Scanner | Bearcat Handheld Digital Police Radio) currently states the following as of today (02-23-2019):

"2nd Shipment arriving the first part of March."

"Updated version on the next shipment."

 

[allend]

May we please have an answer to this question

Does this procedure affect the internal speaker , external speaker or both ?

So I followed the exact instructions on how to do the aluminum foil fix for now. It really helped out with the internal speaker but had no effect on the external speaker. Same humming and pulsing noise on any external speaker. Now this is a whole other hardware issue

 

[opiekitty]

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.

Hi UPMan - I used the foil method on mine and it seemed to work. Does this modification have any impact on the units reception? Thank You

 

[mtndog4]

The copper tape folded to the right size works.
( same that was used on the BCD436HP battery door to fix UHF Reception)
i.e https://www.amazon.com/Tapes-Master-10ft-Copper-Foil/dp/B00Z8MCK6M

 

[KenMaltz]

guys: It would seem that the purpose of this part is to provide a more solid ground path from the display to the chassis; thereby reducing the RFI being picked up in the audio chain. If this is indeed the source of the noise, and if the fix is effective, it would also reduce or eliminate the noise in both an external speaker and an earphone. Display noise is often found in both radios and audio equipment and a good ground system often eliminates it.

 

[maus92]

So I followed the exact instructions on how to do the aluminum foil fix for now. It really helped out with the internal speaker but had no effect on the external speaker. Same humming and pulsing noise on any external speaker. Now this is a whole other hardware issue

Post #39 has had variable success when applying a modified interim repair procedure to his 2 SDS200s that use BC20 external speakers. Both had noticeable "noise" 3-4 feet away prior to the mod; now one has barely perceptible "noise" only when listening from 1-2 inches away in a quiet room, and the other from a foot away. Seems that there is variability in manufacture, and the application of the interim mod, particularly since you report no change after the mod when using an external speaker. We need more field reports on the effectiveness of the interim mod procedure when using both the internal speaker and the external speaker jack.

 

[UPMan]

Copper foil tape would be superior to using aluminum foil, as it is much more conductive. If it were commonly in people's houses, that is what we would have demonstrated using. Variability in results is likely due to variability in implementation of the fix. Even a slight increase in conductive contact will have a noticeable difference in results.

 

[m42duster]

Post #39 has had variable success when applying a modified interim repair procedure to his 2 SDS200s that use BC20 external speakers. Both had noticeable "noise" 3-4 feet away prior to the mod; now one has barely perceptible "noise" only when listening from 1-2 inches away in a quiet room, and the other from a foot away. Seems that there is variability in manufacture, and the application of the interim mod, particularly since you report no change after the mod when using an external speaker. We need more field reports on the effectiveness of the interim mod procedure when using both the internal speaker and the external speaker jack.

Sounds like we have similar results.

 

[RCjim]

The foil is NOT the permanent fix. UPMan's working on it. Read acove

Would have been great to hear what the unit sounded like before and after the mod. just my 2 cents.