When the audio issue was identified with the 536HPs, and Uniden offered the radio swap for those with the problem, does anyone actually know what was changed after Uniden supposedly fixed the problem?
I know that Uniden called it a "misplaced" component or another words, a component that was not soldered to the correct pads on the board or perhaps an electrolytic cap or diode installed in reverse.
I guess they officially called this the "Headphone Campaign".
I'm looking for info as to what component was actually changed or placed correctly.
I had my 536HP open the other day and added a REAR port duplicate of the Front USB programming port.
You can't just solder your wires to the front panel board that is well labeled as there are inductors and maybe a cap or two between where the board in marked and where the traces actually run to the front USB port.
I first tried selecting an inductor for the data and power lines that the Uniden front panel board has on it but I don't have the specs or value(s) of what value inductor they may have used.
Actually, one of the inductors is a dual inductor that handles BOTH of the USB port data lines then there is an inductor installed on the B+ line.
I don't have a way of measuring inductor values plus these parts are some of the smallest SMD type devices made so would be hard to remove without damage to the part or the board. Removing the inductors would be the only way to get an accurate measurement of its value though.
So, after I had my new rear jack installed and my guess value inductors installed, I gave it a try. The 536HP did detect I'd jacked in a live USB wire and asked me for mass storage or serial port mode.
So far so good until I actually used my new connection to transfer data. Then things went bad and I had card corruption or LOTS of corrected data as indicated by Win 7's event log.
So I had to go back to using the front port which I hate as I can't use the controls with the cable plugged into the front port. I am more afraid of breaking off the cable plug or damaging the actual female port part of the jack which is a scanner component that would be hard to replace by the end user.
I never did try and guess other inductor values that should work and basically abandonded the idea until I had more time to look at this again and start over.
So on my 2nd attempt, I ended up cleaning up the tiny board traces between the built in jack and the board mounted inductors and made my tap at that point. This worked fantastic and I've not had a single data error when using my new rear mounted front USB port jack.
In fact, I know leave a cable attached always on my new jack and only need to hook it too a USB cable extension that is plugged into a USB 3.0 port on the rear of my desktop.
The 536HP knows when you hook the cables together as it senses the presence of +5 volts on the USB ports B+ line. My next project is a box that will have a tiny switch I can flip that will signal the 536HP that I have connected the USB port and am ready to make my choice of Mass Storage or Serial Port mode. All I need to do is supply +5 VDC to the USB ports B+ line. When done, I switch my switch off and the 536 goes back to normal operation as it thinks you have unplugged the USB cable.
No ill effects by leaving the ground and the two USB data lines connected. Only the +5 volt signal needs to be supplied to make the 536 know you are ready to talk with it in Mass Storage or Serial mode.
The +5 VDC signal into the 536HP comes from the external source which is what triggers the x36HP model into knowing you have attached a cable.
Anyway, while re-working my new rear mounted USB interface, I had to remove more of the 536HP front panel to actually remove the board that has the SD card slot as well as the USB port so I could attach my new port correctly.
While I had all this apart, I did notice a larger SMD type ceramic capacitor had been removed and one end now soldered to another SMD type ceramic cap on the board which is also the headphone out section of the circuit.
There was also a now unused solder pad where the SMD cap used to be soldered. The cap that was moved was still attached to its original solder pad on one end but was now soldered more at an angle so the other end could be soldered to the top of a similar sized ceramic SMD cap that was not moved from its original pads. Now it is possible that the values of one or both of these caps in the headphone circuit changed from the original value but it did not look like the board or the one cap had been reworked or replaced. Only the one that was now soldered to the top of another cap appeared to have been re-worked as you could see the difference in the solder on both ends.
So I guess my main question is if anyone knows the values of these two caps in the headphone out stage and if that value was changed after Uniden re-worked the bad units?
I also wonder if anyone has attempted to draw a schematic of the headphone output stage? I was going to do that but forgot and had mine all back together before I realized I was going to try and draw the circuit on paper. I'd love to see one that has the audio headphone problem and was never sent in for repair as I would take mine back apart and draw the circuit on paper so anyone can see what they changed.
I also wonder if the newer models with higher serial numbers possibly have a redesigned circuit board as the original problem units obviously had a circuit trace error on those original boards in the early or low serial number models. I doubt Uniden would have designed a board where he solder pads for one capacitor could not be used and the capacitor had to be instead, soldered on top of another capacitor!
I know this is a common fix, when possible, for production units where an error is discovered after several units are now in the hands of the end user but usually a board revision is made and a new board is installed that can have correctly soldered components placed on it.
The way Uniden's original board was re-worked would have prevented the board from being machine populated and wave soldered.
I guess they could have and just left out the one misplaced capacitor and then sent the boards back through a human staffed repair line where a human could solder in the correct capacitor at the oddball angle needed to get it all soldered up correctly. I doubt a machine could have been used to re-work the misplaced component boards that Uniden fixed.
Anyway, it would be nice to know the values and correct orientation of the components in the headphone output stage of the 536HP's for those that have been repaired and maybe a drawing of how the circuit was actually setup when the early models were produced but they were setup incorrectly.
I have a 536 that may never go in for repair and I don't even know if it has the headphone problem but knowing how things should be would be nice for those that would rather fix them themselves.
I myself am not worried about warranty issues as I've long ago voided my warranty by the customizations I've made since darn near day 1!
I have another that claims to have had the audio issue fixed but it has not plus it never had the 3 year warranty sticker applied so the reseller probably just grabbed another unit off their shelves and sent me that not knowing Uniden was actually recalling existing stock from the resellers or fixing the units already in the publics hands.
I asked this reseller if they were sure the audio problem had been fixed in the new unit they were sending me but they acted like they knew nothing about the problem.
That's very possible as Paul had just announced they were working on a way for those already in use to send them in for repair and that they were notifying and pulling inventory from their vendors that had stock of the defective units. I sent my unit back to my vendor within a day or two of Paul announcing the headphone campaign for another problem and asked that vendor to confirm the replacement unit had the headphone issue repaired on the new unit they were sending me.
They acted like I was crazy and did not seem to even know about the headphone issue even though Paul had stated that all defective units in vendors inventory had been recalled and they should be getting a new shipment of repaired units in the next day or so. Mine was shipped to me maybe a day before the vendors should have had their repaired units in stock so I suspect mine was never repaired as it does have static in the headphone output but I let it go as I never use it anyway.
Thanks for any positive info on any accurate info anyone may know concerning this problem!
I really wish Uniden would release a section of the schematic showing the incorrect and correct headphone circuit component placement and wiring.
I'd take my others apart and compare but getting that board out is not a super simple matter and takes some time.
I know that Uniden called it a "misplaced" component or another words, a component that was not soldered to the correct pads on the board or perhaps an electrolytic cap or diode installed in reverse.
I guess they officially called this the "Headphone Campaign".
I'm looking for info as to what component was actually changed or placed correctly.
I had my 536HP open the other day and added a REAR port duplicate of the Front USB programming port.
You can't just solder your wires to the front panel board that is well labeled as there are inductors and maybe a cap or two between where the board in marked and where the traces actually run to the front USB port.
I first tried selecting an inductor for the data and power lines that the Uniden front panel board has on it but I don't have the specs or value(s) of what value inductor they may have used.
Actually, one of the inductors is a dual inductor that handles BOTH of the USB port data lines then there is an inductor installed on the B+ line.
I don't have a way of measuring inductor values plus these parts are some of the smallest SMD type devices made so would be hard to remove without damage to the part or the board. Removing the inductors would be the only way to get an accurate measurement of its value though.
So, after I had my new rear jack installed and my guess value inductors installed, I gave it a try. The 536HP did detect I'd jacked in a live USB wire and asked me for mass storage or serial port mode.
So far so good until I actually used my new connection to transfer data. Then things went bad and I had card corruption or LOTS of corrected data as indicated by Win 7's event log.
So I had to go back to using the front port which I hate as I can't use the controls with the cable plugged into the front port. I am more afraid of breaking off the cable plug or damaging the actual female port part of the jack which is a scanner component that would be hard to replace by the end user.
I never did try and guess other inductor values that should work and basically abandonded the idea until I had more time to look at this again and start over.
So on my 2nd attempt, I ended up cleaning up the tiny board traces between the built in jack and the board mounted inductors and made my tap at that point. This worked fantastic and I've not had a single data error when using my new rear mounted front USB port jack.
In fact, I know leave a cable attached always on my new jack and only need to hook it too a USB cable extension that is plugged into a USB 3.0 port on the rear of my desktop.
The 536HP knows when you hook the cables together as it senses the presence of +5 volts on the USB ports B+ line. My next project is a box that will have a tiny switch I can flip that will signal the 536HP that I have connected the USB port and am ready to make my choice of Mass Storage or Serial Port mode. All I need to do is supply +5 VDC to the USB ports B+ line. When done, I switch my switch off and the 536 goes back to normal operation as it thinks you have unplugged the USB cable.
No ill effects by leaving the ground and the two USB data lines connected. Only the +5 volt signal needs to be supplied to make the 536 know you are ready to talk with it in Mass Storage or Serial mode.
The +5 VDC signal into the 536HP comes from the external source which is what triggers the x36HP model into knowing you have attached a cable.
Anyway, while re-working my new rear mounted USB interface, I had to remove more of the 536HP front panel to actually remove the board that has the SD card slot as well as the USB port so I could attach my new port correctly.
While I had all this apart, I did notice a larger SMD type ceramic capacitor had been removed and one end now soldered to another SMD type ceramic cap on the board which is also the headphone out section of the circuit.
There was also a now unused solder pad where the SMD cap used to be soldered. The cap that was moved was still attached to its original solder pad on one end but was now soldered more at an angle so the other end could be soldered to the top of a similar sized ceramic SMD cap that was not moved from its original pads. Now it is possible that the values of one or both of these caps in the headphone circuit changed from the original value but it did not look like the board or the one cap had been reworked or replaced. Only the one that was now soldered to the top of another cap appeared to have been re-worked as you could see the difference in the solder on both ends.
So I guess my main question is if anyone knows the values of these two caps in the headphone out stage and if that value was changed after Uniden re-worked the bad units?
I also wonder if anyone has attempted to draw a schematic of the headphone output stage? I was going to do that but forgot and had mine all back together before I realized I was going to try and draw the circuit on paper. I'd love to see one that has the audio headphone problem and was never sent in for repair as I would take mine back apart and draw the circuit on paper so anyone can see what they changed.
I also wonder if the newer models with higher serial numbers possibly have a redesigned circuit board as the original problem units obviously had a circuit trace error on those original boards in the early or low serial number models. I doubt Uniden would have designed a board where he solder pads for one capacitor could not be used and the capacitor had to be instead, soldered on top of another capacitor!
I know this is a common fix, when possible, for production units where an error is discovered after several units are now in the hands of the end user but usually a board revision is made and a new board is installed that can have correctly soldered components placed on it.
The way Uniden's original board was re-worked would have prevented the board from being machine populated and wave soldered.
I guess they could have and just left out the one misplaced capacitor and then sent the boards back through a human staffed repair line where a human could solder in the correct capacitor at the oddball angle needed to get it all soldered up correctly. I doubt a machine could have been used to re-work the misplaced component boards that Uniden fixed.
Anyway, it would be nice to know the values and correct orientation of the components in the headphone output stage of the 536HP's for those that have been repaired and maybe a drawing of how the circuit was actually setup when the early models were produced but they were setup incorrectly.
I have a 536 that may never go in for repair and I don't even know if it has the headphone problem but knowing how things should be would be nice for those that would rather fix them themselves.
I myself am not worried about warranty issues as I've long ago voided my warranty by the customizations I've made since darn near day 1!
I have another that claims to have had the audio issue fixed but it has not plus it never had the 3 year warranty sticker applied so the reseller probably just grabbed another unit off their shelves and sent me that not knowing Uniden was actually recalling existing stock from the resellers or fixing the units already in the publics hands.
I asked this reseller if they were sure the audio problem had been fixed in the new unit they were sending me but they acted like they knew nothing about the problem.
That's very possible as Paul had just announced they were working on a way for those already in use to send them in for repair and that they were notifying and pulling inventory from their vendors that had stock of the defective units. I sent my unit back to my vendor within a day or two of Paul announcing the headphone campaign for another problem and asked that vendor to confirm the replacement unit had the headphone issue repaired on the new unit they were sending me.
They acted like I was crazy and did not seem to even know about the headphone issue even though Paul had stated that all defective units in vendors inventory had been recalled and they should be getting a new shipment of repaired units in the next day or so. Mine was shipped to me maybe a day before the vendors should have had their repaired units in stock so I suspect mine was never repaired as it does have static in the headphone output but I let it go as I never use it anyway.
Thanks for any positive info on any accurate info anyone may know concerning this problem!
I really wish Uniden would release a section of the schematic showing the incorrect and correct headphone circuit component placement and wiring.
I'd take my others apart and compare but getting that board out is not a super simple matter and takes some time.
