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root <NoEMail@home.org>: Jul 04 01:27PM Four year old Samsung 60" UHD QLED tv cannot be repaired. The problem is lines of dead pixels across screen. Samsung repair center says the display has to be replaced which would cost $1400.   The tv was top-of-the line 3D 240Hz and cost $3300.   Is this representative of Samsung?

captainvideo462009@gmail.com: Jul 03 03:23PM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   Thanks for the interesting write up on 4 channel Jurb. It seems like my receiver, being built around 1974 was at the pinnacle of the 4 channel craze. I never really got involved in 4 channel at the time but it's nice to know that I now have a working remnant of that era. And it really sounds good too. And my profound thanks to Chuck, who as a former Sansui technician really offered some good tips along the way. I couldn't have done this without all your help. Lenny

Chuck <ch@dejanews.net>: Jul 01 01:22PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience the QS quad experience. Chuck

Chuck <ch@dejanews.net>: Jul 02 12:17PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience QS quad . Chuck

Chuck <ch@dejanews.net>: Jul 02 12:18PM -0500 On Sun, 1 Jul 2018 00:17:08 -0700 (PDT), captainvideo462009@gmail.com wrote:     >The guy that I bought the organ donor from included a large plasticized sheet with it showing all possible hookups. It also had brief explanations of all controls and their positions and there seems to be a couple of "synthesized" positions that according to this hookup sheet can apparently simulate 4 channel sound. I think that those look like "hall" and "surround". I do feel like When listening in some of these positions, perhaps I may be imagining it but the sound does seem to take on a whole new spaciousness to it.   >I recall hearing years ago when I first contacted Sansui for a service manual that the 5500 sold for over 900.00 back in it's hey day. In 1974 I was living in a small apartment over a restaurant with my cat. I wouldn't have been able to afford the carton to pack this in.   >So now after all these years I that finally own that has the capability to be used in ways that were not available to me before I don't really know what to expect from it. And so I was wondering if you might be willing to comment on that experience and maybe 4 channel analog in general. Thanks again. Lenny Lenny,   The Sansui surround system was called QS. It wasn't very successful. I noticed a few QS records on EBay including one by a Chicago folk singer Bonnie Koloc on Ovation records. I bought this album in the early 70s and, if you like poppy folk music, it would make an ideal test record to experience the QS quad experience. Chuck

Anonymous <anon@noemail.com>: Jul 04 04:11AM -0500 [RING RING RING]   Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello hello Hello Oh go to Hell   [SLAM]   "Damn, that wore me out"..... "Back to lighting fireworks".........

Jeff Liebermann <jeffl@cruzio.com>: Jul 03 09:43AM -0700 >So obviously the unit is using more power than before and not just a software issue.   >I am thinking it may have a bad mosfet. Cant remove them until I get my hot air station. Does this seem like a reasonable place to start troubleshooting? Maybe the mosfets were damaged from using the power supply to power the unit?   >Thanks in advance for any advice   In the APC SmartUPS, some of these run the switching power supply section full time, whether on AC or battery. On AC, the voltage from the switching section is slightly below the input AC voltage, so the load draws most of its power from the AC line. Of course, they are phase locked. When the AC line voltage disappears, the switching power supply section takes over running the load with zero switching time. I'm not sure if the SU3000 SmartUPS works this way but it's worth checking.   A schematic should be useful: <https://elektrotanya.com/apc_smart-ups_su2200_3000.pdf/download.html> (175K)   Offhand, I would guess(tm) that you blew something up with your 48V power supply. The SU2200/3000RM uses a pile of 4ea 12V 18AH AGM batteries. I believe that they are wired 2 in series and 2 in parallel for a total of 24VDC, not 48VDC. You probably blew up the electronics with the overvoltage.   If it draws lots of current from the battery section, the fets are the likely culprit. However, as I vaguely recall, the SU2200/3000 series has 4 strings of 8 FET's in parallel. It's not going to be much fun finding the one FET out of 32 that is blown. I built a crude current probe using a Hall effect device at the end that is useful for finding which device is sucking the most current.   Most of the value and cost of a UPS are in the batteries. In this case, a set of batteries is about $130 plus shipping. At the local recycler, such large UPS's without batteries are plentiful because the price of a new or refurbished UPS is only a little more than the cost of decent batteries. Incidentally, beware of junk batteries and look at the weight of the battery for a clue as to how much lead is inside. I have my own collection of UPS's with dead batteries.   <https://excessups.ca/refurbished-ups-systems/apc-ups-refurbished/apc-smart-ups-rackmount-refurbished>   Good luck.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

mike <ham789@netzero.net>: Jul 03 12:36PM -0700 On 7/3/2018 9:43 AM, Jeff Liebermann wrote: I built a crude current > probe using a Hall effect device at the end that is useful for finding > which device is sucking the most current.   I've been considering doing that. Can you share details about which parts you used? What kind of sensitivity can you get?   Thanks, mike

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