Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
|
|||
|
|||
Sony KV-27TS29 Power Supply
I bought this nice set from a guy who used to work in an electronics shop.
He obviously gave it a going-over, nothing appears messed up but he did leave three transistors missing: Q601, Q602, and the horizontal output transistor. The first two are located side-by-side on a heatsink, on the primary side of the switching power supply. Testing of the flyback indicates an internal short - probably the original cause of the set's failure. If anyone could tell me the numbers of these transistors (or provide me with a scan of the schematic) I'd be very grateful. Thanks. |
#2
|
|||
|
|||
Hi,
Rono wrote in message ... Q 601, & 602 are 2SC4834, the horizontal output is 2SD4927, This sounds much like a KV32S22 I'm tinkering with ("dead", no picture, no stdby code, etc.) -- though I would have to check the P/N of the HOT to be sure. I believe, replace VDR601-603 also, Sony Sp-Kit, has these Hmmm... I only see *one* VDR in this set ("G" board). What does this "kit" include -- just the 2 chopper Q's plus HOT? How/where can it be purchased? (any idea of cost?) parts but VDR's are seperate! 1.0 ohm fusible is also bad! Solder Yes, I see R607 (0.1ohm) is open. all around the horizontal drive circuitry, replace electrolytic capacitor by the drive transformer, if this unit has one! Rono. Hmmm... several electrolytics in proximity to the HDT. A small 0.47uF in series with the base of the HDrive transistor, perhaps? I suspect I should also check the flyback? Or, is all this just a colossal waste of time (and money!) -- maybe just toss the set? (seems that everyone I know who has owned a Sony TV has had it die in 4 - 6 years) Thanks for any insights! --don "Chris F." wrote in message ... I bought this nice set from a guy who used to work in an electronics shop. He obviously gave it a going-over, nothing appears messed up but he did leave three transistors missing: Q601, Q602, and the horizontal output transistor. The first two are located side-by-side on a heatsink, on the primary side of the switching power supply. Testing of the flyback indicates an internal short - probably the original cause of the set's failure. If anyone could tell me the numbers of these transistors (or provide me with a scan of the schematic) I'd be very grateful. Thanks. |
#3
|
|||
|
|||
I tested the flyback by means of a homemade flyback tester, as described in
the S.E.R FAQ. Flyback produced almost no output at all when connected to the rig. Also, I noticed a faint odor of burnt epoxy (a smell very common to Sony flybacks!), so I'm 99% certain that the flyback is bad at this point. Thanks for the info, if I can get the PS to start up, I might order a flyback and see what happens. Flyback retails for about $40 Cdn.... "Rono" wrote in message ... Don, the kit has 2- 2SC4834, the 2SD4927, & the 0.1 ohm fusible resistor! $ 12.00 approx. Canadian! There may be only one VDR in the unit, but i doubt it! VDR601 # 1-807-288-11, and VDR602 & 603 # 1-810-973-21!! Flyback is likely good! The drive capacitor by the horizontal drive transformer has to be polarized (electrolytic), in order for it needing to be replaced! Sony is definetly worth repair, as long as the CRT is good! The best T.V. around in my opinion! Below is the company I usually get parts from! Good luck, Rono. www.globalsemi.com Ther'e in Mississauga, Ontario 1-800-668-8776 |
#4
|
|||
|
|||
Hi,
Rono wrote in message ... Don, the kit has 2- 2SC4834, the 2SD4927, & the 0.1 ohm fusible My HOT is 2SC5148 (8-729-035-75). Are there different "kits"? resistor! $ 12.00 approx. Canadian! There may be only one VDR in the unit, but i doubt it! VDR601 # 1-807-288-11, and VDR602 & 603 # 1-810-973-21!! I doubled checked the schematic and only one VDR (KV-32S22 G board). Sony P/N 1-610-974-21 at VDR601 Flyback is likely good! The drive capacitor by the horizontal drive transformer has to be polarized (electrolytic), in order for it needing I'm not sure which cap you mean... I have C502 (0.47uF 50V) at the base of the horizontal drive transistor (which drives the horiz drive xformer which drives the HOT). to be replaced! Sony is definetly worth repair, as long as the CRT is good! The best T.V. around in my opinion! What typically *causes* this sort of failure (Q601/602)? I would have assumed the flyback died which would take out the HOT (I still haven't check my HOT) and, eventually, the chopper driving everything (via 601/602) Below is the company I usually get parts from! Good luck, Rono. www.globalsemi.com Ther'e in Mississauga, Ontario 1-800-668-8776 Thanks, I will check them out. --don |
#5
|
|||
|
|||
On Tue, 30 Nov 2004 18:21:45 -0700, "Don" none@given wrote:
Hi, Rono wrote in message ... Don, the kit has 2- 2SC4834, the 2SD4927, & the 0.1 ohm fusible My HOT is 2SC5148 (8-729-035-75). Are there different "kits"? What is your original HOT? Has to be same. resistor! $ 12.00 approx. Canadian! There may be only one VDR in the unit, but i doubt it! VDR601 # 1-807-288-11, and VDR602 & 603 # 1-810-973-21!! I doubled checked the schematic and only one VDR (KV-32S22 G board). Sony P/N 1-610-974-21 at VDR601 Flyback is likely good! The drive capacitor by the horizontal drive transformer has to be polarized (electrolytic), in order for it needing I'm not sure which cap you mean... I have C502 (0.47uF 50V) at the base of the horizontal drive transistor (which drives the horiz drive xformer which drives the HOT). That's true but in Sony, it is very common for bad solder joints in horizontal circuit to blow the horizontal transistor, that includes the horizontal transformer driver because this is part of whole horizontal circuit. to be replaced! Sony is definetly worth repair, as long as the CRT is good! The best T.V. around in my opinion! What typically *causes* this sort of failure (Q601/602)? I would have assumed the flyback died which would take out the HOT (I still haven't check my HOT) and, eventually, the chopper driving everything (via 601/602) Below is the company I usually get parts from! Good luck, Rono. www.globalsemi.com Ther'e in Mississauga, Ontario 1-800-668-8776 Thanks, I will check them out. --don Cheers, Wizard |
#6
|
|||
|
|||
Jason D. wrote in message On Tue, 30 Nov 2004 18:21:45 -0700, "Don" none@given wrote: Rono wrote in message Don, the kit has 2- 2SC4834, the 2SD4927, & the 0.1 ohm fusible My HOT is 2SC5148 (8-729-035-75). Are there different "kits"? What is your original HOT? Has to be same. As I said, 2SC5148 -- per the schematic/parts list (I haven't yet examined the device itself). But, the kit previously mentioned does not appear to use the same HOT (though Q601/602. are 2SC4834M in my parts list and R607 is 0R1 fusible) resistor! $ 12.00 approx. Canadian! There may be only one VDR in the unit, but i doubt it! VDR601 # 1-807-288-11, and VDR602 & 603 # 1-810-973-21!! I doubled checked the schematic and only one VDR (KV-32S22 G board). Sony P/N 1-610-974-21 at VDR601 Flyback is likely good! The drive capacitor by the horizontal drive transformer has to be polarized (electrolytic), in order for it needing I'm not sure which cap you mean... I have C502 (0.47uF 50V) at the base of the horizontal drive transistor (which drives the horiz drive xformer which drives the HOT). That's true but in Sony, it is very common for bad solder joints in horizontal circuit to blow the horizontal transistor, that includes blow the HOT? Or, the horizontal *drive* transistor? the horizontal transformer driver because this is part of whole horizontal circuit. OK. The bad solder joints are a "quality" issue? Or, just fatigue from years of use (temperature cycling, etc.)? to be replaced! Sony is definetly worth repair, as long as the CRT is good! The best T.V. around in my opinion! What typically *causes* this sort of failure (Q601/602)? I would have assumed the flyback died which would take out the HOT (I still haven't check my HOT) and, eventually, the chopper driving everything (via 601/602) Below is the company I usually get parts from! Good luck, Rono. www.globalsemi.com Ther'e in Mississauga, Ontario 1-800-668-8776 Thanks! --don |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
FYI 2SC4834 Sony power supply Q601,Q602 | Electronics Repair | |||
Epson ELP 7200 Projector Power Supply Help | Electronics Repair | |||
Switching Power Supply Failure | Electronics Repair | |||
Identify 2 zenerdiodes on a Sony Playstation 2 power supply | Electronics Repair | |||
Trying to find power supply for external CD burner | Electronics Repair |