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
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
Anyone come across a transistor "D 8050" ? The logo is just a small star.
That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. There is another transistor of the same type on the board, and it reads as a conventional NPN small signal transistor, so shouldn't be a problem to substitute. It would just be nice to know what its ratings are. In case it helps, its in the SMPS of a Wharfedale monitor speaker. It is in the supply circuitry of the controller IC. The PSU is working ok - almost. It had suffered a burn-up around the leg of a cap strapped across the switching transformer somewhere. The resulting carbonised board had tracked across to another print track, and taken that out, along with a zener that was connected to that track. When the burn-up and tracking was all sorted, the PSU came up ok, and all seemed to be well until it was connected to the amplifier. With no signal, you could hear the woofer bumping quite fast. Like quiet motorboating. If you 'scoped the rails, you could see them all 'bouncing' a couple of volts. Turns out that the control IC is starting and stopping in bursts. It looks as though the startup supply is getting the IC going, but the sustain supplsy from the switching transformer is not then taking over. The bad transistor appears to be part of the regulator for this supply. The zener that had blown was connected directly to the base of this transistor, so it all seems to fit. If nobody knows any different, I think I will try an MPSA42 in there. They have a good voltage and current rating, and the right pinout. Arfa |
#2
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
What a bizzarre situation. It looks like it's an American number !
2N8050 : http://www.ebay.com/itm/20pcs-Transi...-/130287351395 Whoda thunkit ? T |
#3
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
On 22.06.2012 02:48, Arfa Daily wrote:
Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. When I see the number 8050 on a TO92 package, my first guess is an S8050: http://www.alldatasheet.com/view.jsp?Searchword=S8050 Best regards Piotr |
#4
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
On Jun 21, 5:48*pm, "Arfa Daily" wrote:
Anyone come across a transistor "D 8050" ? *The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 *D-line plastic package, and the board has its pins marked as E-B-C. I've never seen such a logo and it's driving me crazy. Can you put it on tinypic? I keep thinking it must indicate the transistor is kosher (Dairy): http://www.jewishceliacs.com/jcn%20graphics/Star-d.gif In case it helps, its in the SMPS of a Wharfedale monitor speaker. How old is this? Current production, ten years old, twenty, more? |
#5
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
"Arfa Daily" wrote in message ... Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My Try searching "S8050" - its something along those lines. http://www.alldatasheet.com/datashee...NGS/S8050.html The complement is 8550. They're the power complementary pair sometimes found on the same board as the 9014 series. There's data sheets from various sources on my other PC so if you're still stuck. |
#6
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
"spamtrap1888" wrote in message ... On Jun 21, 5:48 pm, "Arfa Daily" wrote: Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. I've never seen such a logo and it's driving me crazy. Can you put it on tinypic? I keep thinking it must indicate the transistor is kosher (Dairy): http://www.jewishceliacs.com/jcn%20graphics/Star-d.gif In case it helps, its in the SMPS of a Wharfedale monitor speaker. How old is this? Current production, ten years old, twenty, more? Can't say that I'd ever seen it before, either, and I've been in this game a long time. As to the item in question, I believe that it is at least recent if not current. I seem to think that the shop owner that sent it to me for repair, said that the owner had not had it all that long. You should be able to see a picture of the transistor here http://i48.tinypic.com/27wzj85.jpg if I've got the address linking right. Arfa |
#7
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
"Piotr Piatek" wrote in message ... On 22.06.2012 02:48, Arfa Daily wrote: Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. When I see the number 8050 on a TO92 package, my first guess is an S8050: http://www.alldatasheet.com/view.jsp?Searchword=S8050 Best regards Piotr Ah, yes ! Good call. With the "D" in front of the number, I hadn't even considered that it could be an "S" prefix device, but you are right of course. Four digit numbers in the '8000' range often are correctly prefixed by "S". Maybe the "D" is actually part of the logo ?? I've put a piccy on TinyPic - see my reply to spamtrap1888 for the link. Having looked at the S8050 data, it looked a reasonable assumption that that was indeed the type, so I put in a trusty MPSA42, which has the same pinout, similar current rating and better voltage rating, and away it went. Control IC then produced steady and continuous gate drive for the switching FETs, which then produced correct and steady secondary-side voltages, so a good result all round, and Christ knows, I needed one of those for a Friday, after the crap week I've had ... :-) Arfa |
#8
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
On Jun 22, 5:45*pm, "Arfa Daily" wrote:
"spamtrap1888" wrote in message ... On Jun 21, 5:48 pm, "Arfa Daily" wrote: Anyone come across a transistor "D 8050" ? *The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 *D-line plastic package, and the board has its pins marked as E-B-C. I've never seen such a logo and it's driving me crazy. Can you put it on tinypic? I keep thinking it must indicate the transistor is kosher (Dairy): http://www.jewishceliacs.com/jcn%20graphics/Star-d.gif In case it helps, its in the SMPS of a Wharfedale monitor speaker. How old is this? Current production, ten years old, twenty, more? Can't say that I'd ever seen it before, either, and I've been in this game a long time. As to the item in question, I believe that it is at least recent if not current. I seem to think that the shop owner that sent it to me for repair, said that the owner had not had it all that long. You should be able to see a picture of the transistor here http://i48.tinypic.com/27wzj85.jpg if I've got the address linking right. Thank you. The star almost looks like it has a little "i" in its middle. And the two bottom points might be legs. I think the D is placed where it is to make it clear it's not part of the logo, i.e. as far away as possible. (Could it somehow be a date code?) The absence of data books is quite annoying -- who would have thought that the Internet would omit this transistor logo from its collection of dull factoids. |
#9
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
"Arfa Daily" wrote in message ... "Piotr Piatek" wrote in message ... On 22.06.2012 02:48, Arfa Daily wrote: Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. When I see the number 8050 on a TO92 package, my first guess is an S8050: http://www.alldatasheet.com/view.jsp?Searchword=S8050 Best regards Piotr Ah, yes ! Good call. With the "D" in front of the number, I hadn't even considered that it could be an "S" prefix device, but you are right of course. Four digit numbers in the '8000' range often are correctly prefixed by "S". Maybe the "D" is actually part of the logo ?? I've put a piccy on TinyPic - see my reply to spamtrap1888 for the link. A single 'S' prefix is probably the most common, MPS is used by NS & various others and fairchild use 'SS' prefix. |
#10
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
responding to
http://www.electrondepot.com/repair/...ty-140609-.htm , Me, who knows about valves too. wrote: arfa.daily At whites, a MFR of metal detectors 8050's were bought in bulk stuck into an automated tester. A bin lamp lit that you through it into. They were an un-classified very inexpensive if 1 amp+ 200MHz part. Your part had this tested, labeled and is a letter of the alphabet instead of "b" plus a 2 digit number. I have LB's of MPSA 5550's and 5123's with gold leads, having betas over 1100. They made crappy three pole oscillators but great touch pad amps for Moog's. |
#11
Posted to sci.electronics.repair
|
|||
|
|||
Transistor Identity ?
On Friday, June 22, 2012 at 8:55:37 PM UTC-4, Arfa Daily wrote:
"Piotr Piatek" wrote in message ... On 22.06.2012 02:48, Arfa Daily wrote: Anyone come across a transistor "D 8050" ? The logo is just a small star. That is followed by a "D", then below that "8050". My first thought was 2S - D8050, but that turns up no data, except the usual component search engine dead ends and non-existent data sheets. It's a standard TO92 D-line plastic package, and the board has its pins marked as E-B-C. When I see the number 8050 on a TO92 package, my first guess is an S8050: http://www.alldatasheet.com/view.jsp?Searchword=S8050 Best regards Piotr Ah, yes ! Good call. With the "D" in front of the number, I hadn't even considered that it could be an "S" prefix device, but you are right of course. Four digit numbers in the '8000' range often are correctly prefixed by "S". Maybe the "D" is actually part of the logo ?? I've put a piccy on TinyPic - see my reply to spamtrap1888 for the link. Having looked at the S8050 data, it looked a reasonable assumption that that was indeed the type, so I put in a trusty MPSA42, which has the same pinout, similar current rating and better voltage rating, and away it went. Control IC then produced steady and continuous gate drive for the switching FETs, which then produced correct and steady secondary-side voltages, so a good result all round, and Christ knows, I needed one of those for a Friday, after the crap week I've had ... :-) Arfa Except that the S8050 is a PNP and you said that yours checks out as an NPN (and you installed an NPN which works), so any data on that S8050 won't help identifying your part. I'd keep my eye on it a few days before shipping it. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Identity a SOT-23 transistor marked MO5 or M05 | Electronics Repair | |||
CK727 PNP Si drift transistor - CK766 PNP Ge transistor ratings | Electronic Schematics | |||
True identity of PEC? | Metalworking | |||
need a new identity? | Home Repair | |||
Transistor CS1092G in Sutton 8 transistor AM-radio ? | Electronics Repair |