Those are DEFINITELY fakes. My 9539 date coded devices were bought as NOS from a local surplus dealer, who suspected they could be fakes. We were both pleasantly surprised to find out they were good (along with the batch of MJL1302's). Obviously, they were making both of those series in the mid-90's before the ON split.
The latest Motorolas I have in my stash are 96, and the earliest ON's from 2000 (samples direct from ON). If anything fell on the wrong side date wise I'd call it a fake for sure, and anything in between 1996 and 2000 would require testing.
While you guys were going on about the Fakes & Ebay, I went to Digi-Key & bought 4 On-Semi MJ21193's & 4 On-Semi MJ21194's. And all the Capacitors for the F-2583 Bias-Board.
Though I did find an Oddity when testing the Transistors on the F-2583:
TR07 & TR08, which are Green instead of Black, seem to have something blocking the Emitter on those Transistors. My Multimeter doesn't show anything on the Emitters of those 2 Transistors. I figured that is due to being in the Circuit.
If you guys know anything about the F-2583's TR07 & TR08 Transistors, I would appreciate any advice. Both seem to do the same thing, and they might be doing what they are supposed to do. I DID Properly set the DC-Offset on the Left-Channel with the power to the Right-Channel F-2581's disconnected. The AU-11000 powered up like it did, and I was able to Adjust the DC-Offset with the Trim closest to the Rear, VR01. I didn't dare mess with the Current-Bias, as I left it all the way Clockwise, which is the Minimum Position according to the Service Manual. Once I get the New On-Semi MJ2119x's & Bias-Board Caps, and Install them, I will find out if the Current Bias Adjustment works Properly. And hopefully, it will go Smooth!
Though I did find an Oddity when testing the Transistors on the F-2583:
TR07 & TR08, which are Green instead of Black, seem to have something blocking the Emitter on those Transistors. My Multimeter doesn't show anything on the Emitters of those 2 Transistors. I figured that is due to being in the Circuit.
If you guys know anything about the F-2583's TR07 & TR08 Transistors, I would appreciate any advice. Both seem to do the same thing, and they might be doing what they are supposed to do. I DID Properly set the DC-Offset on the Left-Channel with the power to the Right-Channel F-2581's disconnected. The AU-11000 powered up like it did, and I was able to Adjust the DC-Offset with the Trim closest to the Rear, VR01. I didn't dare mess with the Current-Bias, as I left it all the way Clockwise, which is the Minimum Position according to the Service Manual. Once I get the New On-Semi MJ2119x's & Bias-Board Caps, and Install them, I will find out if the Current Bias Adjustment works Properly. And hopefully, it will go Smooth!
*I just Realized how EASY it was to Remove these TO-3 Amplifier-Transistors!!
Sansui made it Harder to remove the Bias Board than to remove the Sanken TO-3 Power Transistors. I still don't understand why Sansui didn't just use Plugs for ALL the wiring to the Bias Board. Make it a pain to de-solder & re-solder every time.
Sansui made it Harder to remove the Bias Board than to remove the Sanken TO-3 Power Transistors. I still don't understand why Sansui didn't just use Plugs for ALL the wiring to the Bias Board. Make it a pain to de-solder & re-solder every time.
They did use plugs for the F-2583 driver/bias board? Someone mustve soldered the wires to the driver board pins before you got it.*I just Realized how EASY it was to Remove these TO-3 Amplifier-Transistors!!
Sansui made it Harder to remove the Bias Board than to remove the Sanken TO-3 Power Transistors. I still don't understand why Sansui didn't just use Plugs for ALL the wiring to the Bias Board. Make it a pain to de-solder & re-solder every time.
Seriously, I get it- you got burnt on eBay once and think everything is fake, so every opportunity you get to type out the same 'warning' you go off on a misinformed, misleading rant. Give it up.
It is not the truth, there are thousands of sellers who sell surplus, NOS and liquidate vast stock holdings of obsolete, ex-service centre parts, OEM stockpiles and have been doing so for years. There is also a growing industry in obtaining obsolete semis from industrial machinery 'pulls' and this is a great way of obtaining rare parts.
I've only ever bought fakes once, and that was a deliberate purchase to compare performance and internal dies for my own edification.
What you need to understand is there are billions of unused, NOS semis around the world and they will all undoubtedly hit the secondary market over time and it is foolish to advise others to exclude the world's largest online marketplace, the one with no geographical borders, simply because YOU cannot determine real from fake.
As for Motorola transistors, I could pull out 50 new (NOS) with date codes back to the 1970s right now, or a pile of new (NOS obsolete) NEC T0220s I have had since the 1970s and you would proclaim them as fake. That's ridiculous isn't it?
No affiliation with eBay and I don't sell semis either, for the record.
It is not the truth, there are thousands of sellers who sell surplus, NOS and liquidate vast stock holdings of obsolete, ex-service centre parts, OEM stockpiles and have been doing so for years. There is also a growing industry in obtaining obsolete semis from industrial machinery 'pulls' and this is a great way of obtaining rare parts.
I've only ever bought fakes once, and that was a deliberate purchase to compare performance and internal dies for my own edification.
What you need to understand is there are billions of unused, NOS semis around the world and they will all undoubtedly hit the secondary market over time and it is foolish to advise others to exclude the world's largest online marketplace, the one with no geographical borders, simply because YOU cannot determine real from fake.
As for Motorola transistors, I could pull out 50 new (NOS) with date codes back to the 1970s right now, or a pile of new (NOS obsolete) NEC T0220s I have had since the 1970s and you would proclaim them as fake. That's ridiculous isn't it?
No affiliation with eBay and I don't sell semis either, for the record.
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I think you are speaking from the buying experience of a seasoned tech. but most DIYs here are hobbyists, occasionally dabbling in buying parts at the cheap and easy end of the on-line market. Some alleged Motorola/On-semi TO3s can be bought for less than one USD and that's delivered free too - almost anywhere. So where did these below cost, new semis really come from? Begin with the real situation DIYs face when sourcing semis here: Counterfeit Transistors
The crunch point in buying, whether fakes or just poor copies, is when you receive product that is not what you bargained for. Often there is an obvious switcheroo between the pic and description you bought on and the goods received. They may even be acceptable second-source products for some applications but if you ordered Sanken LAPTs by their full JIS part number and received clearly non-Sanken, standard triple-diffused substitute grade product from ISC for example, as I have more than once, you'd be peeved too, no?
Faked semis are not a rare or trifling problem regardless of how many billion good semis may be lying in warehouses around the globe. It's also pretty harsh of you to lash out at the guys who don't have the awareness or buying experience or contacts of pros, perhaps like yourself, in the service business. So to rant about the buying incompetence of newbies and hobbyist members rather than the dishonesty of the sellers that likely did pass off inferior goods of one sort or another on them, is inappropriate, IMV.
I think a degree of honesty is needed here, after all, 99% of this stuff is used in mains connected equipment and potentially lethal.
I've just seen thread after thread where certain member/s post 'everything on eBay is fake' when the statement is false and far from the truth.
And yes, "buying incompetence" IS the problem. Caveat Emptor. (The principle that the buyer alone is responsible for checking the quality and suitability of goods before a purchase is made.)
Fake stuff has been around for millennia. The Romans knew it- hence the Latin referenced above. Jewellery, currency, gold, silver, clothing, watches (maybe sundials in Roman times) etc etc. China didn't start it, are not to blame and while people continue to make uninformed buying decisions, it will continue.
In Australia, people go on holidays to Bali to buy fake brand name clothing, Rolex watches etc- because they want to. They know the stuff is fake, but they buy it anyway. They buy it because it's so cheap and looks all the world like they paid a whole lot of money for it.
Capacitors with nice gold Nichicon FG screen printing, or Rubycon black gates are perfect to fake. Hobbyists think they are magic capacitors and pay stupid money for them. Rare, high powered, high fT complementary Sankens are another thing easy to fake. If you want a real Sanken, go look at their latest offerings- there's several in either T03P or MT200 that offer the same or better specs than the commonly faked obsolete ones out there. If you want genuine- buy from Japanese suppliers, they still have millions of them over there, after all, all the big manufacturers were in Japan then and fabricated billions.
My point would be for 'newbies'; if you don't feel confident that the components you are purchasing and using in your projects and repairs are genuine and safe and won't spectacularly fail, cause injury, electrocution and/or render an otherwise functional design unsafe, then educate yourself on how to determine the differences, work out how to test and verify components and buy from a source/s that are trustworthy.
I source my rarer components (semis) directly out of Japan, from an industry supplier of over 30 years.
In short, accept the responsibility in determining provenance rests with you, and you alone.
Rant? Perhaps, but it needs to be said.
I've just seen thread after thread where certain member/s post 'everything on eBay is fake' when the statement is false and far from the truth.
And yes, "buying incompetence" IS the problem. Caveat Emptor. (The principle that the buyer alone is responsible for checking the quality and suitability of goods before a purchase is made.)
Fake stuff has been around for millennia. The Romans knew it- hence the Latin referenced above. Jewellery, currency, gold, silver, clothing, watches (maybe sundials in Roman times
) etc etc. China didn't start it, are not to blame and while people continue to make uninformed buying decisions, it will continue. In Australia, people go on holidays to Bali to buy fake brand name clothing, Rolex watches etc- because they want to. They know the stuff is fake, but they buy it anyway. They buy it because it's so cheap and looks all the world like they paid a whole lot of money for it.
Capacitors with nice gold Nichicon FG screen printing, or Rubycon black gates are perfect to fake. Hobbyists think they are magic capacitors and pay stupid money for them. Rare, high powered, high fT complementary Sankens are another thing easy to fake. If you want a real Sanken, go look at their latest offerings- there's several in either T03P or MT200 that offer the same or better specs than the commonly faked obsolete ones out there. If you want genuine- buy from Japanese suppliers, they still have millions of them over there, after all, all the big manufacturers were in Japan then and fabricated billions.
My point would be for 'newbies'; if you don't feel confident that the components you are purchasing and using in your projects and repairs are genuine and safe and won't spectacularly fail, cause injury, electrocution and/or render an otherwise functional design unsafe, then educate yourself on how to determine the differences, work out how to test and verify components and buy from a source/s that are trustworthy.
I source my rarer components (semis) directly out of Japan, from an industry supplier of over 30 years.
In short, accept the responsibility in determining provenance rests with you, and you alone.
Rant? Perhaps, but it needs to be said.
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Sure, some individuals do parrot dire warnings here but not without justification. The cheap stuff can be impossibly cheap and the power semis usually are fakes or at least bad copies, some not even resembling the seller's own pics.
In reality there is little that individual buyers can do to assess on-line marketed products before purchase. All they have is a dodgy thumbnail pic of a dodgy product marked with a desirable part number. It also becomes clear that the seller has no clue or interest in giving further information for a trivial sale either.
I think DC load testing is a method newbies could focus on. It's not necessarily expensive, undemanding on instruments and education but tells us a lot about our semis. If they fail within spec, it's likely the best outcome.
In reality there is little that individual buyers can do to assess on-line marketed products before purchase. All they have is a dodgy thumbnail pic of a dodgy product marked with a desirable part number. It also becomes clear that the seller has no clue or interest in giving further information for a trivial sale either.
I think DC load testing is a method newbies could focus on. It's not necessarily expensive, undemanding on instruments and education but tells us a lot about our semis. If they fail within spec, it's likely the best outcome.
When looking for obsolete devices e-bay may be the only place to take a chance but I see no sense buying currently manufactured devices from e-bay. I buy straight from ON Semi at about half of retail, that's at 25 pieces. If you're in the repair business or a busy hobbyist 25 pieces isn't all that many. When you think about it that's only 12 pieces at retail prices. I buy lots of obsolete American devices from the surplus places mentioned by Resto-John and haven't been taken yet.
Craig
Craig
Anyway - Back to Properly Setting the DC-Offset & Bias Current Adjustments...
HOW do you Adjustment then on a F-2583 Bias-Board?!?
If the VR01/VR02's & where the VR03 & VR04 are on the Diagram in the Service Manual, then WHAT is the True Way to do these Adjustments after replacing All 8 T-03 Power-Resistors with OnSemi MJ21193's & MJ21194's off DigiKey, and all the Capacitors on the Bias-Board?!?!?
HOW do you Adjustment then on a F-2583 Bias-Board?!?
If the VR01/VR02's & where the VR03 & VR04 are on the Diagram in the Service Manual, then WHAT is the True Way to do these Adjustments after replacing All 8 T-03 Power-Resistors with OnSemi MJ21193's & MJ21194's off DigiKey, and all the Capacitors on the Bias-Board?!?!?
I've just Installed NEW OnSemi 93 & 94's into the F-2581's, and NEW Capacitors into the F-2583 Bias-Board. And Guess What?!? It STILL Overheats!!
I tested ALL the Transistors (in circuit) and All Components on the F-2581's.
Except for funny Readings at the Emitters of TR07 & TR08 on the F-2583, I can't find ANYTHING Wrong with it!! And it's now just a heat-bomb.
The Power Light even turns Red now about about 8-10 minutes.
*If in case I need to Replace TR07 & TR08 on the Bias-Board, WHAT exactly should I replace it with?!? Cause there isn't much info to go by on the component. I know someone posted above that it's a PNP. That's about all I know about it.
A Specific Example would be Most Appreciated.
I tested ALL the Transistors (in circuit) and All Components on the F-2581's.
Except for funny Readings at the Emitters of TR07 & TR08 on the F-2583, I can't find ANYTHING Wrong with it!! And it's now just a heat-bomb.
The Power Light even turns Red now about about 8-10 minutes.
*If in case I need to Replace TR07 & TR08 on the Bias-Board, WHAT exactly should I replace it with?!? Cause there isn't much info to go by on the component. I know someone posted above that it's a PNP. That's about all I know about it.
A Specific Example would be Most Appreciated.
I've just Installed NEW OnSemi 93 & 94's into the F-2581's, and NEW Capacitors into the F-2583 Bias-Board. And Guess What?!? It STILL Overheats!!
I tested ALL the Transistors (in circuit) and All Components on the F-2581's.
Except for funny Readings at the Emitters of TR07 & TR08 on the F-2583, I can't find ANYTHING Wrong with it!! And it's now just a heat-bomb.
The Power Light even turns Red now about about 8-10 minutes.
*If in case I need to Replace TR07 & TR08 on the Bias-Board, WHAT exactly should I replace it with?!? Cause there isn't much info to go by on the component. I know someone posted above that it's a PNP. That's about all I know about it.
A Specific Example would be Most Appreciated.
The schematic is wrong for the trimpots on the F-2583 driver board. Someone has made up a proper guide on it.Ive been trying to find it for you,its on DIY Audio here somewhere?
At this point, I just need to know where to find Replacements for the TR07 & TR08, which both have 'A818' written on them. In the Service Manual, it says they are 2SA818's.
(Same thing, more detailed info)
After desoldering and resoldering the F-2583 Bias Board wires multiple times, replacing all the Caps and testing everything else, I've about had it.
Now, it comes down to 2 identical Transistors, and I can't even find them. :/
(Same thing, more detailed info)
After desoldering and resoldering the F-2583 Bias Board wires multiple times, replacing all the Caps and testing everything else, I've about had it.
Now, it comes down to 2 identical Transistors, and I can't even find them. :/
The replacement for 2SA818 is 2SA914 and TR04/05 2SC1628 complimentary for the 2SA914 is 2SC1953. Check your pinouts om the 2SA818s are installed correctly first and check for cold solder joints in that area? Post a photo of the grounding wires on the solder side of your driver board, you couldve got them wrong?
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No! I shouldve said TR05 and TR06= 2SC1628 that can be replaced with 2SC1953 the complimentary to 2SC1953 is 2SA914 that you can use instead of the 2SA818.Did you check your pinouts?
Redrooster - This Amp was Overheating when he brought it too me. That's what he [Initially] wanted me to Fix. After attempting to adjust the DC-Offset & Current Bias, 2 of the 4 Power-Transistors blew on the F-2581 Power-Amp Boards. (1 of the PNP's & 1 of the NPN's). I went ahead and changed the All, installing the Correct MJ2119x's in they're respective Location, replacing the 2SC1116's with MJ21194G's & the 2SA747's with MJ21193G's. I also replaced all the Electrolytic Caps on the F-2583 Bias Board. I found 2 to be abit over 20%-off in Values, and 1 to be Totally shorted.
Each of the original Sanken Power-Transistors gingled like Bells after removal.
So they were all about to go anyway. But now it still Overheats... Only MUCH Faster this time!! It used to take over 25 minutes when it was brought to me. Now, it just takes 5 minutes. :/
Each of the original Sanken Power-Transistors gingled like Bells after removal.
So they were all about to go anyway. But now it still Overheats... Only MUCH Faster this time!! It used to take over 25 minutes when it was brought to me. Now, it just takes 5 minutes. :/
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