I don't get it. I couldn't see any relationship with the pictures. What have been your assumptions?
Hehe thanks
I know that I don't know about the Hitachi stuffs because I don't care. I haven't looked up the Renesas, or even Lexicon. My Hitachi stock is purchased long before the crisis or Kobe. I was a believer that latfet would someday found a proper circuit to unleash its potential (no good mosfet amplifiers back then).
And the point is? (Related to my "strange" post)
From the shape, non of them look like the Hitachi. From the look of the material, it is hard to guess from picture, but the last ones (KT897) I think are closer.
I don't understand this. I mentioned about solution (solvent), because I want to know if old Hitachi (which have grayish color) can be made like "new" by cleaning it with certain solution. Old bipolar Hitachi (2SD types) are even worse, they are so dark and cannot be cleaned IME.
So it was strange to me to suddenly see Hitachi with bright and new casing after previously "missing" from the market. None of the Hitachi I have seen before clean like that.
Yes, I have been confused also what alloy is used to be able to corrode like that. I don't think it is a tinned copper. It is Aluminum mostly.
And yes, it is hard to believe that something like that can be faked.
It was their sudden re-appearance in local audio market that confused me. May be somebody bought-out the stuffs when the price was still cheap. I know at least one guy who did that (coz he knew the price will went up), but the appearance was not so good with the usual oxide/corrosion, so the confusion.
As already stated, Alfet=Magnatec=Exicon=ClassD, all made by Semelab, as far as I remeber older discussions here or elsewhere, they are made in their fab (Semefab).
Housing could well be made in far east as someone suggested.
All the same die(s), single and double die variants, P and N, some older are 160V, most newer 200V rated, metal and plastic.
The mounting plate of a Semelab/Magnatec TO-3 lateral MOSFET has a thickness of 1.5mm
The one of an Hitachi TO-3 is well over 3mm, case height is also >2.5mm more.
A Semelab lateral weighs 12 grams, a Hitachi original does 18 grams.
Specific weight of steel is 7.9
For copper it's 8.9
Aluminum does 2.7
Even if someone is uninformed that the Japanese devices have an alloy case, nor realised that aged ones have the exact same appearance of corroded aluminum bicycle/car wheels, the size/weight differences should have been a dead giveaway.
Doesn't even require owning any, merely the transparency of mind to read and compare datasheets.
(all of which can be downloaded for free by pressing a button with the right index finger)
(I own way over a thousand Hitachi TO-3 lateral MOSFETs, plus various plastic versions and SML/Magnatec TO-3's, btw)
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And what do you want to say with this???
That Semelab TO-3 laterals are the fakes????
I think Jay talked about fake Hitachis, but not about Semelab parts (which are not fakes anyway). They are even better than the Hitachi Parts....
And happy soldering of your many TO-3's btw.
What I was saying :
1 Hitachi TO-3's have an alloy case
2 Semelab TO-3's have a steel* case, both the older types as e.g. BUZ900/901/905/906 as later model numbers.
Only other semi manufacturer that produced devices with aluminum TO-3 cases was Motorola, and that was a very long time ago.
Anyone in his right mind who'd throw fake Hitachi devices on the market, and bother to manufacture alloy cases for them, would go the mile to age the devices to look original.
Those who punch out shiny fakes, don't even take the trouble, just pick cheap steel TO-3 cases.
Plenty of fools around, who don't even bother to read a datasheet.
Thanks for the solder wishes, I've built power amp designs with Hitachi Lateral MOSFET output stages since the mid 1980s, reason I've known for 30+ years that the cases are made of aluminum.
I'm also one of those folks who can buy whatever they want, the ones Jay likes to post about on occasion.
http://www.diyaudio.com/forums/soli...age-audio-power-amplifier-22.html#post2533796
A good designer is an informed one, reading and understanding datasheets is just a basic requirement.
(* need a picture with a reel of Semelab TO-3 lateral MOSFETs to demonstrate that the cases are magnetic/steel ? )
1 Hitachi TO-3's have an alloy case
2 Semelab TO-3's have a steel* case, both the older types as e.g. BUZ900/901/905/906 as later model numbers.
Only other semi manufacturer that produced devices with aluminum TO-3 cases was Motorola, and that was a very long time ago.
Anyone in his right mind who'd throw fake Hitachi devices on the market, and bother to manufacture alloy cases for them, would go the mile to age the devices to look original.
Those who punch out shiny fakes, don't even take the trouble, just pick cheap steel TO-3 cases.
Plenty of fools around, who don't even bother to read a datasheet.
Thanks for the solder wishes, I've built power amp designs with Hitachi Lateral MOSFET output stages since the mid 1980s, reason I've known for 30+ years that the cases are made of aluminum.
I'm also one of those folks who can buy whatever they want, the ones Jay likes to post about on occasion.
http://www.diyaudio.com/forums/soli...age-audio-power-amplifier-22.html#post2533796
A good designer is an informed one, reading and understanding datasheets is just a basic requirement.
(* need a picture with a reel of Semelab TO-3 lateral MOSFETs to demonstrate that the cases are magnetic/steel ? )
So with alloy you always meant aluminum....OK, now I get it. In my language, alloy is just about any mixture of any metal.
Btw, there is no hint on datasheets I have that Hitachi's are packaged with aluminum cases.
No thanks. Don't have the wish to use TO-3 transistors.
The plastic ones are OK, for a good, informed designer, and even for me.
http://www.bcae1.com/repairbasicsforbcae1/images/transistordies/IMG_5503_Hitachi_2SJ50b.jpg
- The pitting of the mounting plate surface demonstrates it's an alloy with aluminum as the highest volume portion.
- As does the chewing-gum appearance of the remains of the sawn-off hat.(thicker than a steel TO3 hat)
Area of an ellipse : (Pi x height x width)/4
TO3 mounting plate for pure aluminum : (3.14 x 4 x 2.5 x 0.33*)/4 x 2.7 ~ 7 grams
* mounting plate thickness is 3.3mm max.
See the texture and color of the heat spreader under the die, mind the top part, much softer material (<= indent) than aluminum.
The much higher specific weight of the heat spreader accounts for the lost grams of the 18 total.
A Dutch electronics magazine carried a detailed analysis of the Hitachi TO3 case composition in the late 1980s.
Hitachi never did in any of the lateral MOSFET application notes, not even in the 74-page publication of 1985.
=> notice the punching rupture line on the side of the mounting plate. The location is a giveaway of the aluminum volume percentage of the alloy.
- The pitting of the mounting plate surface demonstrates it's an alloy with aluminum as the highest volume portion.
- As does the chewing-gum appearance of the remains of the sawn-off hat.(thicker than a steel TO3 hat)
Area of an ellipse : (Pi x height x width)/4
TO3 mounting plate for pure aluminum : (3.14 x 4 x 2.5 x 0.33*)/4 x 2.7 ~ 7 grams
* mounting plate thickness is 3.3mm max.
See the texture and color of the heat spreader under the die, mind the top part, much softer material (<= indent) than aluminum.
The much higher specific weight of the heat spreader accounts for the lost grams of the 18 total.
A Dutch electronics magazine carried a detailed analysis of the Hitachi TO3 case composition in the late 1980s.
Hitachi never did in any of the lateral MOSFET application notes, not even in the 74-page publication of 1985.
=> notice the punching rupture line on the side of the mounting plate. The location is a giveaway of the aluminum volume percentage of the alloy.
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Measured bunch of capacitors on 4000€ lc bridge, any electrolytes above 1000Hz have capacity <50%; and 10-20kHz they are like chokes..
Apply this info on common amplifiers PSRR_dB/freq charts....
any electrolytes above 1000Hz have capacity <50%; and 10-20kHz they are like chokes..
Apply this info on common amplifiers PSRR_dB/freq charts....
Did you measure Black Gate also? I usually don't add smaller bypass cap when using Black Gate. Currently I'm working with Apex' FX8 where the front end supply is the main supply RC filtered with 10 Ohm and 47uF. I'm using BG. Do you think I should parallel with MKP/FKP? What size?
i believe i have the correct ones for the discrete amps - picking up the NTE equivalents now to test a 1,2 and 3 pair lfet amp. Driver stage is omitted lfets are being pushed right out of the class A, VAS stage. Cascading vfa in, hawksford in the vas, shouldn't have to do so much current mirroring as i am bootstrapping transistors. I do not believe i will be using many PCBs, I don't trust my abilities for proper grounding with home etching so will be doing everything point to point - possibly using a bridge rectifier bolted to the chassis for 4 fast on ground connects or make an bolt on piece of metal with fast on soldered. i have a bunch of bridges but flipped it to Shottsky diodes for FWB rectification so i have a bunch i don't have a use for at this point. figure fastons allow me to take it apart faster and easier should the need arise.
this is where i buy mine - i get other stuff from mouser or digikey. fast delivery but i like how some of the new packages from others are not only double dye but also have 2 additional leads so are pnp and npn in 1 chip. makes pairing on single set drivers easier