Gpapag, if I added spell checking and editing for grammar and removed the obsure sarcasm it would be all work and no play.When I went to MIT you could still submit term papers in longhand, pity those teachers.
>Aby... who?
>Aby Normal !
http://www.youtube.com/watch?v=QLTdQG1SP5w&feature=related
George
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Thank you.
I found genuine Toshiba parts, from a person living near by me: 20x Toshiba 2SJ74BL + 2SK170BL (10 Matched pairs) | eBay .
Joshua, it is great that you could find parts very close to your home. As this shows, it is not impossible to get these parts in small and usable quantities. AND there will always be 'something' with jfets that we can continue to use, even if they become somewhat more expensive from the lowest prices, and perhaps have to be selected from a small batch.
I am more aware of the problems, today, with jfet design, than I ever have been, up to now, by going back to sources in the manufacturing of the jfets, and asking WHY we have so much trouble, today, compared to sometime in the past. Like vacuum tubes, stock up, if you want them easy and available in future, but they will probably always be available.
I am more aware of the problems, today, with jfet design, than I ever have been, up to now, by going back to sources in the manufacturing of the jfets, and asking WHY we have so much trouble, today, compared to sometime in the past. Like vacuum tubes, stock up, if you want them easy and available in future, but they will probably always be available.
Now that Jfets are taken care of, what next? Ed Simon is taking care of fixed resistors, Charles and I have settled on Rel RT polystyrene caps as the best overall film cap, I can't get the super quality silver wire that BEAR (yes, the guy on this website) used to supply, AND insist on, so it is tough to recommend it. Everybody has an opinion about how much to invest in a SOLID aluminum case.
Perhaps a few tips to the serious:
One, test connectors, cap leads, resistor leads, etc with a strong magnet. If the parts 'fall in love' with the magnet, perhaps you should exclude them from your best efforts.
Still, Copperweld, Kovar, nickel plating, and other alloys might be slightly magnetic, and still be useful what they are necessary. Do not trust your eyes, alone. Test with a magnet.
Two, Avoid Mylar caps and most ceramics if possible. They might be just fine for some applications, but they have problems too.
Three, keep the audio thru-path as simple and as un-congested as possible. Straight forward, minimal path will win out.
That's about all that I can think of at the moment.
Perhaps a few tips to the serious:
One, test connectors, cap leads, resistor leads, etc with a strong magnet. If the parts 'fall in love' with the magnet, perhaps you should exclude them from your best efforts.
Still, Copperweld, Kovar, nickel plating, and other alloys might be slightly magnetic, and still be useful what they are necessary. Do not trust your eyes, alone. Test with a magnet.
Two, Avoid Mylar caps and most ceramics if possible. They might be just fine for some applications, but they have problems too.
Three, keep the audio thru-path as simple and as un-congested as possible. Straight forward, minimal path will win out.
That's about all that I can think of at the moment.
The bond pad should be ~100 microns. No logo, but these were laser branded which is not normal on fakes.
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Scott,
What I would really be interested to know, is whether the 2SK370 has the same die, or a smaller one ?
Unfortunately I do not have any 370's, else I would have sent you one. But Nelson has tons, and maybe he would sacrifice one for scientific curiosity ??
Patrick
I will need to do more as a group, it was harder than you think because we sell nothing in this package there was no jig. I'm not permitted to do the jet of fuming nitric that they use for this so I called in a favor.
Ayre K-5xeMP and Parasound Halo JC 2 on page 3 here...Ayre K-5xe<SUP>MP</SUP> line preamplifier | Stereophile.com
Not SY... but here's the reason
unless there is copper or nickel somewhere, gold is immune, aluminum, chromium, niobium,etc. is passivated, silicon non-reactive, etc...
strong oxidizers CAN be your friend...
Used to make metal jets for streaming RFNO and UDMH... <<- rocket propellant... gotta be the right stuff or you get BFRC
John L.
unless there is copper or nickel somewhere, gold is immune, aluminum, chromium, niobium,etc. is passivated, silicon non-reactive, etc...
strong oxidizers CAN be your friend...
Used to make metal jets for streaming RFNO and UDMH... <<- rocket propellant... gotta be the right stuff or you get BFRC
An externally hosted image should be here but it was not working when we last tested it.
John L.
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Joshua - hope your 2SJ74 jfets aren't the same high idss BL ones I bought from an Israeli seller on eBay . The surface of his jets are dull where the original device's label has been etched off chemically and reprinted as J74BL's and the seller claims they are mislabeled as the idss is really 17 to 19 ma (the high idss switching jfets mentioned by others). The visual clue is the etched surface of the devices face, not glossy like real ones. electrically testing them is of course the real answer, but as soon you see them look for a glossy sheen to the face, if it's flat and rough run away .
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