I have been looking to pick up some 2SK117s for some time, but knowing they are no longer produced, the likelihood of getting fakes are pretty high. I know that things can be faked to make the item look as authentic as possible, but I found this seller out of Japan, has 100% positive feedback, and if he indeed has the original box and such, I would put my money on these being authentic. Does anyone have the same opinion of them?
I’m wondering if I even need them though. I know this is all circuit dependent, so in the end I guess really wouldn’t know. I have at least a couple hundred each 2SK170 and 2SJ74, that I know with absolute certainty are the real thing. In most instances would the 2SK170 be a good sub for the 2SK117? In what instances would it not be a good sub other than circus that use higher than 40 V? Another option I was thinking of was using the SMD part 2SK209, putting it on a small adaptor board. It does have about half the dissipation of the 2SK117 though.
I like having large quantities on hand, especially if things are no longer available, which is why I have a couple hundred each of the 170/74 combo. So I don’t mind buying 200 of the SK117 and if I were to get the 2SK209 I would grab a couple hundred of them as well.
I was hoping to get opinions of others in here. If those 117s do look authentic would it be best if I grabbed those or do you think in 99% of instances the 170 will work? Or with the combo of the 170 and the 209 I should be good to go?
Dan
I’m wondering if I even need them though. I know this is all circuit dependent, so in the end I guess really wouldn’t know. I have at least a couple hundred each 2SK170 and 2SJ74, that I know with absolute certainty are the real thing. In most instances would the 2SK170 be a good sub for the 2SK117? In what instances would it not be a good sub other than circus that use higher than 40 V? Another option I was thinking of was using the SMD part 2SK209, putting it on a small adaptor board. It does have about half the dissipation of the 2SK117 though.
I like having large quantities on hand, especially if things are no longer available, which is why I have a couple hundred each of the 170/74 combo. So I don’t mind buying 200 of the SK117 and if I were to get the 2SK209 I would grab a couple hundred of them as well.
I was hoping to get opinions of others in here. If those 117s do look authentic would it be best if I grabbed those or do you think in 99% of instances the 170 will work? Or with the combo of the 170 and the 209 I should be good to go?
Dan
Looks like 170 are almost the same thing. Papa uses J113 series a lot. JFETs are not "precision" devices so either the circuit is forgiving, or you hand pick usually the Idss you want. The K117 does have a higher voltage rating than most, if that matters.
https://www.mouser.com/datasheet/2/308/MMBFJ113_D-2303036.pdf
https://www.mouser.com/datasheet/2/308/MMBFJ113_D-2303036.pdf
I ordered and should receive on Monday 100 each of the BL, GR, and Y grade of the 2SK209. So is the only negative of these compared to the 2SK117 is that they only have half the dissipation rating? Hopefully that will not be an issue in most circuits.
Dan