They are now live in the store. Initial pricing and limits: $34.95 per unit and a limit of 2 units per customer per month.
Matched JFET pairs (Grade B)
Matched JFET pairs (Grade B)
Thanks Jason
Ordered 2 units and it's always pleasure to
support work of DiyAudio Store Team
Greetings
Unhappy customer!
Hi All,
I have been patiently waiting for some time for the fets to come back into stock and have been checking the website everyday. Today I log on to find that the store is out of stock already not more than 12 hours after they have gone on sale!
How long before we can get some more?🙁
Tony
Hi All,
I have been patiently waiting for some time for the fets to come back into stock and have been checking the website everyday. Today I log on to find that the store is out of stock already not more than 12 hours after they have gone on sale!
How long before we can get some more?🙁
Tony
Bigtone.
Email me.
I may have something to suit in either lsk/j or 2sk/j
Have you searched jFETs in swap meet?
Email me.
I may have something to suit in either lsk/j or 2sk/j
Have you searched jFETs in swap meet?
There is an overlap on grades where a B grade could be as much as 12 idss and a C grade is 10 idss. I hope that is the case. Three of my fets are C grade and one 170 does not have a grade. I am going to check the idss later today and I will report my findings.
David
David
I am happy to report my findings testing the idss for the matched jfets.
The first pair
k170 10.6 idss
j74 10.59 idss
2nd pair
k170 10.6 idss
j74 10.57 idss
I was using a 9 volt battery that tested 9.6 volts. I am very satisfied with the results and how well both pairs matched to each other. Hats off to the Diyaudio store.
David
The first pair
k170 10.6 idss
j74 10.59 idss
2nd pair
k170 10.6 idss
j74 10.57 idss
I was using a 9 volt battery that tested 9.6 volts. I am very satisfied with the results and how well both pairs matched to each other. Hats off to the Diyaudio store.
David
+1 Yes hats off for quality efforts to the DiyAudio Store.
Thanks David for your report it's save me from sleepless night 😀
Christophe
Hi Andrew,
I have tried to send you a PM but you have exceeded your mail box limit!
I have tried all the usual places for jFets, but no one I know has stock at present.
Cheers
Tony
Very sorry Tony, and yes, they sold out within 12 hours. If we emailed everybody (eg the whole store list) they would sell out before the email queue had finished sending. Currently, staying tuned to this thread you are reading is the best chance you will get. It's a difficult situation, and we are going to try to find a fairer way to distribute these as fairly as possible in the future.
@ Diyers
Grade letter on matched LSK pairs is C not B?
Best regards
Some of the JFETs have the letter C on them, and some are unmarked. The marking of C on the transistor is not a grade marking. The grade is unmarked. Really. We have double triple confirmed with LS, who supply us the different grades in separate packaging and we are very careful to ensure we don't mix them up. The C on them has nothing to do with the grade, the grade is not marked. You just have to trust us 🙂
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Experience with grade D jfets
I recently ordered 8 each of the LSK170D and LSJ74D (grade-D) jfets. Here are the measured Idss and transconductance values for these fets. It should be noted that none of the LSK170 jfets had an Idss above 18ma which is the low end of the grade-D range, but all of the LSJ74 jfets had Idss within the grade-D range. Also note that LSJ74 74 was defective, with an unusually low transconductance value.
part# Idss(ma) gm(mS)
LSJ74D 70 19.22 36.20
LSJ74D 73 19.60 34.80
LSJ74D 72 20.32 34.80
LSJ74D 76 20.70 35.70
LSJ74D 74 20.82 13.10
LSJ74D 75 21.06 34.50
LSJ74D 71 21.66 35.20
LSJ74D 77 21.90 35.20
LSK170D 60 12.30 32.50
LSK170D 62 12.60 33.00
LSK170D 61 13.12 33.00
LSK170D 63 14.58 33.30
LSK170D 65 15.54 33.60
LSK170D 67 15.90 33.20
LSK170D 64 16.60 33.10
LSK170D 66 16.62 33.30
I recently ordered 8 each of the LSK170D and LSJ74D (grade-D) jfets. Here are the measured Idss and transconductance values for these fets. It should be noted that none of the LSK170 jfets had an Idss above 18ma which is the low end of the grade-D range, but all of the LSJ74 jfets had Idss within the grade-D range. Also note that LSJ74 74 was defective, with an unusually low transconductance value.
part# Idss(ma) gm(mS)
LSJ74D 70 19.22 36.20
LSJ74D 73 19.60 34.80
LSJ74D 72 20.32 34.80
LSJ74D 76 20.70 35.70
LSJ74D 74 20.82 13.10
LSJ74D 75 21.06 34.50
LSJ74D 71 21.66 35.20
LSJ74D 77 21.90 35.20
LSK170D 60 12.30 32.50
LSK170D 62 12.60 33.00
LSK170D 61 13.12 33.00
LSK170D 63 14.58 33.30
LSK170D 65 15.54 33.60
LSK170D 67 15.90 33.20
LSK170D 64 16.60 33.10
LSK170D 66 16.62 33.30
Hello lhquam,
Please email the Helpdesk with your shipping details so we can send you replacements as well as send you a return shipping label for the defective JFETs so we can have LS look into these. Thanks.