I have a set matched-16 TOS JFETs(8xK170BL+8xJ74BL) for sale.
The Idss is 6.9mA.
They are genuine and were sourced directly from Japan.
Asking $140. Shipping from Thailand by registered post is $14 to the US and $12 to Europe.
Please PM me if you are interested.
Thank you
The Idss is 6.9mA.
They are genuine and were sourced directly from Japan.
Asking $140. Shipping from Thailand by registered post is $14 to the US and $12 to Europe.
Please PM me if you are interested.
Thank you
I want to provide more info about the these JFETs.
The K170 are from later productions with edged letterings.
The J74 are from older productions with screen letterings. The surface of the J74's' legs of the J74 are slightly dull. Please see attach photo.
They both are genuine Toshiba parts.
The K170 are from later productions with edged letterings.
The J74 are from older productions with screen letterings. The surface of the J74's' legs of the J74 are slightly dull. Please see attach photo.
They both are genuine Toshiba parts.
Attachments
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I made some quick measurement to calculate the Gm of these older production of TOS:2SJ74(Silk screen lettering), newer production of TOS:2SJ74(edged lettering), and Linear System:LSJ74
Idss(mA). Vp(V). Gm(mS)
Old 1. 6.76 0.48 28.17
Old 2. 7.20 0.52 27.69
Old 3. 8.6 0.49 35.10
New1. 7.24 0.51 28.28
New2. 7.35 0.52 28.54
New3. 8.57 0.54 31.74
LSJ1. 3.71 0.37 20.22
LSJ2. 5.14 0.43 24.0
LSJ3. 6.67 0.49 32.48
Vp is the gate pinch-off voltage
Gm = -2Idss/Vp (where the transconductance curve meets the y-axis)
Toshiba data sheet states that the Gm is (typ) 22 mS with 8 mS(min)
Idss(mA). Vp(V). Gm(mS)
Old 1. 6.76 0.48 28.17
Old 2. 7.20 0.52 27.69
Old 3. 8.6 0.49 35.10
New1. 7.24 0.51 28.28
New2. 7.35 0.52 28.54
New3. 8.57 0.54 31.74
LSJ1. 3.71 0.37 20.22
LSJ2. 5.14 0.43 24.0
LSJ3. 6.67 0.49 32.48
Vp is the gate pinch-off voltage
Gm = -2Idss/Vp (where the transconductance curve meets the y-axis)
Toshiba data sheet states that the Gm is (typ) 22 mS with 8 mS(min)
Attachments
FS:One matched octet of TOS:K170/J74 “BL” Idss=9.2mA
$55/set*
I have multiple sets with Idss <9.2-10mA>range
Shipping cost $10
Payment by PayPal” friends and family”
Thank you
*Price reduced due to strong US$
$55/set*
I have multiple sets with Idss <9.2-10mA>range
Shipping cost $10
Payment by PayPal” friends and family”
Thank you
*Price reduced due to strong US$
Hi
Can I ask the source of your 2SJ74 ?
The lettering on the 2SK170 looks genuine. It seems different on your J74.
Thanks
Eric
Can I ask the source of your 2SJ74 ?
The lettering on the 2SK170 looks genuine. It seems different on your J74.
Thanks
Eric
The J74 of the older production dates have the screen lettering. I sourced them from a reliable source in Japan quite a while back. They are absolutely genuine.
Prakit
Prakit
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The number 7 from genuine J74 and 2SK170 is normally curved and not straight like the J74 you’re selling....😟
I doubt about your “genuine “ J74.
I have a near full box of J74GR also with silk-screen lettering. Check out how the “7” looks.
You’d better do some more research.
I have a near full box of J74GR also with silk-screen lettering. Check out how the “7” looks.
You’d better do some more research.
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Box full or 10 box full doesn’t change anything, search this website and draw your own conclusions. Members have been warned at least.
Example of genuine JFET;
https://www.ebay.com/itm/256070315974
Enough said.
Cheers
Eric
Example of genuine JFET;
https://www.ebay.com/itm/256070315974
Enough said.
Cheers
Eric
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