It’s the above schematic but with 470uF output cap. I adjusted the resistors to give 55mA bias. I don’t have amp anymore so don’t remember exact values. Use sim to derive. I would build the Pocket Class A though as it sounds much better.
There’s no equivalent. Close in performance and higher voltage is 2SK170BL but those are even harder to find. Plenty still available from Aliexpress or eBay. They are too small and cheap to fake so will be genuine as far as I have seen.
e.g., 10PCS BF862 JFET N-CHAN 20V SOT-23 ZETEX NEW | eBay
100 for $16:
Free shipping 100pcs/lot BF862,215 BF862 JFET N CHAN 20V SOT 23 Best quality-in Integrated Circuits from Electronic Components & Supplies on Aliexpress.com | Alibaba Group
e.g., 10PCS BF862 JFET N-CHAN 20V SOT-23 ZETEX NEW | eBay
100 for $16:
Free shipping 100pcs/lot BF862,215 BF862 JFET N CHAN 20V SOT 23 Best quality-in Integrated Circuits from Electronic Components & Supplies on Aliexpress.com | Alibaba Group
I read in a post here that the BF862 is recommended to run at 2/3 of the IDSS value ? Is there a reason for this ? What happens if the BF862 runs at a lower value than 2/3 of IDSS ? Will it still work ?
I tried testing the BF862 using a JFET tester circuit like this SMD jfet test jig and I got about 25ma IDSS.
I tried testing the BF862 using a JFET tester circuit like this SMD jfet test jig and I got about 25ma IDSS.
You can run a bit lower but these things are operating in Class A so try to keep some current flowing for best sound.
Sad reason to dredge up an old thread, but...
I recently purchased two lots of BF862 off of Ebay, from different sellers, and both were fakes.
Clearly visible under the microscope were the striations and gloss of the sanded & painted tops in place of the usual pebbled texture consistent with the other package surfaces, complete with sharp shoulders instead of the expected slight radius around the four edges. Laser markings were more inconsistent in alignment from part to part than they should have been - another subtle tell.
A few seconds under the flame of a butane torch, and the tiny die is easily liberated to the telling eye of the same microscope... the die look nothing like the genuine die photos posted elsewhere online:
Attachments
The offending parts were procured from the following listings:
Hot Sell 20PCS NEW 2AW BF862,215 BF862 JFET N-CHAN 20V SOT-23 | eBay
50PCS BF862 ORIGINAL JFET N-CHAN 20V SOT-23 | eBay
Caveat emptor!! These tiny parts are evidently not too small or cheap for dishonest sellers to bother grinding & re-marking something even cheaper.
Hot Sell 20PCS NEW 2AW BF862,215 BF862 JFET N-CHAN 20V SOT-23 | eBay
50PCS BF862 ORIGINAL JFET N-CHAN 20V SOT-23 | eBay
Caveat emptor!! These tiny parts are evidently not too small or cheap for dishonest sellers to bother grinding & re-marking something even cheaper.
... and here was the thread showing confirmed genuine die shots. Thanks to user stijena1973 for the pointer:
Bf862 purchased on ebay - labeled as 2AW2?
BF862 - low-noise N-Channel JFET : real vs fake : weekend die-shot : ZeptoBars
Bf862 purchased on ebay - labeled as 2AW2?
BF862 - low-noise N-Channel JFET : real vs fake : weekend die-shot : ZeptoBars
I took another part out of the packaging today to photograph, so that people can see what a counterfeit / re-marked salvage part looks like.
The photos and details are posted on the other related thread here: Bf862 purchased on ebay - labeled as 2AW2?
Yes, I cross-posted to a second thread on this topic, hoping to increase exposure of this issue. It is a sad situation, but I think it's important to raise awareness and help prevent more people getting burned.
If anyone does know of a reliable source for genuine "NOS" BF862, I am still looking to purchase a handful. Please PM me.
In the meantime, I'll be looking for current-production alternatives which can be sourced from the Tier-1 vendors.
The photos and details are posted on the other related thread here: Bf862 purchased on ebay - labeled as 2AW2?
Yes, I cross-posted to a second thread on this topic, hoping to increase exposure of this issue. It is a sad situation, but I think it's important to raise awareness and help prevent more people getting burned.
If anyone does know of a reliable source for genuine "NOS" BF862, I am still looking to purchase a handful. Please PM me.
In the meantime, I'll be looking for current-production alternatives which can be sourced from the Tier-1 vendors.
Sad indeed. Is it even worth faking them? Who would be interested – maybe a few hobbyists?
A fine sounding JFET. I have them running in my Pass B1 Buffer, PCA headamp and AKSA Lender preamp.
I might have a few (less than 10 probably) left. Will check this weekend and send a PM.
All BF862 for sale on those sites are fake. From China with love, original. 
The fact that someone recommends and says they are good can be considered a joke. 🙂
Only old stocks can be considered.
The fact that someone recommends and says they are good can be considered a joke. 🙂
Only old stocks can be considered.
New Toshiba 2sk209 GR or BL can be used but will require slight readjustment of resistor values.
I still have a roll of NOS of BF862 from 5 years ago. Maybe 50 left... and a handful of pairs that I matched years ago.
LD1014D’s however, are genuine and a deal still. Links over in LU1014D GB thread.
I still have a roll of NOS of BF862 from 5 years ago. Maybe 50 left... and a handful of pairs that I matched years ago.
LD1014D’s however, are genuine and a deal still. Links over in LU1014D GB thread.