I am assuming production is now over . Farnell now out of stock of just about everything
JFETs | Junction Gate FETs | Farnell United Kingdom | Results
Will the deliveries for the new products ever get there ?
316a
JFETs | Junction Gate FETs | Farnell United Kingdom | Results
Will the deliveries for the new products ever get there ?
316a
Now you're looking more clever by 10x - I didn't think that was possible...
There's not much information out there about any existing inventories.
Fortunately I made purchases for my own needs, but many DIYers are going
to have to substitute Mosfets parts in. This is not a huge problem, but the
SemiSouth R100 parts did have better overall performance.
There's not much information out there about any existing inventories.
Fortunately I made purchases for my own needs, but many DIYers are going
to have to substitute Mosfets parts in. This is not a huge problem, but the
SemiSouth R100 parts did have better overall performance.
I've been an occasional lurker here for a while and find this forum an inspiration at times
The Semisouth parts got me interested in solid state and a hybrid project I previously abandoned . Currently running a triode connected CCS loaded 4P1L driver and 200mH choke loaded R085 source follower . Given it the full 'tube' treatment with choke input , choke smoothed supply . I'm getting some very nice sounds and now want to build a duplicate amp with R100A . The low capacitance of these parts seems to almost be unique unless anyone else has some other suggestions for my application I do hope Teabag comes through 316A
@vdi_nenna
for fun I build my J2 clone also with IRFP240 on lower and upper position
the distortion was higher, the sound different,
you can say it in both ways, more veiled or more relaxed........ with a bit more body.
I could have lived with the Mosfet solution too, if I didn't have heard an original J2, that spoils... sorry to say it so often...... will be last time...!
for fun I build my J2 clone also with IRFP240 on lower and upper position
the distortion was higher, the sound different,
you can say it in both ways, more veiled or more relaxed........ with a bit more body.
I could have lived with the Mosfet solution too, if I didn't have heard an original J2, that spoils... sorry to say it so often...... will be last time...!
Last edited:
Semi South FET's
For any interested audio designers out there, franchised SemiSouth UK distributor Neutron LLP has a few SemiSouth SJEP120R063 devices still available to buy on first come basis. These parts are effectively 2 x SJEP120R100 in parallel in one package.
Contact : 01732 868646 email: sales@neutronltd.co.uk
Data sheet for SJEP120R063 is available for download on the SemiSouth web site which is still active as of date of this posting, otherwise can be obtained from Neutron.
Please note Neutron does NOT have any SJEP120R100 devices available.
For any interested audio designers out there, franchised SemiSouth UK distributor Neutron LLP has a few SemiSouth SJEP120R063 devices still available to buy on first come basis. These parts are effectively 2 x SJEP120R100 in parallel in one package.
Contact : 01732 868646 email: sales@neutronltd.co.uk
Data sheet for SJEP120R063 is available for download on the SemiSouth web site which is still active as of date of this posting, otherwise can be obtained from Neutron.
Please note Neutron does NOT have any SJEP120R100 devices available.
OK, so I set up a circuit to quick test one of the E120R10X that SemiSouthFan
sent me vs the R100 parts.
The stage was single-ended Common Source with no feedback driving 8 ohms.
The bias was a fixed 1.8 amps DC, and the Vgs was set for 20V Drain voltage.
The signal source was 600 ohms.
The Vgs of the R100 part was about 1.3V and the R10X was about 1.8V
Both exhibited nearly the same gain figures (~32 db) and bandwidth (see
resp curve below) and similar but not identical distortion numbers. (see
distortion curve below). Under these conditions, similar to the F6, the R10X
has generally lower distortion.
Two items of difference:
In the R10X I noted a higher Gate leakage figure of about 45 uA. Not a big
item, but something to allow for.
I also noted more drift in the R10X bias figure vs temperature, in fact I ended
up putting it in a simple control loop to stabilize it when running these curves.
In the F6, likely we would have DC degenerate or otherwise control the bias
current of the bottom device, which is of course not a big problem.
sent me vs the R100 parts.
The stage was single-ended Common Source with no feedback driving 8 ohms.
The bias was a fixed 1.8 amps DC, and the Vgs was set for 20V Drain voltage.
The signal source was 600 ohms.
The Vgs of the R100 part was about 1.3V and the R10X was about 1.8V
Both exhibited nearly the same gain figures (~32 db) and bandwidth (see
resp curve below) and similar but not identical distortion numbers. (see
distortion curve below). Under these conditions, similar to the F6, the R10X
has generally lower distortion.
Two items of difference:
In the R10X I noted a higher Gate leakage figure of about 45 uA. Not a big
item, but something to allow for.
I also noted more drift in the R10X bias figure vs temperature, in fact I ended
up putting it in a simple control loop to stabilize it when running these curves.
In the F6, likely we would have DC degenerate or otherwise control the bias
current of the bottom device, which is of course not a big problem.
Attachments
OK, so I set up a circuit to quick test one of the E120R10X that SemiSouthFan
sent me vs the R100 parts.
Thank you Nelson for taking a look at these parts. These parts are nominally identical to the R100 (same production line and design). They are R100 chips that sorted for threshold voltage about a quarter to a half volt higher than the R100 spec would allow. The SemiSouth engineering department had them packaged in TO247 to see what could be done with higher threshold parts in addition to the chips off these wafers that met the original SJEP120R100 spec.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.