That is so last century - but I love it!
... almost as much as getting my hands on cheap genuine 2SJ74!
Cheers,
Nic
P.S. Now measure and draw one for each of your FETs
That is so last century - but I love it!
... almost as much as getting my hands on cheap genuine 2SJ74!
Cheers,
Nic
P.S. Now measure and draw one for each of your FETs
And who would pay for that?
Spent most of the bank holiday weekend rematching and that stage is finally all done now. Quite a task if anyone has tried matching 460 or so jfets!
The next step is to run some curve traces to prove they are genuine, my curve tracer should arrive Thursday. I have no reason to doubt they are Toshiba as I have made discrete opamps from these batches and no problems (they were purchased back in 2008 just as they were becoming rare which is, as I believe, before the rash of 'counterfets' anyway).
Then I will group them and PM people on the shortlist first.
There will be a restriction on the amount per person to help out as many as possible.
Will post results of curve tracer here but don't expect one per device!
The next step is to run some curve traces to prove they are genuine, my curve tracer should arrive Thursday. I have no reason to doubt they are Toshiba as I have made discrete opamps from these batches and no problems (they were purchased back in 2008 just as they were becoming rare which is, as I believe, before the rash of 'counterfets' anyway).
Then I will group them and PM people on the shortlist first.
There will be a restriction on the amount per person to help out as many as possible.
Will post results of curve tracer here but don't expect one per device!
Thanks. Those in my ??? marked bag are bogus indeed. Very good try but fake.
They lack the slant, the low Vgs responsiveness. Those things are in the datasheet curves also. When their Yfs(gfs) and Vgs(off) still shows good. Yours being a bit less for gfs should be our room temp diff right now. Most Northwest and Southeast Europe stretch.
They lack the slant, the low Vgs responsiveness. Those things are in the datasheet curves also. When their Yfs(gfs) and Vgs(off) still shows good. Yours being a bit less for gfs should be our room temp diff right now. Most Northwest and Southeast Europe stretch.
So, if this works, I made the mistake of putting the images in the body of the text.
I built a copy of Borbely Audio's mm/mc phonostage with Walt Jung super regs, very good but I don't use vinyl any more, I know..
Btw, Hannes (h_a) still has transistor sets for F5 builders which includes K170/J74 but he is away at the moment.
I built a copy of Borbely Audio's mm/mc phonostage with Walt Jung super regs, very good but I don't use vinyl any more, I know..
Btw, Hannes (h_a) still has transistor sets for F5 builders which includes K170/J74 but he is away at the moment.
Attachments
Price list
I have been through the shortlist now and here is the list of available sets.
Prices include PayPal charges.
P&P will be £5 to most countries.
All sets will be remeasured to avoid any potential errors.
Special matching requirements can be done within reason.
You can contact me at tony399@gmail.com
Cheers,
Tony
I have been through the shortlist now and here is the list of available sets.
Prices include PayPal charges.
P&P will be £5 to most countries.
All sets will be remeasured to avoid any potential errors.
Special matching requirements can be done within reason.
You can contact me at tony399@gmail.com
Cheers,
Tony
Marc,
I wasn't planning to sell the phonostage, it is still in prototype form and has a couple of niggles - runs a bit on the warm side and suffers from quite high dc drifting on mc due to front end jfets not being thermally coupled (even though there is an integrator circuit). It is quite useful for me to keep as the building blocks are discrete opamps which can be reconfigured for other uses if I decide or I can just rob the matched jfets from it.
MASantos,
The sets are in highlighted groups and the prices are per group. The amount of jfets per group varies and are priced according to overall tolerance and quantity, see the grid to the right of the spreadsheet for an overview. The sold sets are highlighted in a lighter colour with 'sold' next to them, I will update the list soon.
Cheers,
Tony
I wasn't planning to sell the phonostage, it is still in prototype form and has a couple of niggles - runs a bit on the warm side and suffers from quite high dc drifting on mc due to front end jfets not being thermally coupled (even though there is an integrator circuit). It is quite useful for me to keep as the building blocks are discrete opamps which can be reconfigured for other uses if I decide or I can just rob the matched jfets from it.
MASantos,
The sets are in highlighted groups and the prices are per group. The amount of jfets per group varies and are priced according to overall tolerance and quantity, see the grid to the right of the spreadsheet for an overview. The sold sets are highlighted in a lighter colour with 'sold' next to them, I will update the list soon.
Cheers,
Tony
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Thanks Tony for helping me get the Idss match on the jfets for my F5 with the 5Ohm EUVL degeneration trick you taught me. It seems to have worked beautifully, as this amp is as close to perfection as I can imagine. Certainly the best I have ever heard. Anyway, you went beyond all expectations as a seller and taught me a valuable trick, and I can't commend you highly enough!
Lucas
Lucas
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