Not really, 4 must be enough
As long as I can make all the funny stuff with them, I'll be happy Luckily enough, they still want to go fishing with the old man Or snorkling for that matter, I did put them through a lot of lifes great stuff Here is a shot of my two oldest, diving in the adriatic sea Its a bit OT, but still a little bit fishy Actually they harpuned loads of Sepia octopussy (not sure of the name) that we barbecued in the evenings.But if the young guys dont want to play with the old man anymore, I might consider one more.......
Steen
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Now the thread has turned from fish to jfet voltage, I was wondering if anyone have tried cheaper/easier to get jfets?
What is the transconductance requirement for babbling? A good (high idss) pair 2n5462 should be possible to get, but the transconductance is only 2-8mS whilst the 2sj109 and 2sj74 claim to have 22mS typically... what would be lost in this circuit with the low transconductance?
(The 2n5462 can work with higher voltages).
The 2sj108 which papa uses for F4 offers good transconductance but 5V less than 2sj109, so it would be working in the red zone in a babbelfish...
How about wiring a couple of 2n5462 in parallel?
What is the transconductance requirement for babbling? A good (high idss) pair 2n5462 should be possible to get, but the transconductance is only 2-8mS whilst the 2sj109 and 2sj74 claim to have 22mS typically... what would be lost in this circuit with the low transconductance?
(The 2n5462 can work with higher voltages).
The 2sj108 which papa uses for F4 offers good transconductance but 5V less than 2sj109, so it would be working in the red zone in a babbelfish...
How about wiring a couple of 2n5462 in parallel?
cviller said:
I'm working something on that ........finding easy solution ,or sub.....eevn in case that you must buy -say-100 pieces for 30-40 Euros,and match them ....you can always find good use for several matched pairs or whatever . but I can't promise that I'll have my final conclusions faster than a month
even two jfets -meaning two pairs instead of one SJ 109 isn't wrong solution ; in toob world you can often find two triode systems within one envelope paralleled
You might have confused me with all your tubes... is this what you are talking about?
At least that was what I was referring to.
I won't hold my breath for you to finish the development, but I'm planning on making something fishy again, so if you have some initial conclusions or completely subjective impressions I would love to hear them!
At least that was what I was referring to.
I won't hold my breath for you to finish the development, but I'm planning on making something fishy again, so if you have some initial conclusions or completely subjective impressions I would love to hear them!
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cviller said:
magura just can't think in so tiny boundaries
yes-Pearl is good example
regarding my developing-I meant just on finding locally available jfet types and testing it ,nothing more...............
just go for it and try
point is that you can find cheap jfets useful for "our" purpose and buy it in lot ...............for matching and further playing
Having seen some of his stuff, the guy has no boundaries at all
He has CNC machines and uses them to great effect. But you have to work out how things should look like too, and he does that also! Very nice stuff, maybe a little biggishRegarding the J-fets, I dont think its unconditionally wise to use the cheapo's. It has often been said that for audio purposes, the Toshiba's rule. One way around the J-fet problem would be if we stick our heads together and invest in 1000 pcs of the 2sk370 and 2sj108 wich is still available from Toshiba. Any interest?
Steen
steenoe said:
Having seen some of his stuff, the guy has no boundaries at all
If I had a CNC machine I think I would make big stuff too!
steenoe said:
I'm very curious how papa is using the jfets in aleph j, but in babbelfish, I think you need every volt accepted by 2sj109. The 2sj108 only withstands 25V, so you don't have much headroom...
For other configurations however, I think they would be great!
steenoe said:
Having seen some of his stuff, the guy has no boundaries at all
Regarding the J-fets, I dont think its unconditionally wise to use the cheapo's. It has often been said that for audio purposes, the Toshiba's rule. One way around the J-fet problem would be if we stick our heads together and invest in 1000 pcs of the 2sk370 and 2sj108 wich is still available from Toshiba. Any interest?
Steen
magura:
man with very ugly gadgets
ugly skills
and ugly feel for ugly ;
you know that I saw his stuff , so you really must not defend him from me;that was just a joke.............as almost everything I write,wrote,will write.............
one thing: I'm almost machine engineer (proper naming?) , so I really know how big his skills and passion are.......at least looking at pics.
regarding cheapies...I agree and disagree ;concept and implementation is important ; parts are waaaaay less important,at least in Pass's territory of "simplest as you can but not simpler than....." and "good enough for purpose" ; this is second important thing I still learn from him..................just to find a way to blackmail him for adopt me.......
anyway.......have you any info about 108 and 370?
steenoe said:Nope, but I could get some info if needed
So the F4 is probably not the last thing that we will see with those little critters
Steen
humble me edited post you quoted.......
have you any other comment to my wise words?
hehe......
please-try to find that info.............they can't be xpensive in that quantity
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