Does the front end :
-with jfets
-w/o jfets (caps only)
-tube front end
-input transformer
of singing bush will affect the measurement?
-with jfets
-w/o jfets (caps only)
-tube front end
-input transformer
of singing bush will affect the measurement?
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point is - as long you're having enough cojones to drive that big honkiing gate , there will be no problem
SIT doesn't care of which you made those cojones
so . preceding stage with low enough impedance , and you're good
watch Papa's BAF 2015 Lecture ( link in first post) and I believe there are some graphs
...... if that's what you were asking
SIT doesn't care of which you made those cojones
so . preceding stage with low enough impedance , and you're good
watch Papa's BAF 2015 Lecture ( link in first post) and I believe there are some graphs
...... if that's what you were asking
You need some iron. 16/8/4 impedance matching transformer could be the missing ticket for slightly less rosy like the 859. 😀
I know that ........ even choke loading , with carefully chosen rail and Iq , can be effective enough
though, not easy task of finding choke available everywhere , let alone output xformer
that 3A2 Iq figure was/is sooooo tempting , but pretty big bite to swallow ,going xformer route , not that much easier even decreased to 2A2
though, not easy task of finding choke available everywhere , let alone output xformer
that 3A2 Iq figure was/is sooooo tempting , but pretty big bite to swallow ,going xformer route , not that much easier even decreased to 2A2
I mean an addition of impedance matching transformer at the output without changing the circuit. An autoformer should do, I'd use the 18+18V secondary of a Plitron for testing. The THD spectra clearly indicates zout being a tad high for 8 ohm. If the result sounds good then may increase supply to 90V and reduce Iq to 2.3A.
ok i've seen the lecture.
i saw at articles nutube preamp has 140ohm to 170ohm output impedance.
is that low enough to drive hockey puck sit input without any buffer?
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short 220R at NuToob output and situation is much better
not ideal , in my book , but much better
not ideal , in my book , but much better
aha , in form of patch
yup , valid idea 158%
they even had a product , intended for OTL Lovers , called Zeroformer
they sang accolades , but somehow I had impression that plain Donut was wound as autoformer , without any special materials
Pa and Bob, they know each other for long time
and Bob was for considerable time one of Honchos of some Cyclotron ("some" - I was told, but too old to start remembering things now)
and Bob was for considerable time one of Honchos of some Cyclotron ("some" - I was told, but too old to start remembering things now)
I am getting too old to remember tose days but that is how I met Nelson and Kent English
continuing
Meeting nelson and Kent thankfully changed me from a tube guy (all power supplies and amplifiers at the cyclotron are tube based) to a hard core follower of this forum 😀 - how else could I have met you great guys and enjoyed all the BAFs
One reference only because really this thread isn't about me
Cyclotron - Crocker Nuclear Laboratory :: Home
Meeting nelson and Kent thankfully changed me from a tube guy (all power supplies and amplifiers at the cyclotron are tube based) to a hard core follower of this forum 😀 - how else could I have met you great guys and enjoyed all the BAFs
One reference only because really this thread isn't about me
Cyclotron - Crocker Nuclear Laboratory :: Home
these multilegged fuses are for Sissies , not brave enough to mess with 1KV+ toobz
you still have time to revert back , from Sissy side , to proper Dark one
you still have time to revert back , from Sissy side , to proper Dark one
There is something to be said about the Dark Side
As I recall cyclotron at max output could draw power equal to the rest of campus
As I recall cyclotron at max output could draw power equal to the rest of campus
Wow...that's a lot of power; thanks for the tidbit.
(I now have this image of Kent turning a knob and all the lights dim on the campus. 🙂 )
(I now have this image of Kent turning a knob and all the lights dim on the campus. 🙂 )
