ZM, In Aleph and other modulated current sources, a cap is need two pass copy of AC signal to CS. Is this necessary with transformers?
small signal xformers aren't made , usually , for passing any sort of DC ......... if they are , they aren't small no more 
so - regarding needs of biasing those bloody gates , xformer would see between 2V5-3V (depending what value of Rs Papa chose ) so ......... you can freely expect some cap in series with each secondary
that was the case always and always will be
we all know that Papa like Silmics and their sonic signature 😉 , so prepare ..... ok - you tell me which value is cunnin' to have there ?
as example of olde times - lookielookie (also as confirmation of Papa's words that amp is pure classic ) - so two pics of pure golden classics
on one of them you'll see clever way of avoiding caps ...... but that's also having some other penalties , so my - as always humble - thinking is that using cap is still most prominent way of doing it
so - regarding needs of biasing those bloody gates , xformer would see between 2V5-3V (depending what value of Rs Papa chose ) so ......... you can freely expect some cap in series with each secondary
that was the case always and always will be
we all know that Papa like Silmics and their sonic signature 😉 , so prepare ..... ok - you tell me which value is cunnin' to have there ?
as example of olde times - lookielookie (also as confirmation of Papa's words that amp is pure classic ) - so two pics of pure golden classics
on one of them you'll see clever way of avoiding caps ...... but that's also having some other penalties , so my - as always humble - thinking is that using cap is still most prominent way of doing it
Attachments
So small value resistors set bias, 400R resistor is local feedback setting gain, and cap does what? It seems to be pulling double duty?
don't look at that , as example worth here too much - currents are way too high for our case ...... due to less demanding control electrode ( base vs. gate ) we can make it more elegant
everything is , say , double duty there - small resistors are shunting secondary and biasing base of bjt in same time ; 400R is creeping current through small resistors , shunting secondary too
I posted that schm as example , where even feedback path is of same logic as in F6 (you can ignore Q13 in series with primary)
betchya that we'll find few more caps in F6, across pots in bias nets ; Papa seeded way too much simple machines around , and each of them is containing trick or two
puzzles , puzzles everywhere ........
everything is , say , double duty there - small resistors are shunting secondary and biasing base of bjt in same time ; 400R is creeping current through small resistors , shunting secondary too
I posted that schm as example , where even feedback path is of same logic as in F6 (you can ignore Q13 in series with primary)
betchya that we'll find few more caps in F6, across pots in bias nets ; Papa seeded way too much simple machines around , and each of them is containing trick or two
puzzles , puzzles everywhere ........
Shopping list so far.........SJEP120R100A SJEP120R100A - SEMISOUTH - TRANSISTOR, JFET, 1200V, TO-247 | Newark
JT-11-FLPCH
JENSEN TRANSFORMERS, INC. - PRODUCT PRICING
some toroids, some caps............
Regards,
Dan 😀
JT-11-FLPCH
JENSEN TRANSFORMERS, INC. - PRODUCT PRICING
some toroids, some caps............
Regards,
Dan 😀
well - I had impression previously - when he first time mentioned F6 - that he'll share that .
dunno - now , when you wrote that , I'm not sure - didn't asked ....... 😕
whatever - enough info is here , along with already shown bits and pieces how to bias SJEP in simple way
I'm excluded from game , too much of insider info , tnx to my resident spy in PL cousine 😡
dunno - now , when you wrote that , I'm not sure - didn't asked ....... 😕
whatever - enough info is here , along with already shown bits and pieces how to bias SJEP in simple way
I'm excluded from game , too much of insider info , tnx to my resident spy in PL cousine 😡
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Figured it might be like J2 and M2. Doing it is one thing, like Nelson is another. We both know he has some quirk thrown in there.
luckily , his quirks are heading to simplest possible solutions , lately
after deciding how to bias outputs , all one needs is to play with few variations for Rs , and few possible feedback amounts
I wouldn't choose M2-J2 biasing arrangement here ; it's possible with highish Rs , which I'll try to avoid
(just my opinion , not result of spy cam capture , situated in FW facility
)
after deciding how to bias outputs , all one needs is to play with few variations for Rs , and few possible feedback amounts
I wouldn't choose M2-J2 biasing arrangement here ; it's possible with highish Rs , which I'll try to avoid
(just my opinion , not result of spy cam capture , situated in FW facility
)