Hi everyone,
Thanks to Mr Pass for the sweet spot and ZM's comment on #2. I prepared 2 SE style schematic I plan to use the new SIT. Like most of us, I am still impatiently waiting for the release announcement, so both are still in drafting stage. No 2 should be nice and hot, hopefully not too hot so a 0.5 K/C HS will be enough. All comments are appreciated.
Thanks to Mr Pass for the sweet spot and ZM's comment on #2. I prepared 2 SE style schematic I plan to use the new SIT. Like most of us, I am still impatiently waiting for the release announcement, so both are still in drafting stage. No 2 should be nice and hot, hopefully not too hot so a 0.5 K/C HS will be enough. All comments are appreciated.
Attachments
Hi everyone,
Thanks to Mr Pass for the sweet spot and ZM's comment on #2. I prepared 2 SE style schematic I plan to use the new SIT. Like most of us, I am still impatiently waiting for the release announcement, so both are still in drafting stage. No 2 should be nice and hot, hopefully not too hot so a 0.5 K/C HS will be enough. All comments are appreciated.
I resume - on left sch - 22R as drain resistor for mosfet is typo ?
Wasnt Rome burned to the ground
Oh, no it still exits and I like it very much!
@new SITs from wakoo Chinese and exploring from PAPA….. many THX
what a big chance for us……I hope PAPA will not buy them all……
Nope, it's there to reduce OS dissipation and used as feedback point. Aside from efficiency issue, is there other problem?I resume - on left sch - 22R as drain resistor for mosfet is typo ?
Observing the curves at #7 and the chosen operating point of 55V, 30mA, drain current and -0.75V gate bias, seems 2 parallel sections of 6DJ8 could emulate the LCao SIT pretty closely. Looks like my circuit could be built a little sooner while waiting for the real stuff. I'm ordering the OT pair. Please comment if anybody see any serious flaw.
Thanks for the comments.
@buzzforb
Because a SiT is less microphonic, rugged for car use, no heater, maintain stable transconductance over time, and we greedy boyz like to follow Papa Pass. Also a DIYer can always hope that Lao Cao or his dealers will offer matched pairs, similar to LCao speaker offering.
@ZM
Off course, and the 6dj8 plate impedance will be higher by a factor of 4 compared to the SiT, but this way I'm hoping to be able to at least observe DC bias, OS thermal stability and miller effect of Crss, iron out issues on the inductor and OT while waiting.
@buzzforb
Because a SiT is less microphonic, rugged for car use, no heater, maintain stable transconductance over time, and we greedy boyz like to follow Papa Pass. Also a DIYer can always hope that Lao Cao or his dealers will offer matched pairs, similar to LCao speaker offering.
@ZM
Off course, and the 6dj8 plate impedance will be higher by a factor of 4 compared to the SiT, but this way I'm hoping to be able to at least observe DC bias, OS thermal stability and miller effect of Crss, iron out issues on the inductor and OT while waiting.
I have heard from LaoCao regarding the actual run of parts, and the curves
came out somewhat different than the prototype run. They are still nice
SITs, but it looks like potential designs will have to be adjusted for lower
transconductance and higher drain impedance.
I am waiting for a response to my request to buy some.
came out somewhat different than the prototype run. They are still nice
SITs, but it looks like potential designs will have to be adjusted for lower
transconductance and higher drain impedance.
I am waiting for a response to my request to buy some.
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