well , it's sent
will forward Tracking No, via PM , as soon I get home
being as usual lost in space and time , I had Murphy arranged agony with delivery of cores , from german distributor .... getting them no less than in third attempt ..
after that I was really lost in frantic attempts to organize logistic and finish final and ultimate buffer iteration , discovering still actual Toshiba JFets - 2SK2145 .... but as always , slightly optimistic expectations are always too optimistic , so thing become too optimistic
I had intention to finish them and send instead of present version with Diamond buffers ....... because JFet version is , if not better in THD spectra (in fact they're pretty much the same)- certainly better behaving in output offset area , while allowing pretty much higher input impedance of buffer itself
so , mea culpa (maxima) , being a kiddoe while playing , loosing sense of time
in any way , as soon new pcbs with (presoldered) JFet buffers are done , will send them to you and few first boyz having Diamond Buffers, with no charge ..... with apology repeated
will forward Tracking No, via PM , as soon I get home
being as usual lost in space and time , I had Murphy arranged agony with delivery of cores , from german distributor .... getting them no less than in third attempt ..
after that I was really lost in frantic attempts to organize logistic and finish final and ultimate buffer iteration , discovering still actual Toshiba JFets - 2SK2145 .... but as always , slightly optimistic expectations are always too optimistic , so thing become too optimistic
I had intention to finish them and send instead of present version with Diamond buffers ....... because JFet version is , if not better in THD spectra (in fact they're pretty much the same)- certainly better behaving in output offset area , while allowing pretty much higher input impedance of buffer itself
so , mea culpa (maxima) , being a kiddoe while playing , loosing sense of time
in any way , as soon new pcbs with (presoldered) JFet buffers are done , will send them to you and few first boyz having Diamond Buffers, with no charge ..... with apology repeated
Attachments
and what's of 2SK170 ?
-they're available
-they're small
-they're cheap
-I intend to use 3 small critters in parallel , effectively 6 JFets in parallel , in each position (3 up, 3 down)
when you use 3+3 in same sex buffer , they're having same THD spectra as Toshiba complementary buffer , with even better loading capability , while having superior tempco behavior
-they're available
-they're small
-they're cheap
-I intend to use 3 small critters in parallel , effectively 6 JFets in parallel , in each position (3 up, 3 down)
when you use 3+3 in same sex buffer , they're having same THD spectra as Toshiba complementary buffer , with even better loading capability , while having superior tempco behavior
Nothing to be sorry of .....
Your behavior (and expectations ) is logical ....... while I'm logical and nested in reality approx. as Tom Sawyer ........ or my personal hero , picture attached.
Tr.No. is RR23682705RS ; soon to be visible on all international tracking sites.
I believe you'll receive new buffer boards before you start soldering DB ones
You can spend time working on chassis , taking in account dimensions form above posted screenshots.
DB pcbs you can use wherever you want , or you can cut them adequately, and have Good Gemini boards for something else
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Lucky (read -notworthy) ZM
I had my own Schwäbische Omama when I was small ....... and now I have my own Schwäbische Bruder
as I wrote in several places , regarding J309 , and that pretty much includes BF862 - those are parts having higher Idss , so when you want to use them in buffer in Toshiba style , source resistor needs to be of highish value , comparing to Toshiba parts ;
highish value of source resistor is directly increasing Rout of stage , so no go
enclosed schm of buffer stage ..... just as reminder that there is no free lunch here ..... if you want both simplicity and performance , no way around ......
I'm satisfied with DB buffer , but this one is simpler to make , with few benefits more
highish value of source resistor is directly increasing Rout of stage , so no go
enclosed schm of buffer stage ..... just as reminder that there is no free lunch here ..... if you want both simplicity and performance , no way around ......
I'm satisfied with DB buffer , but this one is simpler to make , with few benefits more
Attachments
Dear Zen Mod:
Check the connection mapping when you get it - I had a wrong connection in the intermediate layer in mine, and had to cut the two PCBs apart and solder new leads to the headers ...
Best regards, Claas
