Matched Jfets?
Any word on when a jfet kit will be back in stock, or ideas about how to get them? - Excited to get this project done.
Any word on when a jfet kit will be back in stock, or ideas about how to get them? - Excited to get this project done.
Parts in Europe
To the European F-5 builders: How did you source the JFETs / parts that have to be matched?
Ordering everything from the US (diyaudio and/or punkydawgs) gets prohibitively expensive once you add shipping + tariffs + VAT + handling fee.
My plan was to order the boards from diyaudio and source the other components locally, but I'm struggling a bit to find the correct parts.
To the European F-5 builders: How did you source the JFETs / parts that have to be matched?
Ordering everything from the US (diyaudio and/or punkydawgs) gets prohibitively expensive once you add shipping + tariffs + VAT + handling fee.
My plan was to order the boards from diyaudio and source the other components locally, but I'm struggling a bit to find the correct parts.
Just an FYI, there has been some progress on the JFET front and we are currently expecting to have matched pairs in the store in around 30 days time from today.
Awesome! Thanks Jason. Will you send out notifications via the email notification link on the product page? Is that the quickest way to know they are available?
Help! Instead of buying a matched set of (2) 170s and (2) 74s from Punkydawg, I apparently ordered a matched set of (4) 74s by accident. So if I buy a matched set of (4) 170s can I use them with the 74s I already have or do the 74s need to be matched to the 170s to work correctly in the F5?
Buying a quad of 170s is probably not going to work. Return them and get the right thing.
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Already ordered the correct pairs.
Any builds I could use the matched 74s for rather than returning them? Could be a good excuse to build something else!
Any builds I could use the matched 74s for rather than returning them? Could be a good excuse to build something else!
The store will have them again. Also, it's not that hard to do it yourself...
http://www.firstwatt.com/pdf/art_matching.pdf
Transistor matching
http://www.firstwatt.com/pdf/art_matching.pdf
Transistor matching
Is your question : what has to be paired ?
One 74s with one 170s ?
Or, one 74s with one 74s , idem for the 170s ?
In others words , pairs have to be made by board or by jfet types ?
I guess it is by types but I would appreciate someone make it clear.
This is what I got for matched FETs. I guess you can assume they all need to be matched to each other looking at the numbers and the fact the N and P are in their own bags. Not a P/N combination in each bag. I am NO expert on this though. I am a simple assembler working hard to understand the what/why behind all this black magic while trying to keep the smoke in.
Attachments
So you confirm my thought, thanks.
Personnally I would try to keep the smoke out 😀
No. The smoke comes pre-installed. There is only a problem when you see it leak out. Believe me... I R A expert.
The waiting for the Italians to get back to work and ship me my Chassis is killing me. It's all I need to finish the F5. I work for a very large corporation based in Germany. I think the entire company should be on the same vacation schedule and I vote for theirs. Only fair, right?
The waiting for the Italians to get back to work and ship me my Chassis is killing me. It's all I need to finish the F5. I work for a very large corporation based in Germany. I think the entire company should be on the same vacation schedule and I vote for theirs. Only fair, right?
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