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FETBloak/Bigbloak discrete op amp boards and parts

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jaygunn

Active member
Joined
Jul 19, 2006
Messages
38
Location
Chapel Hill NC
I bought the boards and parts for making my own discrete op amps, but didn't follow through. This 'kit' includes the following items:
-- schematics for the original and the revised FETbloak/BigBloak DOAs, by Tamas Kohalmi. There are several versions of the revised schematic, both use the same board, both are included. Only difference is replacement of the original R6 with a 1N5298 current-regulating diode. I do not have the diode in this package because I had been planning to make the R6 version.
-- (5) boards about 1" square for the revised version of the op amp, with gold plated pins
-- (4) each of MJE700G, MJE800G (Darlington transistors for the output), BC550C, BC560C complimentary transistors, BD139G, BD140G transistors (from the older version of the FETbloak, you probably won't use these
-- (20) 2SK170BL Toshiba low noise JFETs, extra so you can sort by specs,
-- (20) Mil Mix spare gold plated pins
-- (only 2) Black plastic 1" square op amp covers. You epoxy pot the completed op amp into these covers after testing.
Note that 2SK170BL JFETs are often now sold on eBay and other sources but are usually counterfeit. These were responsibly purchased in 2008 before these fake 2SK170s started to appear and not bought from China or on eBay. Foil protected, never opened, ready for sorting.
        The JFETs go for $1-8 now. The boards are unavailable. I am selling the entire kit for $34 and I'll pay the shipping within the 48 contiguous states. Paypal only.
FETbloak-parts-and-docs-1.jpg
FETbloak-parts-and-docs-2.jpg
 

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