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FS: Paradise Phono PCB Set

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Hi. sq225917 already answered by private email, sorry for the delay. As I said was side track with a lot of other projects here locally, repaired, and Covid related delay in our day to day. Everything now take so long...

Anyway started the JFET test and matching for the Calvin sets. Here getting prepare for curve tracer testing of all 200 PF5102 JFET. Then I'll double check on my own Calvin pcb.
Long work ahead of me...
Stay tuned
SB
 

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  • Calvin Transistor Matching.jpg
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I compared the both matching methods (with curve tracer and the suggested test gig as included with the docs), and both gives similar results. I already have matched sets and the zero output adjustment is rock steady and easy to adjust. I should be able to ship the remaining Calvin pcb with matched transistor sets by the end of the week.

Since I tested them in the actual circuit, with the actual pcb, you should be able to get exactly the same result as me...

BTW while I assembled a test pcb to check the parts matching I realized that the pcb silkscreen for R1 & R2 is incorrect, and should be reversed. The circuit will still work as it is since both 100R & 75R resistors are so close in value, but it is better to assemble the pcb according to the schematic. Sorry for that... See the included correction.

Stay tuned for updates.
SB
 

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  • Calvin test pcb.jpg
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  • Calvin Silkscreen error.JPG
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