Before the blue boards, there was the green board

for the DIY ST35, the Dynakit and every other PP EL84

Before the blue boards, there was the green board

Postby EWBrown » Sat Aug 04, 2012 9:18 am

In the Beginning....


Image

There was the Rev - ST35 board.

Very similar to the Rev B, other than it did not have the 10 ohm cathode current measuring resistors.
My method was to simply adjust the "bias" pots so that the EL84 cathode socket pins (pin3) measured at
400 to 430 ohms relative to power/signal ground, andjust go with that.

There are not too many of these green boards in existence, I figured that it was time to share the pic.

/ed B
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Postby Shannon Parks » Sat Aug 04, 2012 11:36 am

I love those Nichicon power supply caps: 105C rated and low ESR. I think ten years ago I won an eBay auction of around 700 of those caps for $50. I still have a lot of them. (lol)

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Postby EWBrown » Sat Aug 04, 2012 4:44 pm

I still have a "boatload" of those Nichicon caps and CL-50s that you sent me years ago.

Then I found more , as well as a large qtyof 180 uF/500V caps, and other goodies at an NH "antique" (read that as "junque" or "thrift" shop.

/ed
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Re: Before the blue boards, there was the green board

Postby 20to20 » Sat Aug 04, 2012 8:01 pm

EWBrown wrote:My method was to simply adjust the "bias" pots so that the EL84 cathode socket pins (pin3) measured at
400 to 430 ohms relative to power/signal ground, andjust go with that.
/ed B


Ed... So casual back then....

(lol)

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Postby EWBrown » Mon Aug 06, 2012 7:04 am

They're just tubes, not NASA JPL Mars Rovers, fanatical precision isn't required ;) (lol) O:)

Curiosity has Landed! I wonder if it will find any evidence of ancient Martian tube technology :/ (???) ;) (lol) :))

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/ed B
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Postby 20to20 » Mon Aug 06, 2012 7:37 am

EWBrown wrote:
Curiosity has Landed! I wonder if it will find any evidence of ancient Martian tube technology
/ed B


What I want to know is where the heck is Friday?

That group hug at JPL went on a l-i-t-t-l-e too long this morning....

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