OT100/8005

If they glow, this is the place to be
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Cressy Snr
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#1 OT100/8005

Post by Cressy Snr »

Managed to pick up a pair of these babies for £58 off ebay.

They were used in the Macintosh M1 series of amplifiers in the '50s.

Image

This particular pair were made in the 70s by Tungsram.

Here are the curves:

http://frank.pocnet.net/sheets/049/8/8005.pdf

I feel a transmitter amp coming on :)

Ideas for an op point would be welcome.

Transformer drive with zero bias might be nice looking at the curves.

Steve
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pre65
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#2

Post by pre65 »

Nice one Steve. :wink:

I knew you wouldn't be "resting" for very long. :lol: :lol:
The only thing necessary for the triumph of evil is for good men to do nothing.

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Mike H
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#3

Post by Mike H »

Bluddy hell over 1 Amp.

May need a lot of grid driving for A2 though, check out the grid milliamperes graph :D



 
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
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Mike H
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#4 Re: OT100/8005

Post by Mike H »

SteveTheShadow wrote:Ideas for an op point would be welcome.

Transformer drive with zero bias might be nice looking at the curves.
Maybe 450V, 50mA, 0 bias?

Or, 450V, 100mA, +10V bias. Looks like needs about 10mA for the grid if it goes to +20V



 
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
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