John Curl's Blowtorch preamplifier part II

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I prefer the letter that Sir Archibald Clark Kerr wrote to Lord Reginald Pembroke.

Funny but not the same.

When Stalin gets the letter he wants to show it to everyone. So he steps into the hall, but it is empty, the street.. the same. Finally he wanders down to the square where a single fellow is scrubbing the streets. He shows him the letter to prove he has won the day. Then he asks "Where is everybody."

The street sweeper says " Comrade I am afraid that even with the progress we have made with socialism they are still at home secretly celebrating Christmas."

"And why are you here?"

"Well you see I used to be Jewish."

"And what do you think of the letter."

"Well comrade you must understand Trotsky also used to be Jewish."

"And how does that affect the letter?"

"Well you have to read it right." It really says "I was wrong!!!, you were right?"

(A joke better verbalized.)
 
Actually I have, much more polycarbonate than nylon. Before you cold form plastics you need to get the moisture content low enough so that you don't get bubbles.

Time and temperatures are the secret polycarbonate can dry in as little as 24 hours nylon takes 72. Never tried a vacuum.

As a quick beside and a thank you. I do some PVC molding using partial heating with halogen lamps. Bubbles are a recurring problem, even at what I measure to be way below the decomposition temperature of PVC. This must be it.

As a general question, I hope Stuart can shine his light on it: what are the water absortion qualities of PVC, and if it could be problematic heat forming in his way, how to dry it? I always assumed there would be a sort of O-Cl-F continuum with respect to water absortion, but perhaps I was wrong and this may solve a long harboured question.

vac
 
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Just double-checking, there will be a part two of "Low-noise Microphone Preamplifiers" in an upcoming Linear Audio ?


.

Sneak preview (only part of the contents of linear Audio Vol 3):

Circuit Design
A Headphone Buffer/Amp and Auto-EQ for Headphones - Richard Marsh
DIY Low-noise Microphone Preamplifiers, Part II – Scott Wurcer
Correcting transducer response with an inverse resonance filter – Steven van Raalte
Passive, Discrete, DC Coupled, Open Loop IV Converters - Sigurd Ruschkowski

jan
 
www.hifisonix.com
Joined 2003
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Sneak preview (only part of the contents of linear Audio Vol 3):

Circuit Design
A Headphone Buffer/Amp and Auto-EQ for Headphones - Richard Marsh
DIY Low-noise Microphone Preamplifiers, Part II – Scott Wurcer
Correcting transducer response with an inverse resonance filter – Steven van Raalte
Passive, Discrete, DC Coupled, Open Loop IV Converters - Sigurd Ruschkowski

jan

Would be REALLy great if I could buy your mags on line and pay with Visa!

PayPal does not work in my case.

:-(
 
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