--- In , "c1ferrari" >
>
>
> Happy New Year, all,
>
> Just wanted to report this article is unavailable on the web.
> When I re-discover, LOL, the info pertaining to power supplies -- I'll post.
>
> Best regards,
> Sam
>
> --- In , "c1ferrari" wrote:
> >
> >
> >
> > Hey Craig,
> >
> > Thanks for the reply! I'll see if I can get a link to the article with pics. I think Daniel had some
suggestions for the necessary power supplies.
> >
> > Next for your stable...Tek 570 or 370, Craig? ;-)
> >
> > Season's Greetings,
> >
> > Sam
> >
> > --- In , "Craig Sawyers" wrote:
> > >
> > > Interesting article, Sam.
> > >
> > >
> > >
> > > I have (surprise, surprise) got a 577 as well as a 575mod122C (and a regular
> > > 575 too).
> > >
> > >
> > >
> > > The key benefit of the 577 as compared with the much older 575 is that it
> > > was designed after the FET became common - hence the step amplifier on the
> > >
577 goes up to 2V per step as compared with 0.2V per step for the 575. It
> > > also (as the article points out) has a much wider range of voltage and
> > > higher current capability than the 575 - or the 570 for that matter.
> > >
> > >
> > >
> > > However, to be fully featured, it still needs a step amplifier to get to the
> > > 10V/step needed for some of the more esoteric (audio) valves like the 300B,
> > > and the characteristic curves for things like the KT88 call for 5V steps.
> > > And a screen grid supply is also needed whatever tracer is used. And
> > > although the formal definition gm is a limit (dIa/dVg at constant Va), and
> > > that most tube testers measure with a 1V grid voltage step, you can get a
> > > surprisingly accurate result by measuring between grid voltage steps and
> >
> doing the calculation on that basis. Or use the measurement method in the
> > > paper Sam attached, which should be as accurate as the calibration of the
> > > tracer.
> > >
> > >
> > >
> > > But (given screen grid and heater supplies) it is easier to do most small
> > > signal and some power tubes with a 577 as compared with a 575mod122C for
> > > sure.
> > >
> > >
> > >
> > > Craig
> > >
> > >
> > >
> > > PS it would be good to get a link to the article including the diagrams
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > From: [mailto:] On Behalf
> > > Of Sam Lucero
> > > Sent: 23 December 2011 02:33
> > > To:
> > > Subject: [TekScopes] Testing Vacuum Tubes with a Tektronix Model 576
> > > Semiconductor Curve Tracer... [1 Attachment]
> > >
> > >
> > >
> > > [Attachment(s) from Sam Lucero included below]
> > >
> > >
> > >
> > >
> > > manuscript courtesy of its
author, Daniel Schoo, is available, here, in pdf
> > > format. Please note photos have been omitted due to bandwidth requirement.
> > >
> > > Daniel furnishes the article on the condition it be distributed and
> > > reproduced with it's original content unchanged with no editing.
> > > An accompanying article on the Tek 577 appears with it.
> > >
> > > Enjoy and Happy Holidays!
> > >
> > > Sam
> > >
> > >
> > >
> > >
> > >
> > > Attachment(s) from Sam Lucero
> > >
> > > 1 of 1 File(s)
> > >
> > > <>
> > >
> > >
>
> > <
> > > es%20with%20a%20Tek%20Model%20576%20Semiconductor%20> Testing Vacuum Tubes
> > > with a Tek Model 576 Semiconductor Curve Tracer.pdf
> > >
> >
>
The links don't work. Am I missing something?
Anyone have input on Daniel Schoo's article on using Tek 576 to test tubes?
Glydeck