[sdiy] Tubin'

[Theo]

S/NC stands for [screen|shield] / no-connection.
Some tube types/brands use a unconnected pin to add a screening-grid/shield,
usually to be connected to ground.
This is mostly done in combination tubes to better separate both tube
halves.
Duno why there would be a shield in a single pentode.

HTH
Theo


----- Original Message -----
From: Pat Kammerer <spivkurl at wearerecords.com>
To: sdiy <synth-diy at dropmix.xs4all.nl>
Sent: Thursday, November 04, 2004 9:42 AM
Subject: [sdiy] Tubin'


> Well,
>
> I've been attempting to do some experimentation, and of course have come
up
> with a couple of questions.
>
> I'm working with a 6Y6G Pentode, and have found a datasheet here;
> http://hereford.ampr.org/cgi-bin/tube?tube=6Y6G
> I have very little experience with tubes, and I don't quite understand the
> base diagram.  I know which is which as for grids, plates, and heaters,
but
> what I don't understand is the pinout.  There is no pin at the sixth
> position, which I would expect, but there is one at the first position.
Can
> anyone tell me if there are any special considerations for pin 1? (I'm
> assume it's "Not Connected", but what does the S mean in S/NC?)
>
> Also, have any of you used a full wave voltage quadrupler to get a descent
> plate voltage?  I've tried and tried tonight with no luck.  The two books
> that I found schems in were both slightly different, but neither on gives
me
> an output.  Any other recommendations for a simple way to get
approximately
> 100 to 135 VDC from a 28V transformer?
>
> What will the consequences be of running the heater on about 4.7 VAC
instead
> of 6.3?  I'd be finding out for myself right now, if I could have gotten
> that quadrupler to work before getting to tired.  Oh well.
>
> Thanks for the help!
> Pat
>