4-500A's will have pins 2 & 4 commoned for the screen.
Note: The suppressor grid is connected to the base shell.
73 & Good morning
Marv WC6W
http://qsl.net/wc6w/
--- On Mon, 11/29/10, Carl <km1h@jeremy.mv.com> wrote:
> From: Carl <km1h@jeremy.mv.com>
> Subject: Re: [Amps] Help identifying tubes
> To: "mike stokes" <mike9v@gmail.com>, "Amps" <amps@contesting.com>, "Alek
> Petkovic" <vk6apk@bigpond.com>
> Date: Monday, November 29, 2010, 7:32 AM
> There better not be any continuity
> between any pins except the filament.
>
> If they are 5-500A pentodes, which seems most likely, they
> also work well in
> GG and better than a 4-400. Ive used Penta PL-175A's in a
> fully GG SB-220
> and they are as easy to drive as 3-500's.
>
> Carl
> KM1H
>
> ----- Original Message -----
> From: "Alek Petkovic" <vk6apk@bigpond.com>
> To: "mike stokes" <mike9v@gmail.com>;
> "Amps" <amps@contesting.com>
> Sent: Monday, November 29, 2010 3:15 AM
> Subject: Re: [Amps] Help identifying tubes
>
>
> > You should be able to tell with an ohm meter.
> >
> > The filament pins are easy to identify. They are the
> same for the
> > triode, tetrode and pentode.
> >
> > If it is a triode, the 3 other pins will have 0 Ohms
> between them
> > If it is a tetrode, only two of the other tree pins
> will show 0 Ohms
> > If it is a pentode, there will be no continuity
> between any of the
> > other three pins.
> >
> > From the pics, they look like 5-500 tubes but the Ohm
> meter should tell
> > you.
> >
> > 73, Alek
> > VK6APK
> >
> >
> > At 12:09 PM 29/11/2010, mike stokes wrote:
> >>Hi Guys
> >>
> >>Someone gave me 2 tubes years ago and said they
> were 3-500s. Well I am
> >>not
> >>sure they really knew, and I don't know as the
> lettering is worn off.
> >>Here
> >>is a link with some pics.
> >>
> >>http://picasaweb.google.com/mike9v/Tubes#
> >>
> >>The one on the left is an Eimac. It end in an
> A and has S4 7704
> >>stamped
> >>inside.
> >>
> >>The one on the right is a Westinghouse and looks
> like it says 5/5xxA where
> >>the x in worn and illegible.
> >>
> >>Any ideas on what these really are ? Or what
> is a good way to figure it
> >>out
> >>?
> >>
> >>Any help is appreciated.
> >>
> >>--
> >>Mike Stokes
> >>KK9V
> >>_______________________________________________
> >>Amps mailing list
> >>Amps@contesting.com
> >>http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> > http://www.qrz.com/db/vk6apk
> > http://www.qrz.com/db/vk6ap
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|