[ARC5] "Re-Banding" SCR-274N

[Dennis Monticelli]

Michael,

I did read the first article you sent. Thank you.  It was from 1947 and
well written.  I did not find any contradictory statements to what I was
proposing.  Most of the article was on explaining freq multiplication and
and how it could be optimized in a tube via shaping the drive in order to
encourage harmonic generation.  Even so output power in doubling is usually
well below what you can get at the fundamental; we all know that.  There
was just one paragraph on multiple tube arrangements and it was stated that
power was indeed doubled when a single tube was joined by another tube in a
push-push arrangement.  This is conditional upon having adequate drive for
the second tube.  In the ARC-5 there is already drive power for two tubes.

So I think the drive re-wiring trick would work, though as Dave noted
you're not done yet.  There is still the PA tank to consider that is
invasive.

Dennis AE6C


On Wed, Mar 26, 2014 at 7:32 AM, Michael <k3mxo.hi at gmail.com> wrote:

> Check out http://jlandrigan.com/ and go to the article on frequency
> doublers
> and/or the one on frequency multipliers at http://www.qsl.net/va3iul/ .
> They explain it far better than I could.
>
>
>
> Best Regards,
>
>
>
> Michael, K3MXO, CBLA #6, BL01hx15np24 ... or there abouts
>
> Sometimes I pretend to be normal but it gets boring so I go back to being
> me.
>
>
> <blocked::blocked::blocked::blocked::
> http://www.nationalmssociety.org/chapte
> rs/NTH/index.aspx>
> http://www.nationalmssociety.org/chapters/NTH/index.aspx
>
>  <blocked::blocked::blocked::blocked::http://wh7hg.blogspot.com/>
> http://wh7hg.blogspot.com/
>
>
> <blocked::blocked::blocked::blocked::
> http://kludges-other-blog.blogspot.com/
> > http://kludges-other-blog.blogspot.com
>
> Hiki Nô!
>
>   _____
>
> From: Dennis Monticelli [mailto:dennis.monticelli at gmail.com]
> Sent: Tuesday, 25 March, 2014 17:36
> To: Michael
> Cc: ARC-5
> Subject: Re: [ARC5] "Re-Banding" SCR-274N
>
>
>
> Michael,
>
>
>
> Why would one end up with half the power?   There is a center-tapped
> secondary on the osc coil.  One half drives the paralleled grids of the
> 1625's, the other half drives the neutralizing cap, and the center tap
> develops the class C bias.  The mod would only require moving one of the
> grid wires to the neutralizing cap side of the secondary. The total drive
> power and the voltage drive level to each grid would remain the same.   The
> only difference is that instead of the 1625's summing their cathode pulses
> in the same phase of the osc cycle, each delivers its cathode pulse (of the
> same magnitude as before) twice per cycle.  Am I missing something?
>
>
>
> Dennis AE6C
>
>
>
> On Tue, Mar 25, 2014 at 8:16 PM, Michael <k3mxo.hi at gmail.com> wrote:
>
> -----Original Message-----
> From: arc5-bounces at mailman.qth.net [mailto:arc5-bounces at mailman.qth.net]
> On
> Behalf Of Dennis Monticelli
> > The best way to double is to move the secondary connections of the osc
> > transformer to drive the 1625's in push-push.  I've always wanted to try
> > that.
>
> This works however you also wind up with half the output power.  This is
> one
> of the disadvantages of a push-push doubler.
>
>
> Best Regards,
>
> Michael, K3MXO, CBLA #6, BL01hx15np24 ... or there abouts
> Sometimes I pretend to be normal but it gets boring so I go back to being
> me.
> http://www.nationalmssociety.org/chapters/NTH/index.aspx
> http://wh7hg.blogspot.com/
> http://kludges-other-blog.blogspot.com
> Hiki Nô!
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>