Stan,
Do you know what the resting Ep rating was for the stock L-4B? My L-7
run around 2500V, and I am wondering how much higher I can run that
before I start having to change tank components and the like. IOW, when
you substituted the HB supply, how much if any did you raise the plate
voltage?
73 de Mike, W4EF..........................................................
----- Original Message -----
From: "Stan Stockton" <k5go@alltel.net>
To: "Barry Kirkwood" <bjk@ihug.co.nz>
Cc: "Jason Cooper" <jbcooper@uswest.net>; <amps@contesting.com>
Sent: Wednesday, January 31, 2001 7:57 PM
Subject: Re: [AMPS] Additional Tube Brand Question
>
> Without question, replace the power supply with something a lot heavier
> and with more plate voltage than the original. Remember that it was
> designed when the legal limit was about 40% (1000W INPUT) of what it is
> now. However, if you run it at that level, it will probably last a long
> time. I had the original power supply in one catch on fire while a
> guest operator was working the Phone Sweepstakes Contest in about 1984.
> Now have HB supplies with about 3600V and the amplifier puts out 1500W
> with 100W or less drive. Good idea to put a muffin fan on the top
> cabinet above each tube blowing up. Otherwise, you can cook breakfast
> on the top cabinet.
>
>
>
>
> Barry Kirkwood wrote:
> >
> > I used an L-4B happily for years with the original parasitic
> > suppressors.
> > I added a reduction drive to the plate tune capacitor. I also built a
> > bigger and better power supply.
> > The L-4B was an excellent performer and I only quit it for a model
> > that had 160m capability.
> > 73
> > end
> > Barry Kirkwood PhD ZL1DD
> > Signal Hill Homestay
> > 66 Cory Road
> > Palm Beach
> > Waiheke Island 1240
> > NEW ZEALAND
> > www.waiheke.co.nz/signal.htm
> >
> > ----- Original Message -----
> > From: Jason Cooper
> > To: amps@contesting.com
> > Sent: Thursday, 01 February, 2001 8:59 AM
> > Subject: [AMPS] Additional Tube Brand Question
> >
> > Hi All,
> > I am about to re-tube my L-4B and have the same
> > question concerning the 3-500Z. In addition, what mods
> > are available for the L-4? I have read Measure's articles
> > on amps and agree with the soft start and the glitch
> > resistor. I plan to incorporate these when I
> > change tubes and am also interested in other mods available
> > for the L-4.
> > Thanks in advance,
> > Jason KN7AZ
>
>
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>
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