Amps
[Top] [All Lists]

Re: [Amps] Drake L4B

To: "R@contesting.com;Measures" <r@somis.org>,"Keith Dutson" <kdutson@sbcglobal.net>
Subject: Re: [Amps] Drake L4B
From: "Gary Smith" <wa6fgi@sbcglobal.net>
Reply-to: Gary Smith <wa6fgi@sbcglobal.net>
Date: Sat, 16 Jul 2005 14:31:40 -0700
List-post: <mailto:amps@contesting.com>
Are both tubes working? Sounds like one of the jugs is soft or has gone south.  
With 65-75 watts of drive the figures should be in the 7500 watt area
73,
Gary... wa6fgi
  ----- Original Message ----- 
  From: R@contesting.com;Measures 
  To: Keith Dutson 
  Cc: amps@contesting.com 
  Sent: Friday, July 15, 2005 1:07 PM
  Subject: Re: [Amps] Drake L4B



  On Jul 15, 2005, at 12:43 PM, Keith Dutson wrote:

  > Hi, am new to this list.
  >
  > I recently acquired a Drake L4B.  The previous owner said the amp had 
  > been
  > "refreshed" several years ago but not used for more than 2 years.  A 
  > friend
  > who has all Drake equipment looked it over and gave thumbs up to 
  > condition
  > of the unit.  The bandpass and power switches are tight and smooth.  
  > The fan
  > is quiet and in perfect shape.  The power supply has been rebuilt using
  > modern caps and solid state diodes.  Voltage output has not been 
  > measured.
  > Output in CW/Tune is about 540 watts as measured by an Alpha 4510 
  > wattmeter.
  > This seems low.  What should I look for?

  Input SWR of > 1.4:1 typically reduces the power delivered by a 
  solid-state exciter.  If the AØ anode / plate current is under 700mA, 
  not enough drive is arriving at the cathodes of the 3-500Zs.
  >
  > Thanks in advance for your advice.
  >
  > 73, Keith NM5G
  >
  > _______________________________________________
  > Amps mailing list
  > Amps@contesting.com
  > http://lists.contesting.com/mailman/listinfo/amps
  >
  >



  Rich Measures, 805.386.3734, AG6K, www.somis.org

  _______________________________________________
  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

<Prev in Thread] Current Thread [Next in Thread>