[Top] [All Lists]

Re: [Amps] [Fwd: Re: LK 500 ZA heat]

To: "alexander a. aimette" <>, <AMPS@CONTESTING.COM>
Subject: Re: [Amps] [Fwd: Re: LK 500 ZA heat]
From: "jeremy-ca" <>
Date: Tue, 14 Aug 2007 22:16:39 -0400
List-post: <>
> 1-These amps are notorious for  parasitics.  EVERY ONE  OF MY AMPS WAS
> FITTED OUT WITH  the Ralph Measures 3-500z   parasitic suppressers

You just said two very dirty words, Tom will now proceed to try and castrate 

BTW, my LK500ZC has many many hours behind it including several ARRL and CQ 
DX and WPX contest awards. I never once had a "parasitic" problem or lost a 
tube since it was new in 1987. It has also tuned just fine into 3:1 and 
higher VSWR.


and I
> had  no further problems--for 10 years, in every cqww and arrl test
> during those years. I replaced just two 3-500z tubes in all that time.
> 2-Some of these amps have a low and a high fan setting.  I always used
> the high fan setting.  There is also a temp sensing circuit which
> switches the fan to a high setting with a higher duty cycle.  If this
> cicuit is not working that may be your problem..
> 3-The amps I had all were fitted with four fans in a wall behind the
> tubes.  Check that they all work.  Also note that the fans are usually
> very, very  noisy on the high setting.  If the fan noise is very quiet,
> then  the fans are NOT working at the high rpm setting.
> 4-If you are running the amp at the 3500 dc high volt tap instead of the
> 3100v tap on the xfmr(just switch to the high voltage indication on the
> front panel, no load) you will have tuning capacitor arcing and
> bandswitch arcing problems on any load other than 1:1 SWR.  This amp is
> not designed to operate  at power levels  of 1500w at other than 1:1.
> My amps ran well at 1200watts into loads up to 1:3 SWR..    I ran all
> of my amps at 1200-1300w MAX into low swr loads for years  at v47kp
> without problems.
> If you insist on getting 1500w out, good luck!!
> 5-Drive power was limited to that which gave 1200w out, typically 70-100
> watts depending on the band.
> 6-I never ran the amp with the full  break in system.
> alex aimette, w2ox/v47kp
> _______________________________________________
> Amps mailing list

Amps mailing list

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