[AMPS] Amp Supply LK500ZA cooling? mods?

[Rich Measures]

>Greetings.
>I searched the archives (by Subject field) and didn't find anything
>about the Amp Supply LK500ZA.  I purchased this amp Saturday from a
>dealer at a swapfest for $600.  The main reason I got it was to have
>something for 160M, which my L4 doesn't cover. 

The fixed padder capacitors in the LK500 tank are not designed to handle 
RF current.  

>It is putting out about
>1100 watts on CW, which is fine with me.  However, it sure does seem to
>me to be running hot.  The cabinet gets very hot very quickly.  I have
>been in the habit of placing a 5" muffin fan (exhausting upward) on top
>of the cabinet (over the tubes) of various gear in the past (S-line,
>30L1, SB200, Warrior, etc) and that always made the cabinets quite cool,
>but it is helping little if any in this case.  There doesn't seem to be
>a lot of airflow coming out the side of the cabinet, either, although I
>can hear the internal muffin fan running.  Has anyone else had this
>experience with this amp?  I just wonder if the internal fan may need to
>be replaced. 
>
I repaired one that suffered from intermittent parasitic arcing.  The 
ball bearings in the internal fan had flat spots.  

>Also, are there any mods documented anywhere for this amp?  

I have not seen an article on the LK500.

>I don't
>intend to rebuild it or do anything major, but if there are any major
>design flaws that are simple to fix, or anything to watch out for, I
>would like to know.  

Better parasitic suppressors, glitch protection and high-speed switching 
are the only mods I know about.  

>I will mostly be using the amp for DXing plus
>occasional contesting, though I will drop the power a bit for any
>extended duty cycling.   (The amp does not have the QSK or external
>Hypersil transformer options).  Also, does anyone have a manual that
>they might be able to copy a few pages of for me?  I got a copy of a
>manual with it, but after getting it home I notice that there are some
>pages missing.  Thanks!
>
You probably need a copy of the diagram.  The rest is of lesser value.  
Rich---

R. L. Measures, 805-386-3734, AG6K   


--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm