[3830] W7WHY SO/AB/HP (kinda long)

Tom Osborne w7why at mail.coos.or.us
Mon Dec 1 03:24:57 EST 1997

                   CQ WORLD WIDE DX CONTEST  1997

      Call: W7WHY                    Country:  United States 
      Mode: CW                       Category: Single Assisted HP


      160        3        7     2.33      2       2  Inverted L
       80       11       24     2.18      8       7  Dipole @ 90 feet
       40       83      222     2.67     23      39  3 phased verticals
       20      263      744     2.83     29      82  Home-brew 3 el. mono.
       15      123      304     2.47     22      48  2 el delta loop fixed E.
       10       36       85     2.36     13      16  2 el delta loop fixed E.

     Totals    519     1386     2.67     97     194  =>  403,326

              Total Hours: 19.5

Equipment Description: FT-840  FL-2100B (500 watts)   MFJ 784-B DSP Filter

Contest Team: Neigers Tigers

Club Affiliation: Southern Oregon DX Association 


Well, what a weekend.  Conditions on the higher bands were great.  I was 
disappionted in 80.  Didn't hear that much here.  40 was hot Friday night.
It was best I have heard in years here. Worked so many Eu. stations I thought
I was on the East coast. Not as good Sat nite tho'.  Where was everyone on
160?  It was open. I worked KH7R and KL7Y and some VE's, but no activity.

I got the new Svetlana tubes Thursday and thought I would put them in the
amplifier for the contest.  Took the FL-2100B apart, and installed the new
tubes, turned the heaters on for a while to warm them up.  I hit the foot 
switch to see how they were going to work, and immediately, got a WHAM-BANG,
 the ammeter pegged at 600 mils, and all kinds of smoke came boiling out.
I took it apart, and saw all kinds of black resistors.  I replaced the grid
resistors, the parasitic resistors, and one input capacitor.  Turned it back 
on and the same thing happened again. The FL-2100B just didn't like the 
Svetlana tubes.  So looked at the amp all in pieces and burned up and though
"man there goes the weekend!"  Turned the exciter on, and saw the pilot light
had decided to burn out.  Murphy came early.
I got up Friday and took another look at the amp and after getting done crying
decided to give it one more try.  Took all the bypass caps out (they looked hot),
Took the grid resistors out, the input RF choke, the parasitic chokes and 
threw them all in the garbage.  Replaced the 200 pf grid caps with 350 pf, 
wound new parasitic chokes, made a new input choke and replaced 2 tuned input
caps.  Turned it on, and help my breath, hit the foot switch, and all looked OK.
Let it warm up for a while and applied a little power.  30 watts in, 300 out.
So far, so good.  Let it warm up and gave it full power, and 1100 watts out
on 40.  I looked Murphy in the eye and he blinked.  Then I looked and the
pilot light had came back on by itself.  Anyway, by the time 0000 came around
every thing was ready to go and performed like clockwork all weekend.
The MFJ 784-B is a real performer in the QRM. Set it for about 150 cycles
and never hear the QRM.  That thing sure works good! 
Thanks for all the contacts and hope everyone had as much 
fun as I did.  73 and see you in the 10 meter contest.

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