Thank you for the report on my beacon transmission.
This experiment all came to a sorry end , just after I ended the test on
Saturday afternoon. I had been using a 12 volt supply for the rig and had
adjusted the tapes right down the base loading coil to get the correct input
match. However, I normally use 50 to 70 volts on the Mosfets. Yes , you
guessed it.... I reconnected the 70 volts supply, pressed the key, had a
good lash at tuning the variometer and knocked the stuffing out of the rig,
to the extent that, not alone did the Mosfets die a terrible death, but two
chips, and the complementary driving transistors were zapped. I should have
re-adjusted the tap right up the coil before this hasty act.
The only thing still working was the oscillator. An hour later, it was all
operational again and a quick air test with G3KEV put my mind at rest.
These high voltage Mosfet rigs don't take prisoners......ouch.
Glad my signal made it as far as your qth, must try some experiments, with
and without the tuned counterpoise to see if it makes any noticeble
difference 'on air'.
73 Finbar EI0CF
-----Original Message-----
From: Des Kostryca <[email protected]>
To: RSGB LF_Group <[email protected]>
Date: 30 October 1999 22:53
Subject: LF: Beacon.
Finbar and the group,
Your beacon was heard in Gainsborough, 18 miles north of Lincoln (IO93OJ)
Friday morning at 07:15 on 137.5 kHz with RST 439 to 449. Was able to copy
the beacon well all morning till about 14:35 when local qrm made copy
difficult. I had been using a 10 mtr vertical with top loading but when
copy
became bad I switched to my 40 square mtr single turn loop (pointing
North/South) and your beacon was back with an RST of 459 and well above the
local qrm.
I had been working in the shack all morning and most of the afternoon
listening to 137 kHz but your beacon could be heard in the background
thanks
to my 500 Hz "barn door" IF filter. Funny thing is....I can still hear the
beacon with the rig switched off :-) Must be over exposure to cw.
73's all,
Des.
Des Kostryca (M0AYF) G.Q.R.P. no. 9788
I.A.R.U. loc. IO93OJ W.A.B. SK89
Member of the N.B.T.V.A.
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