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Primary Q




>     Secondly, I'm in URGENT need of some information if people
>would be able to help. Would those people that have access to an
>oscilloscope and signal generator please be able to measure the Q
>of their primary circuits and post the results directly to me?
[snip]
>    Please mail me the 3 frequencies. I am imploring people to help 
>me in this. Things I am trying to discover MAY have implications for 
>all our systems.
>
>Thankyou in advance.
>
>Yours in urgency,
>Malcolm
>
>
Here you are. I tried, but the Q is to high, and the F is to low for my SW
radio to recieve.

        13.125 turns    Fo = 6.9us              100K series R
                        Fh = 6.85us             My SW radio starts at 150K
and I cannot hear any
                        Fl = 6.95us             harmonics!

        13.125 turns    Fo = 6.9us              10K series R
                        Fh = 6.9us
                        Fl = 7.0us


        15.5 turns      Fo = 8.4us              10K series R
                        Fh = 8.35us     
                        Fl = 8.4us

 13.7nF cap 15.5 turns total 30 degree inverse conical coil 11.75" id. 31" od.

note: I had my RFI filter disconnected, it's to low a value. I'll wind some
of the 2" torroids tonight and try again tonight! When I measured the Q by
the decrementing cycle count, cycle 1: 2.5 volts, cycle 10: 1 volt. Period =
7.5us or 7.4us. Using Q=1/d d=ln((Ao/An)^1/n) = 9.8 and Req = 8.9 ohms. big
difference between the small signal Q=138 and the large signal Q=9.8!

I'm waiting with baited breath for you report!

Suggestion? (when done with current project)

                jim