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From: Jim Barber, N7CXI
Date: 4/19/99
Time: 10:52:06 AM
Remote Name: 208.21.129.44
Hi Jack,
Jim Barber, N7CXI here.
Just FYI, I completed a "kitchen-table" CFA Sunday afternoon, and made a 400-mile SSB contact on 3920 Sunday evening.
Considering the house has foil-back insulation in the walls and ceiling, and the roof is 100% covered with flashing under the shingles, I consider that amazing!
Details -
CFA construction: Cardboard, tinfoil, per antenneX articles
Phasing network: L1 per (revised) article, L2 and L3 wound on T200-2 cores to save space. I built the network into the remains of a 300 watt MFJ tuner, may it rest in pieces.. :-)
Other: 2:1 VSWR bandwidth ~30kc, (75 meters) almost exactly per Ted's article. I need to use better feed-through's, and C1 needs more spacing, as the tiny MFJ cap will arc occasionally at 100 watts. Interesting to note, though, when the network is tuned for maximum field strength, only a *very* small amount of heat is detectable in the E-plate circuit at 100 watts.
I know you have other pictures, but I took a couple for just for posterity. I can email them in any format, if you're interested. (Originals at 300DPI)
Best 73, Jim Barber, N7CXI