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----- Original Message -----
Sent: Saturday, August 12, 2006 4:37 PM
Subject: Fw: PA4VHF small backyard tests
----- Original Message -----
Sent: Saturday, August 12, 2006 4:33 PM
Subject: PA4VHF small backyard tests
Well, changed the antenna and fired up my little
teststation this afternoon in my backyard.
Antenna: 3 wires 7.5m long spaced 40cm each ,
vertical part about 6m long also 3 parallel wires spaced 40cm each.
Feed is about 2m from the far end.
Measured about 170pF and 60 Ohm (?) with bridge,
noisesource/136kHz oscillator and RX.
With variometer and loading coil connected, I
needed about 6,7mH to tune things, where I expected to find
around 8,0mH.
Somewhere I got around 30-40pF extra. Maybe
internal capacity of the loading coils???
With 100Watt DC-input I got about 200mA antenna
current sofar.
Remarkable: when switching TX on/off, I could hear
the first step-up transformer clicking (it's a 58mm 3C85 core)
is this usual???
The transmitter used is my little testbox with an
additional amplifier with IRFP360 running at around 12-14V, 6-9Amp.
Mal has heard me before with this transmitter
connected to a 15m spiral toploaded vertical..........
73
Dick, PA4VHF (JO32eg)
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