Saturday, September 8, 2012

G0GSF versus G5RV - Part 1

Well, I am trying out the ZS6BKW.  I analyzed the G5RV prior to installing the new antenna so I can do a head to head comparison. The setup uses 92 feet of 16 gauge insulated copper wire as the main radiator and 39.5 feet of Wireman 551 window line and a W2DU ferrite bead choke between the window line and coax.   The antenna is suspended 45 feet above ground level in an inverted V configuration.  Here are some figures (on SWR) for comparison - the first column is the start of CW, the second frequency is the start of the phone portion of the band and the last is the end of the phone portion of the band:










350036004000





80m3.76>10G0GSF

2.42.79>10G5RV










40m700071257300






1.11.63G0GSF. 

3.532.5G5RV










30m1010010150







>10>10
G0GSF



55
G5RV










20m140001415014350






1.522.73G0GSF


1.891.842G5RV











17m180681810018168






2.52.743G0GSF

4.84.44.3G5RV












15m210002120021450






3.13.55G0GSF



4.54.755G5RV










12m248902493024990






2.62.93.1G0GSF


2.22.32.5G5RV












10m280002830029700






2.751.55.3G0GSF



3.33.754.2G5RV













Here are the consequences with the new set-up: (Note I use G0GSF and ZS6BKW interchangeably)



















(1) Using a tuner, 80m in the CW portion of the band is easily done.   The phone portion needs a wide range tuner.  The Palstar roller inductors do quite well and so do the Elecraft tuners KAT100 and the internal tuner in the KX3.   .












(2) 40m is now more efficient.  Considering that this is my bread and butter band, this is a good thing.

















(3) 30m is not usable at all.  Considering how important 30m is for DX work, this means I need a dedicated dipole














(4) 20m  -  In either the G5RV or the ZS6BKW - this band does not need a tuner.  Although the ZS6 is a little bit more efficient on the lower part of the CW band.
















(5)  17m is now much more efficient













(6)  15m is usable with a tap at 31 ft - best SWR about 3:1.  Careful though need to connect a  balun there and disconnect the coax from lower balun.


















(7)  12m - Both antennas are good on 12m












(8)  10m - The ZS6BKW is more efficient than the G5RV in this band