Several people responded to my request for info on up to date dimensions
for the 204BA. My instruction book dates to 1965. A couple of people said
"leave it alone", but the definitive answer came from Roger Cox of Telex.
Roger provided a set of dimensions for stacking at 50 and 100 feet. He
also provided two tables which show the performance of the original
dimensions and the modified for stacking dimensions at different stacking
distances.
As it happens, the original dimensions appear to be good for the stacking
separation which I have chosen. (Based on multiple runs of YT.)
Rogers info is reproduced below.
George
w2vjn@rosenet.net
............................................................................
................................................
George,
Here is the YO file data for dimensions of 204BA's stacked at 100' and 50'
on the CW setting. This gives better F/B in a stacked configuration.
Hy-Gain 204BA (CW) stacked
14.000 14.100 14.200 MHz
4 elements, inches
4.0000 1.2500 1.1250 0.8750 0.6250 0.4375
0.000 3.6250 41.8750 46.0000 50.5000 24.0000 53.0000
122.875 3.6250 32.3750 46.0000 50.5000 24.0000 54.6250
211.625 3.6250 18.3750 46.0000 50.5000 24.0000 60.7500
307.250 3.6250 14.1250 46.0000 50.5000 24.0000 53.0000
73 Roger WB0DGF
Telex Communications, Inc.
George,
The 204STK dimensions were specifically for 100'/50'. The regular CW
dimensions (HG204BA1) look like they work just as well for a 105'/70'
stack. Here's how the two models perform:
HG204BA1 (CW-14.1):
Distance Gain(dBd) F/B(dB)
0 6.15 25.4
30' 8.41 23.8
35' 8.76 23.4
40' 9.07 20.3
45' 9.28 17.9
50' 9.36 17.3
55' 9.37 18.7
HG204STK (CW-14.1):
Distance Gain(dBd) F/B(dB)
0 6.26 23.6
30' 8.46 22.5
35' 8.82 22.0
40' 9.15 20.8
45' 9.38 20.4
50' 9.49 22.5
55' 9.51 22.1
73 Roger WB0DGF
Telex Communications, Inc.
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