144 MHz yagis
- this page was revised to include April 2010 G/T data -

Date: Tue, 16 Apr 1996 09:05:42 
From: Jay Kesterson
Subject: Summary: 2m antenna info

Last week I posted the following note asking for info on 2m EME antennas.
Here is the promised summary of the data. Thanks to K2LME, N1BWT, NC7K,
VE7BQH and SM7SJR. VE7BQH supplied a lot of data including his latest
antenna gain chart from DUBUS.

 I wrote:
 > 1. Cushcraft 17B2. I've had a few people tell me these aren't good EME
 > antennas. Using computer models they seem to be about the same as other
 > 30 foot boom length models. Granted the advertized gain figures are
 > inflated but is there a real reason why these don't compare with other
 > similar size yagi antennas (or make a poor EME choice)?

There seems to be a consensus that the 17B2 is a good antenna. A good
choice if your looking for something with a ~30 foot boom length. SM7SJR
is using a box of 17B2s.

 > 2. It seems some stations are starting to use smaller antennas
 > (10 elements, K5GW style?) for 2m EME arrays. I'm told they provide a
 > great pattern but my *limited* modeling of small yagis hasn't shown
 > this. What is the advantage of this approach?

VE7BQH replied:
The K5GW 10 element is a superior antenna for its boomlength. 4 of these
antennas will work on EME but are really too marginal for the long pull.
8 make a fine EME array. The G/T** of this antenna is very good. These
antennas can be purchased in kit form from Texas Towers (K5GW, Gerald)
Optimum stacking for this antenna is: 3.45M E Plane 3.16M H Plane. There
is No advantage to shorter booms unless you need shorter booms to fit your
physical needs. Assuming good design, GAIN is GAIN. The more the better.
The longer the antenna the more gain! The end result is what fits your
needs on the property you have.

** More on G/T later  - K0GU

 > 3. What antenna/stacking/spacing do you prefer for 2m EME?

VE7BQH has already calculated the distances for a large number of
different antennas.

The following is some great data by VE7BQH. One of the factors on the
chart below is G/T which BQH described as:

 G/T in simple words is forward gain divided by the sum of all of the rear
and side lobes temperatures of an antenna or array. This gives you a true
figure of merit, not just forward gain.

Well it was simple for him :-)

Enjoy,

73, Jay  K0GU                  

==========================================================================

VE7BQH G/T chart
144 MHz Yagi antenna comparative chart and G/T simulations of
a 4 bay array of Yagi antennas on 2 meters, 144.1 MHz
Issue 75 / April 2010

 TYPE OF        L     GAIN      E      H      Ga      Tlos    Ta       F/R      Z       VSWR      G/T
 ANTENNA       (WL)   (dBd)    (M)    (M)    (dBd)    (K)     (K)      (dB)   (ohms)  Bandwidth 
 
 G4CQM 6       1.00    9.46    2.60   2.17   15.44    7.90    249.70   18.9    56.7    1.83:1    -6.38
+G0kSC 6LFA    1.13    9.71    2.60   2.19   15.66    3.20    236.40   24.5    49.3    1.04:1    -5.93
+G0KSC 7LFA    1.39   10.62    2.84   2.49   16.53    1.80    248.90   20.4    48.0    1.19:1    -5.28
*G0KSC 7LFA    1.39   10.62    2.60   2.20   16.20    1.80    233.60   20.4    48.0    1.19:1    -5.34                     
 G4CQM 7       1.50   10.76    2.89   2.53   16.69    7.90    239.90   23.5    50.7    2.31:1    -4.96
+CT1FFU 7      1.54   10.82    2.87   2.50   16.70    2.80    237.70   20.3    28.0    1.02:1    -4.91
 DK7ZB 7       1.57   11.11    3.16   2.84   17.13    5.80    272.60   16.9    28.4    1.64:1    -5.07
 IK0BZY 6      1.63   11.11    3.10   2.77   17.04    4.80    266.50   17.8    19.5    2.27:1    -5.07
 G0KSC 8LFA    1.79   11.06    2.94   2.60   17.01    3.60    231.90   24.8    50.0    1.24:1    -4.49
*G0KSC 8LFA    1.79   11.06    3.15   2.40   16.95    3.60    222.20   24.8    50.0    1.24:1    -4.37
 W1JR 8 MOD    1.80   11.14    3.07   2.75   16.99    5.30    256.70   17.3    50.0    1.14:1    -4.95
 DJ9BV 1.8     1.80   11.34    3.16   2.80   17.28    5.50    261.20   17.6    77.5    1.34:1    -4.74
 K1FO 10       1.84   11.34    3.10   2.78   17.27    4.30    257.70   16.5    29.4    1.44:1    -4.69
 YU7EF 8       1.87   11.31    3.04   2.71   17.23    3.80    242.12   20.0    48.5    1.21:1    -4.46
 BQH8B         1.88   11.60    3.28   2.97   17.62    7.20    259.30   18.0    50.0    1.29:1    -4.37
+UR5EAZ 9      1.89   11.32    3.07   2.75   17.26    3.60    249.70   18.5    49.2    1.01:1    -4.56
 G4CQM 8       1.90   11.61    3.20   2.88   17.56    9.30    242.60   24.1    50.9    2.52:1    -4.14
+CT1FFU 8      1.94   11.28    2.96   2.62   17.10    2.90    232.30   23.6    27.1    1.05:1    -4.41
+G0KSC 8OWL    1.95   11.63    3.13   2.82   17.55    4.60    235.70   25.5    12.5    1.26:1    -4.02
 I0JXX 8       2.04   12.11    3.44   3.15   18.09    8.20    254.50   20.4    26.5    3.00:1    -3.82
*DG0OPK 9      2.07   11.45    2.95   2.70   17.30    5.70    230.80   24.6    28.4    1.11:1    -4.18
 DG0OPK 9      2.07   11.45    3.04   2.72   17.34    5.70    231.90   24.6    28.4    1.11:1    -4.16
 DK7ZB 8       2.09   12.01    3.40   3.10   18.02    4.80    253.60   21.6    28.0    1.26:1    -3.87
+G0KSC 9OWA    2.09   11.99    3.33   3.04   17.96    4.90    247.00   21.3    49.1    1.30:1    -3.82
+RA3AQ 9S      2.12   12.04    3.35   3.06   18.02    4.70    246.50   22.1    47.1    1.08:1    -3.75
*RA3AQ 9S      2.12   12.04    3.00   3.00   17.85    4.60    242.80   22.1    47.1    1.08:1    -3.85
 M2 9SSB       2.12   11.99    3.33   3.03   17.95    8.10    244.00   20.7    15.0    1.32:1    -3.71
 DJ9BV 2.1     2.13   11.89    3.33   3.04   17.87    5.80    255.20   20.2    44.9    1.30:1    -4.05
 G0KSC 9LFA    2.14   12.01    3.26   2.94   18.02    5.20    235.10   23.5    50.5    1.08:1    -3.68
*G0KSC 9LFA    2.14   11.97    3.10   3.00   17.86    5.20    235.70   23.5    50.5    1.08:1    -3.75   
*OZ5HF 9       2.16   11.52    2.70   2.50   16.65    2.90    275.10   18.2    38.0    1.15:1    -5.60
 OZ5HF 9       2.16   11.52    3.21   2.92   17.47    3.00    272.60   18.2    38.0    1.15:1    -4.74
 YU7EF 9       2.16   11.84    3.20   2.89   17.74    5.30    236.60   22.0    49.8    1.17:1    -3.84
 F9FT 11       2.17   11.78    3.26   2.97   17.75    5.30    251.00   22.7    21.5    1.25:1    -4.10  
*CC 13B2       2.17   11.79    2.90   2.79   17.47    5.80    249.10   19.6    21.1    1.37:1    -4.34
 CC 13B2       2.17   11.79    3.33   3.01   17.78    5.90    257.90   19.6    21.1    1.37:1    -4.18
 K1FO 11       2.18   11.97    3.30   3.00   17.90    4.30    248.00   17.9    44.0    1.29:1    -3.89
*CC 215WB      2.19   11.78    3.05   3.05   17.66    6.60    262.50   19.1    17.4    1.47:1    -4.38
 CC 215WB      2.19   11.78    3.36   3.07   17.78    6.60    266.60   19.1    17.4    1.47:1    -4.33
+G0KSC 9OWL    2.28   12.15    3.28   2.97   18.00    6.40    229.50   24.3    12.4    1.16:1    -3.46
*Flexa 224     2.34   11.52    3.50   3.30   17.66   30.10    259.20   17.7    60.4    1.09:1    -4.33
 Flexa 224     2.34   11.52    3.30   3.00   17.47   29.50    254.60   17.7    60.4    1.09:1    -4.44
+RA3AQ 9       2.35   12.38    3.40   3.13   18.31    5.60    234.30   22.1    49.2    1.10:1    -3.24
#RA3AQ 9       2.35   12.38    3.27   3.27   18.32    5.60    235.70   22.1    49.2    1.10:1    -3.25
+CT1FFU 9      2.38   12.23    3.26   2.97   18.08    3.60    226.80   22.7    28.1    1.15:1    -3.33
 ZL1RS 9       2.38   12.24    3.30   3.01   18.13    5.60    227.2    25.2    48.7    2.19:1    -3.28      
 Eagle 10      2.38   12.28    3.44   3.16   18.27    6.00    242.96   22.0    23.6    1.33:1    -3.43
 DK7ZB 9       2.39   12.41    3.56   3.30   18.45    6.20    250.50   20.4    27.5    1.23:1    -3.39
+YU7EF 10LT    2.49   11.84    3.13   2.82   17.69    5.30    224.30   29.4    45.7    1.13:1    -3.67
 K5GW 10       2.49   12.45    3.44   3.16   18.38    7.40    234.60   23.1    37.4    1.41:1    -3.17
#K5GW 10       2.49   12.45    3.30   3.30   18.38    7.30    235.90   23.1    37.4    1.41:1    -3.20
+G0KSC 10LFA+2 2.49   12.45    3.39   3.09   18.35    4.10    226.70   23.8    47.4    1.24:1    -3.06
 G4CQM 9       2.52   12.63    3.62   3.35   18.68    7.30    244.40   22.2    46.4    2.02:1    -3.05
 K1FO 12       2.53   12.49    3.46   3.18   18.42    4.30    240.70   21.6    31.1    1.23:1    -3.25
*YU7EF 10      2.59   12.44    3.38   3.09   18.33    6.90    227.50   23.8    50.3    1.06:1    -3.09
 YU7EF 10      2.59   12.44    3.39   3.10   18.34    6.90    227.80   23.8    50.3    1.06:1    -3.08
+G0KSC 10OWL   2.63   12.46    3.40   3.10   18.36    7.20    224.60   26.4    12.3    1.11:1    -3.00
 I0JXX 12      2.68   12.67    3.58   3.30   18.64    6.90    238.00   25.2    26.9    1.31:1    -2.97
 BQH 12J       2.80   12.80    3.67   3.40   18.83    4.30    246.20   20.3    50.0    1.01:1    -2.93
#BQH 12J       2.80   12.80    3.54   3.54   18.81    4.30    248.00   20.3    50.0    1.01:1    -2.99
+CT1FFU 10     2.82   12.74    3.44   3.15   18.59    4.10    220.20   25.2    28.1    1.19:1    -2.69
+CT1FFU 10C    2.82   13.04    3.62   3.31   18.93    4.20    222.90   27.2    27.2    1.23:1    -2.40
*M2 12         2.84   12.68    3.05   3.05   18.19    5.40    232.20   19.5    37.0    1.13:1    -3.32
 M2 12         2.84   12.68    3.48   3.20   18.54    5.40    232.50   19.5    37.0    1.13:1    -2.97
 BQH 10        2.86   13.05    3.69   3.43   19.00    7.00    232.50   23.9    22.6    1.47:1    -2.51             
#BQH 10        2.86   13.05    3.56   3.56   19.00    6.90    232.80   23.9    22.6    1.47:1    -2.52
 WB9UWA 12     2.87   12.73    3.48   3.20   18.61    7.00    223.00   25.2    23.9    1.47:1    -2.72
 DK7ZB 10      2.87   13.00    3.87   3.60   19.17    6.80    247.50   21.7    25.8    1.61:1    -2.62
+YU7EF 11B     2.87   12.92    3.58   3.30   18.85    4.70    225.60   25.6    50.2    1.35:1    -2.53
 K1FO 13       2.89   12.94    3.64   3.39   18.88    4.60    239.20   19.7    24.7    1.38:1    -2.76
 G0KSC 11LFA   2.95   13.11    3.66   3.37   19.02    5.50    223.60   25.4    48.4    1.03:1    -2.33
*G0KSC 11LFA   2.95   13.11    3.65   3.65   19.10    5.50    226.10   25.4    48.4    1.03:1    -2.29                   
*M2 20 XPOL    2.97   13.07    3.65   3.65   19.05    7.40    241.70   21.9    21.0    1.28:1    -2.63
#M2 20 XPOL    2.97   13.07    3.63   3.63   19.03    7.40    241.10   21.9    21.0    1.28:1    -2.64
 M2 20 XPOL    2.97   13.07    3.75   3.50   19.05    7.40    239.50   21.9    21.0    1.28:1    -2.59
+G0KSC 11OWL   3.00   13.16    3.69   3.44   19.09    7.70    224.60   23.0    11.9    1.23:1    -2.27
*BVO-3WL       3.01   13.43    3.90   3.70   19.38    8.60    253.10   20.5    52.7    3.08:1    -2.50
 BVO-3WL       3.01   13.43    4.03   3.78   19.42    8.60    256.10   20.5    52.7    3.08:1    -2.51
#BVO-3WL       3.01   13.41    3.90   3.90   19.41    8.60    256.60   20.5    52.7    3.08:1    -2.53
+YU7EF 11      3.04   13.07    3.56   3.30   18.87    4.70    222.60   22.2    49.0    1.62:1    -2.46
 F9FT 16       3.06   12.64    3.54   3.26   18.63    6.00    241.30   21.1    20.8    1.37:1    -3.05
 CD15LQDver2   3.09   12.90    3.58   3.33   18.85    4.40    231.60   26.1    19.1    1.25:1    -2.65
*CD15LQDver2   3.09   12.90    4.00   3.80   19.02    4.40    238.80   26.1    19.1    1.25:1    -2.61
 CD15LQDver1   3.10   12.83    3.60   3.35   18.76    4.10    247.80   20.7    22.0    1.23:1    -3.03
*CD15LQDver1   3.10   12.83    4.00   3.80   18.97    4.20    249.90   20.7    22.0    1.23:1    -2.86
 MBI ModFT17   3.12   13.29    3.85   3.60   19.27    8.20    239.50   24.3    50.1    1.41:1    -2.37
*F9FT 17       3.14   12.87    3.68   3.50   18.90    5.80    236.40   23.0    25.8    1.32:1    -2.69
 F9FT 17       3.14   12.87    3.59   3.31   18.81    5.70    234.30   23.0    25.8    1.32:1    -2.74
*CC3219        3.17   12.77    4.27   3.66   18.80    5.70    307.80   14.9    18.3    1.49:1    -3.93
 CC3219        3.17   12.77    4.07   3.82   18.79    5.70    308.60   14.9    18.3    1.49:1    -3.95
 CC3219 MOD    3.17   13.25    3.87   3.62   19.27    5.10    245.60   24.1    29.0    1.06:1    -2.48
 BQH 13        3.19   13.30    3.85   3.60   19.28    4.30    244.90   20.8    50.0    1.11:1    -2.46
#BQH 13        3.19   13.30    3.72   3.72   19.27    4.30    246.30   20.8    50.0    1.11:1    -2.49
 DJ9BV 3.2     3.22   13.30    3.85   3.58   19.29    6.50    239.50   21.1    71.8    1.36:1    -2.35
 G0KSC 12LFA   3.32   13.44    3.78   3.52   19.36    4.00    220.50   24.4    49.9    1.07:1    -1.92
 K1FO 14       3.26   13.36    3.80   3.56   19.29    4.70    237.80   18.1    29.6    1.42:1    -2.32
 G4CQM 11      3.36   13.55    3.92   3.66   19.50    8.30    232.00   30.1    46.2    1.94:1    -2.01
 DK7ZB 11      3.40   13.60    3.92   3.66   19.52    6.10    233.20   22.5    27.2    1.27:1    -2.01
 MBI 3.4       3.42   13.58    3.87   3.62   19.49    9.20    227.70   23.0    37.7    1.62:1    -1.93
 YU7EF 12      3.49   13.67    3.85   3.60   19.55    6.10    221.10   23.6    45.4    1.77:1    -1.75
*SM5BSZ 11     3.51   13.95    3.50   3.50   19.48    6,40    231.80   19.5    54.4    3.06:1    -2.02
+SM5BSZ 11     3.51   13.95    4.05   3.80   19.81    6.30    238.80   19.5    54.4    3.06:1    -1.82
*SM5BSZ 11A    3.53   14.01    4.00   4.00   19.92    6.10    245.80   16.7    52.3    3.03:1    -1.84
+SM5BSZ 11A    3.53   14.01    4.13   3.92   19.93    6.10    245.40   16.7    52.3    3.03:1    -1.82
 17LQD EKM#1   3.59   13.30    3.75   3.52   19.21    4.20    242.10   20.8    22.2    1.23:1    -2.48
 17LQD EKM#2   3.59   13.39    3.75   3.50   19.32    4.50    227.50   25.6    19.5    1.25:1    -2.10
 DJ9BV 3.6     3.61   13.67    4.00   3.78   19.57    5.40    249.70   21.3    53.5    1.30:1    -2.25
 K1FO 15       3.64   13.76    3.94   3.71   19.67    4.80    233.00   20.0    39.1    1.30:1    -1.85
+G0KSC 13LFA   3.78   13.85    3.92   3.66   19.73    4.20    217.10   28.4    49.9    1.08:1    -1.49
*G0KSC 13LFA   3.78   13.85    4.10   3.90   19.82    4.20    217.10   28.4    49.9    1.08:1    -1.49
 YU7EF 13M     3.86   13.85    3.92   3.66   19.73    7.00    218.80   25.7    49.9    1.05:1    -1.52
 DK7ZB 12      3.83   14.17    4.21   4.00   20.11    6.90    237.40   25.6    26.8    1.46:1    -1.49
+YU7EF 13      3.92   14.12    4.05   3.82   20.00    6.00    220.10   22.5    47.9    2.55:1    -1.28
 IK0BZY 12     3.98   14.18    4.16   3.92   20.08    8.10    232.50   20.8    23.6    1.52:1    -1.43
 BVO2-4WL      3.99   14.17    4.24   4.02   20.14    6.80    241.80   24.0    45.0    1.25:1    -1.54
#BVO2-4WL      3.99   14.17    4.13   4.13   20.11    6.80    241.20   24.0    45.0    1.25:1    -1.56
 DJ9BV 4.0     4.01   14.04    4.16   3.92   19.91    6.50    249.40   22.4    41.5    1.35:1    -1.91
 K1FO 16       4.01   14.13    4.16   3.87   20.05    4.70    229.90   23.9    35.0    1.15:1    -1.42
+SV 2SA13      4.01   14.45    4.38   4.16   20.42    7.00    239.00   20.0    52.2    1.41:1    -1.21
#SV 2SA13      4.01   14.45    4.27   4.27   20.42    7.00    238.80   20.0    52.2    1.41:1    -1.21
 HG VB-215DX   4.03   14.10    4.21   3.97   20.00    5.80    250.80   19.6    38.6    1.41:1    -1.84
 CC3219 MOD    4.04   14.13    4.27   4.07   20.09    5.10    248.20   24.0    32.1    1.02:1    -1.71
*CC4218XL      4.19   13.92    4.08   3.85   19.74   11.10    260.20   16.8    14.5    1.72:1    -2.26
 CC4218XL      4.19   13.92    4.31   4.07   19.82   11.10    263.60   16.8    14.5    1.72:1    -2.24
 CC4218 MOD    4.17   14.27    4.24   4.02   20.21    5.80    236.90   22.0    22.0    1.18:1    -1.39
 WB9UWA 15     4.18   13.65    3.75   3.50   19.44    8.30    208.90   34.0    26.0    1.51:1    -1.61
 YU7EF 14M     4.24   14.23    4.07   3.85   20.08    7.00    220.10   24.6    48.6    1.07:1    -1.20
+G0KSC 14LFA   4.24   14.29    4.16   3.94   20.21    3.20    219.00   28.1    50.5    1.06:1    -1.05              
*G0KSC 14LFA   4.24   14.29    4.00   4.00   20.18    3.20    219.10   28.1    50.5    1.06:1    -1.08          
 YU7EF 14      4.37   14.48    4.21   4.00   20.33    8.80    220.00   22.8    41.0    2.30:1    -0.94
 YU7EF 14LT    4.37   13.91    3.89   3.64   19.60   11.70    211.00   29.1    47.8    1.29:1    -1.49
 K1FO 17       4.40   14.44    4.24   4.02   20.34    4.90    229.50   22.9    27.7    1.25:1    -1.12
 DJ9BV 4.4     4.41   14.32    4.27   4.07   20.18    6.60    251.50   19.6    38.3    1.36:1    -1.68
 SHARK 20      4.47   14.34    4.33   4.10   20.19    3.90    258.50   22.4    42.8    1.05:1    -1.79
 I0JXX 16      4.47   14.36    4.16   3.94   20.24    8.40    217.60   27.6    30.4    1.05:1    -0.99
#I0JXX 16      4.47   14.36    4.05   4.05   20.24    8.40    217.50   27.6    30.4    1.05:1    -0.98
*CC17B2        4.49   14.52    3.66   3.51   19.93    6.10    223.40   23.4    29.3    1.22:1    -1.41
 CC17B2        4.49   14.52    4.27   4.05   20.42    6.20    226.80   23.4    29.3    1.22:1    -0.99
+RA3AQ-14      4.61   14.71    4.27   4.07   20.55    5.00    219.10   28.4    50.8    1.19:1    -0.71
 G4CQM 16      4.64   14.30    4.19   3.97   20.12    5.50    239.50   24.3    48.3    1.10:1    -1.51
 YU7EF 15M     4.68   14.59    4.21   4.00   20.40    7.00    221.70   25.7    48.6    1.03:1    -0.89
+G0KSC 15LFA   4.69   14.56    4.21   3.99   20.42    4.60    215.00   26.9    51.1    1.10:1    -0.76
*G0KSC 15LFA   4.69   14.56    4.45   4.60   20.57    4.60    215.60   26.9    51.1    1.10:1    -0.62   
 DK7ZB 14      4.73   14.92    4.59   4.39   20.87    6.80    233.00   26.2    26.9    1.50:1    -0.65
 K1FO 18       4.78   14.72    4.36   4.16   20.61    5.00    229.30   20.5    27.9    1.32:1    -0.84
*M2 28 XPOL    4.81   15.16    4.50   4.50   20.98   14.50    241.90   21.0    13.9    4.91:1    -0.71
#M2 28 XPOL    4.81   15.16    4.79   4.79   21.12   14.60    240.60   21.0    13.9    4.91:1    -0.54
 M2 28 XPOL    4.81   15.16    4.89   4.70   21.12   14.70    241.40   20.1    13.9    4.91:1    -0.56
 DJ9BV 4.8     4.82   14.63    4.40   4.19   20.48    6.60    242.80   21.0    49.7    1.29:1    -1.22
*M2 5WL        4.83   14.67    4.15   3.84   20.29    7.90    249.60   20.4    30.7    1.54:1    -1.53
 M2 5WL        4.83   14.67    4.56   4.36   20.55    8.10    250.40   20.4    30.7    1.54:1    -1.29
 YU7EF 15      4.84   14.89    4.46   4.24   20.78   10.29    218.10   25.6    41.8    3.18:1    -0.46
*SM5BSZ 14A    4.89   15.13    4.00   4.00   20.65    7.80    231.50   20.7    55.3    5.63:1    -0.85
+SM5BSZ 14A    4.89   15.13    4.59   4.39   20.98    7.60    237.72   20.7    55.3    5.63:1    -0.63
+RA3AQ 15      4.92   15.16    4.67   4.49   21.11    6.80    232.40   24.4    51.7    1.12:1    -0.40
#RA3AQ 15      4.92   15.16    4.59   4.59   21.11    6.80    231.90   24.4    51.7    1.12:1    -0.39
*SM5BSZ 14     4.95   15.27    5.20   5.20   21.36    5.70    239.70   18.8    49.3    4.37:1    -0.29
+SM5BSZ 14     4.95   15.27    4.73   4.52   21.14    5.70    241.47   18.8    49.3    4.37:1    -0.54
 K5GW 17       4.98   14.83    4.43   4.21   20.73    9.80    220.80   25.7    48.5    1.73:1    -0.56
 SM2CEW 19     4.99   14.85    4.49   4.27   20.78   11.60    224.20   22.3    20.4    1.81:1    -0.57
#SM2CEW 19     4.99   14.85    4.38   4.38   20.78   11.60    223.90   22.3    20.4    1.81:1    -0.56
*BVO-5WL       5.02   15.00    4.58   4.40   20.92    6.90    237.20   26.3    47.4    1.26:1    -0.68
#BVO-5WL       5.02   15.00    4.58   4.58   20.97    6.90    236.16   26.3    47.4    1.26:1    -0.61
 BVO-5WL       5.02   15.00    4.66   4.49   20.96    6.90    236.90   26.3    47.4    1.26:1    -0.64
 YU7EF 16M     5.12   14.90    4.36   4.16   20.70    7.00    221.90   25.1    49.9    1.03:1    -0.61
 K1FO 19       5.16   15.01    4.49   4.27   20.89    5.10    226.90   21.2    33.9    1.32:1    -0.52
#RU1AA 15      5.27   15.44    4.78   4.78   21.38    9.20    230.90   25.2    54.6    3.70:1    -0.10
 RU1AA 15      5.27   15.44    4.87   4.70   21.37    9.20    231.70   25.2    54.6    3.70:1    -0.13
*M2 18XXX      5.30   14.98    4.27   3.96   20.63    8.20    234.90   22.9    34.9    1.15:1    -0.93
 M2 18XXX      5.30   14.98    4.56   4.36   20.89    8.30    232.90   22.9    34.9    1.15:1    -0.63
 YU7EF 16      5.42   15.15    4.46   4.27   20.95    7.30    218.89   22.1    43.9    2.50:1    -0.30
+G0KSC 17LFA   5.59   15.12    4.43   4.21   20.94    5.00    208.70   30.0    49.4    1.12:1    -0.11
*G0KSC 17LFA   5.59   15.12    4.75   4.45   21.06    5.00    209.10   30.0    49.4    1.12:1    +0.01
*M2 19XXX      5.71   15.32    4.27   4.04   20.86    7.70    230.40   23.9    29.0    1.55:1    -0.61
 M2 19XXX      5.71   15.32    4.70   4.52   21.24    7.90    226.80   23.9    29.0    1.55:1    -0.17
#M2 32 XPOL    5.74   15.77    5.05   5.05   21.73   14.40    231.90   23.6    11.2    4.49:1    +0.23
 M2 32 XPOL    5.74   15.77    5.13   4.97   21.72   14.40    232.40   23.6    11.2    4.49:1    +0.21
 DK7ZB 17      5.82   15.61    5.01   4.85   21.59    8.60    227.80   24.8    26.8    1.19:1    +0.16
 YU7EF 17      5.88   15.70    4.85   4.63   21.53    9.60    223.80   24.0    41.2    2.92:1    +0.18
#YU7EF 17      5.88   15.70    4.74   4.74   21.53    9.60    223.57   24.0    41.2    2.92:1    +0.19
 BVO-6WL       6.00   15.65    4.77   4.93   21.55    7.00    227.30   24.9    44.9    1.14:1    +0.13
#BVO-6WL       6.00   15.65    4.85   4.85   21.59    7.10    226.70   24.9    44.9    1.14:1    +0.19
 AF9Y 22       6.14   15.73    5.01   4.85   21.66   13.10    221.40   24.9    19.1    2.65:1    +0.36
+RA3AQ 18      6.28   16.09    5.13   4.97   22.01    8.00    223.40   26.9    54.9    1.13:1    +0.67
*RA3AQ 18      6.28   16.09    5.30   5.30   22.12    8.10    222.30   26.9    54.9    1.13:1    +0.80
#RA3AQ 18      6.28   16.09    5.05   5.05   22.01    8.00    222.90   26.9    54.9    1.13:1    +0.68
 MBI 6.6       6.58   16.15    5.50   5.31   22.17   11.50    228.33   26.9    16.3    1.50:1    +0.73
#MBI 6.6       6.58   16.15    5.41   5.41   22.17   11.50    228.20   26.9    16.3    1.50:1    +0.74
 DK7ZB 19      6.59   16.15    5.41   5.22   22.15    8.20    230.20   24.0    27.7    1.97:1    +0.68
 BQH 25        7.30   16.38    5.27   5.09   22.28    8.80    217.10   25.5    27.9    1.16:1    +1.06
#BQH 25        7.30   16.38    5.18   5.18   22.28    8.90    216.80   25.5    27.9    1.16:1    +1.07
 K2GAL 21      7.65   16.90    5.71   5.55   22.81   13.30    223.90   26.3    17.2    9.01:1    +1.46
 M2 8WL(old)   7.72   16.51    5.31   5.13   22.34    9.10    221.90   21.3    16.7    2.21:1    +1.03
 M2 8WLHLD     8.05   17.00    6.05   5.88   22.97   13.60    234.30   25.4    18.2    4.48:1    +1.42

Legend:

1. L      = Length in Wavelengths

2. Gain   = Gain in dBd of a single antenna

3. E      = E plane (Horizontal) stacking in Meters. 

4. H      = H plane (Vertical) stacking in Meters.

5. Ga     = Gain in dBd of a 4 bay array

6. Tlos   = The internal resistance of the antenna in degrees Kelvin.

7. Ta     = The total temperature of the antenna or array in degrees Kelvin. This 
            includes all the side lobes, rear lobes and internal resistance of the 
            antenna or array.
8. F/R    = Front to Rear in dB over the rear 180 degrees of an antenna using either E or H plane. 

9. Z ohms = The natural impedence of a single antenna in free space.  

10. VSWR  = VSWR Bandwidth is based a single antenna over 144.000 - 145.000 MHz with a 
            reference of 1.00:1 at 144.100 MHz. This parameter gives an indicator of the
            antenna "Q" and what to expect with with stacking and wet weather.  
 
11. G/T   = Figure of merit used to determine the receive capability of the antenna
            or array = (Ga + 2.15) - (10*log Ta). The more positive figure the 
            better.

   Notes:
        
1. The programs used to calculate E/H Stacking,G,Ta,Tlos and G/T are
   EZNEC 5+ by Roy Lewallen, W7EL and Tant.exe by Sinisa, YT1NT/VE3EA.  
   This combination of software provides excellent accuracy. Segment Density is as 
   follows: Reflector and Directors = 25 segments. Split Dipole = 29.
   G0KSC loop = 39,39,7,7.     

2. Temperatures used: Tsky=200 degrees;Tearth=1000 degrees

3. Dipole Z is measured at 144.1 MHz

4. No stacking harness losses or H frame effects are included in the 4 bay gain figures.

5. All stacking dimensions EXCEPT those marked with a "*" and "#" are
   calculated from the DL6WU stacking formula.

6. Antennas marked with a "*" have stacking dimensions recommended by 
   the manufacturer or designer.

7. Antennas marked with a "#" have stacking dimensions for XPOL
   antennas by VE7BQH.

8. Antennas marked with a "+" have some or all elements over 6mm. All others
   are 4MM to 6MM.

9. Manufacturer/Designer Legend:

   AF9Y      = AF9Y            K1FO      = K1FO        
   BVO       = Eagle/DJ9BV     K2GAL     = K2GAL     
   BQH       = VE7BQH          K5GW      = Texas Towers/K5GW     
   CC        = Cushcraft       M2        = Mē 
   CC MOD    = VE7BQH          MBI       = F/G8MBI/F5VHX  
   CD        = CUE DEE         OZ5HF     = Vargarda
   CD MOD    = VE7BQH          RA3AQ     = RA3AQ
   DJ9BV     = DJ9BV           RU1AA     = RU1AA
   DJ9BV OPT = DJ9BV           SHARK     = SHARK (Italian)
   DK7ZB     = DK7ZB           SM2CEW    = SM2CEW/VE7BQH
   EKM MOD   = SM2EKM          SV        = Svenska Antennspecialisten AB 
   F9FT      = F9FT            W1JR      = VE7BQH (Mininec error)
   Flexa     = FlexaYagi       WB9UWA    = WB9UWA
   G0KSC LFA = G0KSC           YU7EF     = YU7EF
   G4CQM     = G4CQM           UR5CSZ    = UR5CSZ
   HG        = HYGAIN          
   I0JXX     = I0JXX                            
                               
                               


Using this Chart:

While Gain is important, other factors like ease of matching and wet weather performance should be 
considered in the your decision making. Antennas with 50 ohm feed systems and good VSWR bandwidth (Q) 
may be the best choice depending on your location. Low sidelobe and F/R antennas with good (G/T) may 
provide further signifcant benefit if you have local man made noise that is in directions where these 
kinds of antennas provide additional suppression.  
       

                                                                      LIONEL H. EDWARDS
                                                                      VE7BQH
                                                                      Issue 75 April 25, 2010

Issue 51: Add YU7EF Antennas
Issue 52: Update all DK7ZB antennas to latest published data. Add DK7ZB 8
Issue 53: Replace BQH8A with BQH8B a 50 ohm antenna
Issue 54: Add YU7EF 8
Issue 55: Add YU7EF 17 & YU7EF 11B
Issue 56: Add YU7EF 16
Issue 57: Add a revised YU7EF 10
Issue 58: Add DK7ZB 19
Issue 59: Add YU7EF 10LT
Issue 60: Add columns of Z and VSWR bandwidth to give indicators of Q and wet weather performance.
Issue 61: Add UA5EAZ 9. Add VSWR bandwidth for folded dipole to RA3AQ 9. Add RA3AQ 14
Issue 62: Revised Note 1 to explain limitations in YA 3.54 and the change to EZNEC 5+ and Tant.exe software
Issue 63: Add new low noise wide VSWR bandwidth YU7EF 13M,14M,15M,16M series antennas
Issue 64: Add YU7EF 14LT;Add G4CQM 8,9,11,16;Add G0KSC 9LFA
Issue 65: Add G0KSC 11LFA,G0KSC 14LFA;Add DK7ZB 7;Add K1FO 10,11,16
Issue 66: Conversion to EZNEC 5+ & Tant.exe completed. Add G0KSC 8LFA, G0KSC 12LFA,G0KSC 13LFA: RA3AQ 9S
Issue 67: Data corrected for RA3AQ 9S
Issue 68: Add G4CQM 8 updated to new version,Add ZL1RS 9, 
Issue 69: Add G0KSC 15LFA,G0KSC 17LFA. Segment Density changed to improve impedence accuracy. 
Issue 70: Add G0KSC 7LFA, Add Front to Rear column (F/R)
Issue 71: Add G0KSC 9,G4CQM 7,G4CQM 6,8 & 9 updated versions
Issue 72: Add G0KSC 10 LFA;Revised G4CQM 11,
Issue 73: Add G0KSC 9OWL,G0KSC 11,
Issue 74: Add G0KSC 6 LFA,G0KSC 8OWL,Revised G0KSC 9OWL,G0KSC10OWL, 
Issue 75: Add CT1FFU 7,CT1FFU 8,CT1FFU 9,CT1FFU 10,CT1FFU 10C
  
==========================================================================


1. BOOM CORRECTION FOR THROUGH THE BOOM INSULATED ELEMENTS ON 2 METERS
   & 70CM.

   PROVEN ACCURATE FOR BOOM DIAMETERS SMALLER THAN .055 WAVELENGTHS.
   MEASUREMENTS BY DL6WU.FORMULA BY G3SEK.

   FORMULA: C = 12.5975B - 114.5B^2
            C = CORRECTION FACTOR AS A FRACTION OF THE BOOM DIA.
            B = BOOM DIA IN WAVELENGTHS
            B^2 MEANS B SQUARED

   2 METERS
   BOOM DIAMETER           CORRECTION               ADD
   2 METERS.
   0.750" OR 19.050MM        10.56%          .0792" OR  2.01MM
   0.875" OR 22.225MM        12.10%          .1058" 0R  2.69MM
   1.000" OR 25.400MM        13.66%          .1366" OR  3.47MM
   1.125  OR 28.575MM        15.12%          .1701" OR  4.32MM
   1.250" OR 31.750MM        16.54%          .2070" OR  5.25MM
   1.500" OR 38.100MM        19.21%          .2881" OR  7.31MM
   1.750" OR 44.450MM        21.67%          .3792  02  9.63MM
   2.000" OR 50.800MM        23.91%          .4782" OR 12.15MM
             20.000MM        11.04%                     2.21MM
             38.000MM        19.17%                     7.28MM

   70 CENTIMETERS.

   DJ9BV USES THE FOLLOWING CORRECTION ON 70CM:
   0.787" OR 20.000MM        25.00%          .1968" OR  5.00MM
   1.000" OR 25.400MM        20.00%          .2362" OR  6.00MM
   1.125" OR 28.575MM        24.50%          .2756" OR  7.00MM
   1.250" OR 31.750MM        25.20%          .3149" OR  8.00MM
   1.375" OR 34.925MM        25.77%          .3543" OR  9.00MM

   K1FO USES THE FOLLOWING CORRECTION ON 70CM:
   0.875" OR 22.225MM                               OR  6.44MM
   1.000" OR 25.400MM                               OR  8.12MM
   1.125" OR 28.575MM                               OR  9.57MM
   1.250" OR 31.750MM                               OR 11.43MM
   1.375" OR 34.925MM                               OR 13.27MM

   VE7BQH USES THE FOLLOWING CORRECTION ON 70CM:
   0.630" OR 16.000MM                               OR  3.67MM
   0.875" OR 22.225MM                               OR  5.00MM
   1.000" OR 25.400MM                               OR  7.00MM
   1.125" OR 28.575MM                               OR  9.00MM
   1.250" OR 31.750MM                               OR 10.69MM
   1.375" OR 34.925MM                               OR 11.64MM

   THERE IS NO DIFFERENCE IN CORRECTION FACTOR FOR ROUND OR SQUARE BOOMS.

2. ELEMENT DIAMETER CORRECTION ON 2 METERS
   THE FOLLOWING ARE SOME AVERAGE ELEMENT DIAMETER CORRECTIONS FOR 2M TO
   SCALE AN ANTENNA FOR A DIFFERENT DIAMETER ELEMENT.IT IS NOT SO SIMPLE
   AS JUST ADDING A SIMPLE LINEAR CORRECTION AS THE OVERALL TAPER CHANGES
   DEPENDING ON THE DIAMETER OF ELEMENT.AS A CONSEQUENCE THE CORRECTION
   VARIES FROM REFLECTOR TO LAST DIRECTOR.EG:6.25MM TO 5MM DIAMETER
   CORRECTION ON A 10 EL DJ9BV ANTENNA IS 2 MM AT THE REFLECTOR AND 6.91MM
   AT DIRECTOR 8.THE ABOVE WAS CALCULATED USING THE YOC 5.0 SCALING FEATURE

   DIA.  6.35MM   5.00MM   4.76MM   4.00MM  2.00MM
   ADD   0.00MM   4.50MM   5.00MM   8.00MM  12.0MM


3. CORRECTION FACTOR FOR CUSHCRAFT AND CUDEE STYLE MOUNTED ELEMENTS

   CUSHCRAFT CORRECTION FACTOR ON 2 METERS = .3125" OR 7.94MM
   CUDEE CORRECTION FACTOR ON 2 METERS     = .2500" OR 6.35MM

4. DL6WU STACKING FORMULA

   Dopt =   WAVELENGTH / 2 SIN (beamwidth/2)

   GOOD RESULTS CAN BE OBTAINED DOWN TO 90 PERCENT OF THE ABOVE FORMULA IF
   A SMALLER STACKING FRAME IS DESIRED.CLOSER STACKING THAN 90 PERCENT OF
   DL6WU'S FORMULA WILL RESULT IN A DEGRADATION OF G/T.

73,
Lionel,VE7BQH