144 MHz yagis
- this page was revised to include September 2007 G/T data -
Date: Tue, 16 Apr 1996 09:05:42
From: Jay Kesterson, jayk@BITS.FC.HP.COM
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 jayk@fc.hp.com
==========================================================================
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 56 / September 2007
TYPE OF L GAIN E H Ga Tlos Ta G/T
ANTENNA (WL) (dBd) (M) (M) (dBd) (K) (K) .
W1JR 8 MOD 1.80 11.17 3.09 2.76 17.15 3.04 266.57 -4.96
DJ9BV 1.8 1.81 11.38 3.16 2.80 17.31 3.16 267.12 -4.81
YU7EF 8 1.87 11.28 3.02 2.69 17.22 4.47 253.52 -4.68
BQH8B 1.88 11.66 3.29 2.98 17.67 4.96 263.60 -4.39
I0JXX 8 2.04 12.16 3.46 3.17 18.18 11.33 267.91 -3.95
DK7ZB 8 2.09 12.15 3.41 3.12 18.08 4.34 260.41 -3.93
M2 9 2.12 12.08 3.34 3.04 18.08 8.77 254.38 -3.83
DJ9BV 2.1 2.14 11.92 3.33 3.04 17.92 4.66 260.72 -4.10
*OZ5HF 9 2.16 11.75 2.70 2.50 17.21 2.95 264.46 -4.87
OZ5HF 9 2.16 11.75 3.25 2.96 17.71 2.99 262.13 -4.33
YU7EF 9 2.16 11.86 3.18 2.87 17.79 3.23 243.83 -3.94
F9FT 11 2.17 11.71 3.27 2.97 17.70 5.21 262.64 -4.35
*CC 13B2 2.17 11.83 2.90 2.79 17.67 4.40 256.63 -4.28
CC 13B2 2.17 11.83 3.33 3.04 17.83 4.46 263.15 -4.23
*CC 215WB 2.19 11.86 3.05 3.05 17.80 4.34 286.14 -4.62
CC 215WB 2.19 11.86 3.48 3.19 17.87 4.40 287.83 -4.58
RA3AQ-9 2.35 12.34 3.40 3.11 18.30 4.45 238.76 -3.33
#RA3AQ-9 2.35 12.34 3.26 3.26 18.37 4.44 240.91 -3.30
Eagle 10 2.38 12.28 3.44 3.15 18.29 6.07 249.46 -3.54
DK7ZB 9 2.39 12.49 3.62 3.35 18.53 4.93 262.30 -3.51
*Flexa 224 2.49 11.90 3.50 3.30 18.01 8.29 264.66 -4.07
Flexa 224 2.48 11.90 3.30 3.31 17.87 8.32 257.77 -4.10
K5GW 10 2.49 12.57 3.45 3.16 18.53 5.72 241.20 -3.15
#K5GW 10 2.49 12.57 3.30 3.30 18.58 5.76 242.35 -3.12
K1FO 12 2.53 12.49 3.46 3.18 18.44 3.51 245.43 -3.31
YU7EF 10 2.54 12.53 3.43 3.14 18.49 3.14 237.12 -3.11
I0JXX 12 2.68 12.69 3.59 3.32 18.68 4.45 247.49 -3.11
BQH 12J 2.80 12.82 3.66 3.40 18.85 3.09 252.88 -3.03
#BQH 12J 2.80 12.82 3.53 3.53 18.88 3.06 252.93 -3.06
*M2 12 2.84 12.79 3.05 3.05 18.59 5.19 237.40 -3.02
M2 12 2.84 12.79 3.48 3.21 18.71 5.15 237.98 -2.91
BQH 10 2.86 13.07 3.70 3.44 19.05 6.59 240.48 -2.62
#BQH 10 2.86 13.07 3.57 3.57 19.11 6.56 242.58 -2.59
DK7ZB 10 2.87 13.19 3.89 3.65 19.20 5.94 259.91 -2.80
YU7EF 11B 2.87 12.90 3.55 3.28 18.85 4.18 239.00 -2.62
WB9UWA 12 2.90 12.82 3.45 3.17 18.73 6.93 227.71 -2.70
BQH 13 2.92 13.09 3.69 3.44 19.07 3.92 241.77 -2.62
#BQH 13 2.92 13.09 3.57 3.57 19.11 3.95 243.09 -2.60
*M2 20 XPOL 2.97 13.19 3.65 3.65 19.20 6.74 252.79 -2.68
#M2 20 XPOL 2.97 13.19 3.65 3.65 19.20 6.74 252.79 -2.68
M2 20 XPOL 2.97 13.19 3.77 3.52 19.16 6.77 251.00 -2.69
*BVO-3WL 3.00 13.50 3.90 3.70 19.48 5.35 264.59 -2.60
BVO-3WL 3.00 13.50 4.01 3.77 19.49 5.38 266.39 -2.62
#BVO-3WL 3.00 13.50 3.89 3.89 19.52 5.45 265.97 -2.58
YU7EF 11 3.04 13.07 3.56 3.30 18.99 3.32 226.79 -2.42
*CD15LQD 3.11 12.87 4.00 3.80 18.96 4.57 261.85 -3.08
CD15LQD 3.11 12.87 3.68 3.42 18.86 4.49 259.53 -3.14
CD15LQD MOD 3.11 13.24 3.83 3.58 19.24 3.73 253.86 -2.66
MBI FT17 3.12 13.34 3.84 3.59 19.31 6.02 246.36 -2.46
*CC3219 3.14 12.66 4.27 3.66 18.64 4.62 349.69 -4.65
CC3219 3.14 12.66 4.05 3.80 18.65 4.65 354.61 -4.70
CC3219 MOD 3.14 13.32 3.91 3.67 19.32 3.74 258.52 -2.66
*F9FT 17 3.15 12.87 3.68 3.50 18.92 5.74 243.96 -2.81
F9FT 17 3.15 12.87 3.57 3.30 18.84 5.74 240.69 -2.83
DJ9BV 3.2 3.22 13.36 3.85 3.58 19.34 3.99 246.42 -2.42
K1FO 14 3.25 13.36 3.78 3.54 19.30 4.26 243.48 -2.42
MBI 3.4 3.41 13.69 3.88 3.63 19.63 7.68 235.12 -1.94
YU7EF 12 3.49 13.67 3.83 3.58 19.60 4.40 224.97 -1.78
*SM5BSZ 11 3.51 13.86 3.50 3.50 19.71 3.16 232.02 -1.80
SM5BSZ 11 3.51 13.86 3.96 3.72 19.79 3.13 238.58 -1.84
*SM5BSZ 11A 3.52 13.97 4.00 4.00 19.96 3.13 244.17 -1.77
SM5BSZ 11A 3.52 13.97 4.05 3.81 19.91 3.07 244.00 -1.82
17LQD EKM 3.59 13.37 3.83 3.59 19.35 4.57 252.49 -2.53
17LQDE BQH 3.59 13.79 4.04 3.81 19.77 3.95 248.40 -2.04
DJ9BV 3.6 3.61 13.73 4.00 3.77 19.64 4.25 258.21 -2.33
K1FO 15 3.65 13.78 3.94 3.70 19.70 3.33 238.55 -1.93
DK7ZB 12 3.83 14.25 4.30 4.08 20.26 5.69 250.62 -1.64
YU7EF 13 3.92 14.09 4.01 3.77 20.03 5.13 222.70 -1.30
DJ9BV OPT 3.99 14.22 4.29 4.08 20.18 4.99 248.48 -1.63
#DJ9BV OPT 3.99 14.22 4.19 4.19 20.21 5.03 247.16 -1.57
#SV 2SA13 4.01 14.46 4.20 4.20 20.44 4.67 246.84 -1.34
SV 2SA13 4.01 14.46 4.37 4.16 20.43 4.67 247.35 -1.36
DJ9BV 4.0 4.02 14.07 4.15 3.92 19.98 5.67 255.50 -1.95
HG215DX 4.02 14.20 4.25 4.03 20.14 6.44 258.47 -1.84
CC3219 MOD 4.05 14.20 4.34 4.13 20.17 4.28 256.17 -1.77
*CC4218XL 4.15 14.14 4.08 3.85 20.03 7.25 265.93 -2.07
CC4218XL 4.15 14.14 4.45 4.23 20.11 7.17 266.22 -2.00
WB9UWA 15 4.18 13.62 3.69 3.43 19.48 8.00 214.69 -1.69
CC4218 MOD 4.18 14.29 4.24 4.02 20.24 5.25 244.97 -1.51
YU7EF 14 4.37 14.58 4.23 4.00 20.51 4.63 223.20 -0.83
K1FO 17 4.41 14.44 4.22 4.00 20.35 4.34 234.51 -1.21
DJ9BV 4.4 4.42 14.36 4.28 4.06 20.25 6.19 256.51 -1.70
SHARK 20 4.46 14.39 4.32 4.10 20.26 2.90 264.04 -1.81
I0JXX 16 4.47 14.39 4.17 3.94 20.32 6.09 223.60 -1.03
#I0JXX 16 4.47 14.39 4.06 4.06 20.35 6.11 223.23 -0.99
*CC17B2 4.51 14.53 3.66 3.51 20.22 4.83 233.29 -1.31
CC17B2 4.51 14.53 4.28 4.06 20.47 4.99 234.82 -1.08
DK7ZB 14 4.71 15.04 4.73 4.54 21.02 6.90 245.10 -0.73
K1FO 18 4.77 14.72 4.35 4.14 20.63 4.54 234.66 -0.93
*M2 28 XPOL 4.80 15.22 4.50 4.50 21.14 17.04 258.67 -0.84
#M2 28 XPOL 4.80 15.22 4.76 4.76 21.22 17.15 257.77 -0.76
M2 28 XPOL 4.80 15.22 4.86 4.66 21.19 17.11 257.51 -0.77
HG217DX 4.82 14.81 4.63 4.43 20.78 8.14 256.05 -1.16
DJ9BV 4.8 4.83 14.65 4.40 4.18 20.57 5.85 255.84 -1.37
*M2 5WL 4.83 14.80 4.15 3.84 20.56 8.49 254.92 -1.36
M2 5WL 4.83 14.80 4.56 4.35 20.74 8.70 251.18 -1.11
YU7EF 15 4.84 14.98 4.44 4.23 20.92 4.89 221.29 -0.38
*SM5BSZ 14A 4.89 15.14 4.00 4.00 20.93 4.33 232.02 -0.58
SM5BSZ 14A 4.89 15.14 4.54 4.33 21.03 4.43 238.02 -0.59
RA3AQ-15 4.92 15.14 4.67 4.48 21.10 4.42 239.26 -0.54
#RA3AQ-15 4.92 15.14 4.56 4.56 21.12 4.43 239.19 -0.52
*SM5BSZ 14 4.95 15.29 5.20 5.20 21.37 3.13 246.72 -0.41
SM5BSZ 14 4.95 15.29 4.72 4.51 21.19 3.02 233.77 -0.68
SM2CEW 19 4.98 14.91 4.47 4.26 20.84 9.38 233.77 -0.70
#SM2CEW 19 4.98 14.91 4.37 4.37 20.87 9.00 232.88 -0.66
*BVO-5WL 5.02 15.05 4.58 4.40 20.99 5.21 243.42 -0.73
#BVO-5WL 5.02 15.05 4.59 4.59 21.04 5.24 242.36 -0.66
BVO-5WL 5.02 15.05 4.69 4.49 21.01 5.23 242.70 -0.70
K5GW 17 5.06 14.99 4.64 4.44 20.96 6.16 244.55 -0.78
K1FO 19 5.18 15.01 4.47 4.27 20.92 4.04 232.19 -0.59
#RU1AA 15 5.27 15.55 4.85 4.85 21.55 6.02 235.76 -0.03
RU1AA 15 5.27 15.55 4.85 4.65 21.50 5.99 236.28 -0.09
*M2 18XXX 5.32 15.07 4.27 3.96 20.85 7.90 243.30 -0.87
M2 18XXX 5.32 15.07 4.55 4.35 21.01 7.95 240.56 -0.66
YU7EF 16 5.42 15.22 4.49 4.28 21.10 5.41 223.39 -0.25
M2 32 XPOL 5.62 15.70 5.23 5.04 21.69 15.02 250.74 -0.16
#M2 32 XPOL 5.62 15.70 5.13 5.13 21.71 15.04 251.20 -0.15
*M2 19XXX 5.73 15.41 4.27 4.04 21.15 8.75 238.80 -0.49
M2 19XXX 5.73 15.41 4.70 4.51 21.36 8.75 235.52 -0.22
#M2 32 XPOL 5.73 15.88 5.07 5.07 21.87 16.03 248.46 +0.06
M2 32 XPOL 5.73 15.88 5.16 4.98 21.84 16.03 248.11 +0.04
DK7ZB 17 5.81 15.69 5.16 4.98 21.68 6.16 234.46 +0.12
YU7EF 17 5.87 15.78 4.84 4.64 21.68 5.29 229.75 +0.21
#YU7EF 17 5.87 15.78 4.74 4.74 21.71 5.31 229.47 +0.25
BVO-6WL 6.00 15.69 4.75 4.93 21.63 5.12 231.63 +0.13
#BVO-6WL 6.00 15.69 4.84 4.84 21.66 5.13 231.84 +0.15
AF9Y 22 6.15 15.75 5.04 4.86 21.72 10.04 230.73 +0.23
RA3AQ-18 6.28 16.11 5.13 4.96 22.05 4.97 227.80 +0.62
*RA3AQ-18 6.28 16.11 5.30 5.30 22.13 4.99 227.28 +0.71
#RA3AQ-18 6.28 16.11 5.05 5.05 22.08 4.98 227.31 +0.64
MBI 6.6 6.6 16.14 5.46 5.29 22.14 13.09 238.73 +0.51
#MBI 6.6 6.6 16.14 5.38 5.38 22.17 13.07 239.28 +0.53
BQH 25 7.29 16.31 5.22 5.04 22.25 9.83 224.18 +0.89
#BQH 25 7.29 16.31 5.13 5.13 22.28 9.86 224.61 +0.91
K2GAL 21 7.65 16.80 5.75 5.59 22.75 19.58 245.81 +0.99
M2 8WL(old) 7.71 16.55 5.28 5.10 22.40 9.52 231.46 +0.90
M2 8WL(new) 8.05 17.05 5.82 5.67 23.01 11.53 237.20 +1.40
Legend:
L = Length in Wavelengths
Gain = Gain in dBd of a single antenna
E = E plane (Horizontal) stacking in Meters.
H = H plane (Vertical) stacking in Meters.
Ga = Gain in dBd of a 4 bay array
Tlos = The internal resistance of the antenna in degrees Kelvin.
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.
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 Program used to calculate E/H Stacking,G,Ga and G/T is YAGI
ANALYSIS 3.54 by Goran Stenberg,SM2IEV.
2. Temperatures used: Tsky=200 degrees;Tearth=1000 degrees
3. All dipoles have been adjusted to give a J of under +/- .5
4. No stacking harness losses or H frame effects are included in the
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 10MM elements. All others
are 4MM to 6MM.
9. Manufacturer/Designer Legend:
AF9Y = AF9Y I0JXX = I0JXX
BVO = Eagle/DJ9BV K1FO = K1FO
BQH = VE7BQH K2GAL = K2GAL
CC = Cushcraft K5GW = Texas Towers/K5GW
CC MOD = VE7BQH M2 = M^2
CD = CUE DEE MBI = F/G8MBI
CD MOD = VE7BQH OZ5HF = Vargarda
DJ9BV = DJ9BV RA3AQ = RA3AQ
DJ9BV OPT = DJ9BV RU1AA = RU1AA
DK7ZB = DK7ZB SHARK = SHARK (Italian)
EKM MOD = SM2EKM SM2CEW = SM2CEW/VE7BQH
F9FT = F9FT SV = Svenska Antennspecialisten AB
HG = HYGAIN W1JR = VE7BQH (Mininec error)
Flexa = FlexaYagi WB9UWA = WB9UWA
YU7EF = YU7EF
LIONEL H. EDWARDS
VE7BQH
Issue 56 Sept 7, 2007
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
==========================================================================
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