1. Shunt Fed Tower
Or If You Have a 50- to 60-Foot Tower with Something on Top, Here’s One Way You Can Get on 160M

2. My Situation City Lot Tribander for 10, 15, and 20M
Full-wave Delta Loop for 40M
What to do for 160M?

3. Use Existing Tower

4. Why a Vertical? Low take-off angle for DX Not a “space-saving” antenna
Needs radials – the more the better
Real World - 16 radials MINIMUM
Ten 10-foot radials better than one 100-foot

5. Construction Two wires 18 inches apart – fat conductor
Inside wire 3 feet from tower
Gamma section as long as possible
Weather-proof plastic box at base

8. EZNEC+ Version 5.0 f=1.825 MHz Z=27.59 + j556
Model
EZNEC+ Version 5.0
f=1.825 MHz Z= j556

9. --------------- SOURCE DATA --------------- Frequency = 1.825 MHz
EZNEC+ ver. 5.0
160M Shunt Fed 60Ft Tower
SOURCE DATA
Frequency = MHz
Source Voltage = V at deg.
Current = 1 A at 0.0 deg.
Impedance = J 556 ohms
Power = watts
SWR (50 ohm system) > 100

10. 160M Shunt Fed 60-Foot Tower

11. Autek Research RX VECTOR ANALYST Model VA1 f=1.825 MHz Z=440 + j300
Measured
Autek Research RX VECTOR ANALYST Model VA1
f=1.825 MHz Z=440 + j300

13. http://www.circuitsage.com/matching/matcher2.html L = 15 uH C = 558 pF
Matching Network
L = 15 uH C = 558 pF

14. Source --------- L = 15 uH ----------- Load | C = 558 pF | Gnd
Matching Network
Source L = 15 uH Load |
C = 558 pF | Gnd

15. Works okay for transmit Not so great for receive
On The Air
Works okay for transmit
Not so great for receive

17. Possible Problem Rotor in tower – controller may not be happy
Solution disconnect rotator control cable before transmitting