Amateur Radio Station FG4NO (Via F4AVX)
19628 QSO in the log FG4NO
DXCC entities : 302 worked / 300 confirmed

   

 [ Home ]
 [ Logbook ]
 [ QSL information ]
 [ QSL cards ]
 [ DXCC ]
 [ L Inverted 40/80M ]

40893 visitors
since 01/01/2011

Last update :
log FG4NO - 21/08/17




 Après avoir testé de multiples a

L INVERTED 40/80M with optional 160M (Work 6 to 160M) par FG4NO

(Sorry for my translation :) )

 

Update: 15 February 2015

A small update is necessary because I forget some small details.

Regarding the balun UNUN there is a less expensive way.

You just need that little fixing and connecting air choke balun
(
See picture W4NFR)

Some OMs say that the horizontal strap should point to the north.

The cost of this antenna is inexpensive, it takes 125 to 150 euros
(10M HD Mast, 329 feet electric son and different small items)

 


 

***************************************************************************************************************

 

The 14 February 2015

After having tested multiple antennas with more or less good results, I have opted for the L inverted and gives you the explanation. It is scheduled for 40 / 80M (160M optional) but works on other bands.

Above all we must take into account my geographic situation that does not give me the right conditions to make some types of antennas. Take into consideration the earth, vegetation, coconut palms, trees, the earth that contains a lot of volcanic rocks, pebbles and not talking about this part of the land is sloping and necessarily in a bowl. There is nothing to help a good antenna and then flush the bowl also to make myself heard over 80M with my G5RV so I have opted for the L inverted. I have to say my brings enormously. She is still in the testing phase and I see something to do, I make changes.

So my construction of the L inverted and of course these values can be changed but given my limited space I took the length of 21.38m which gives an full wave 20M, half wave 40M and quarter wave 80M.

L Inverse FG4NO


I haven that place, to put my antenna and that not necessarily help with the fence, trees etc. I have the problem turns in all directions to find a solution but I see that it currently.


Materials used:


- Fiber Glass Mast 10M HD (Wimo)
- Balun UNUN 4/1 (Dx Engineering)
- Air choke balun (pvc pipe diameter 100 and 25 feet of coax -7.62m- 6mm)
- 30M coax (100 feet)
- 100m (329 feet) H07VK (1.5mm 2)


*******************************

Long wire of 21.38M (10M vertical and rest horizontal)
Radials: 1 80M (21.29m), 1 40m (10.67m), 1 30M (7.41m). Subsequently I have added two radials 1 and 1 21.34m 7.13m


*******************************

Remember that I do with of the earth, I repeat myself but take into account.

 

 

 

 

Here is what I get with 21.38M (FT450D and MFJ 969)

* ROS UP: Value without the tuner. The ros is a superior 3
 
   

L INVERTED 40/80M with optional 160M (Work 6 to 160M)

 

QRG

* ROS

TRANSMITTER

ANTENNA

INDUCTANCE

160M

1825

UP

2

3

016

80M

3510

UP

4

7

065

80M

3610

UP

4

6

068

80M

3710

UP

5

5

072

80M

3790

UP

5

4

075

40M

7005

UP

4

5

108

40M

7105

UP

3

7

107

30M

10125

1.5

X

X

X

20M

14005

2.2

5

5

118

20M

14180

2.0

4

5

119

20M

14280

2.0

3

5

119

17M

18100

1.3

X

X

X

15M

21005

2.8

5

3

121

15M

21105

2.5

5

3

121

15M

21205

2.1

5

4

122

15M

21305

2.0

4

5

121

12M

24930

1.1

X

X

X

10M

28070

2.9

4

2

121

10M

28450

2.5

5

5

122

 

Look at my logbook (http://fg4no.net/) the Qso 40M and 80M realized with this antenna and only with 100 watts from the 09.02.2015. I think it is a good start.

If you need to test this antenna, make changes, suggestions let me know.

See you soon on 40M and 80M.

73 de FG4NO, Nicolas

Contact me by e-mail
HamLogWeb beta 0.042 - F5AGL Creative Commons licence - This site is optimized for viewing at 1280*800 resolution
Creative Commons License