Sunday, July 10, 2011

Contest Station SJ2W


This page contains information about our current setup. You can click on the different antenna system and see details and pictures of the antennas.


#1 60m high OH8QD tower which is rotational

#2 16m high rotational tower which is un-guyed, holding 6/6 for 10m.

#3 18m high tower, with G-1000SDX rotator


160m: Fullsize 1/4 vertical

80m: 4-SQ array

40m: 3el mono @60m + 4-SQ + Vertical

20m: 6/6/6el mono @55/39/23m + 4el @EU at 16m

15m: 6/6el mono @28/17m + 5el mono @19m

10m: 6/6el mono

RX Antennas

Beverage, 350m? (1150 feet) towards West Coast US (330 degrees)

Beverage, 550m (1800 feet) towards East Coast US (300 degrees)

Beverage, 280m (1050 feet) towards South America (260 degrees)

Beverage, 220m (720 feet) towards EU/Africa (180 degrees)

Beverage, 320m (1050 feet) towards South East (130 degrees)

Beverage, 450m (1480 feet) towards Australia (80 degrees)

Beverage, 750m (2460 feet) towards Japan (45 degrees)

10m antennas

The antenna system for 10m currently consist of a 6/6el monoband stack. This antenna system is thought out to be the 2nd antenna system on 10m when we in the future hope to add a big stack in another rotatable tower. This antenna system is located on a small rotatable tower which is telescopic and has got an Emotator 1103 turning it. The antennas are stacked at 15 over 9.5m and below you can see the stack responses to the important directions.

The antennas are CUE DEE but with rebuilt feed point system from gamma to hairpin.

This antenna is fed by a 7/8″ cable and the jumper cable up to the tower consist of about 8m 1/2″ superflex coax.

Future plans for this band is to hopefully in 2011 add another 6el yagi which will be at around 44m up in the 60m tower. Also plans are to add a 7/7/7/7el OWA stack as main antenna system, hopefully in the summer of 2012.

15m antennas

On 15m there are currently two different antenna systems. One is a 6/6el monoband stack located 28/17m up in the 60m tower and is currently the main antenna system. There is also a 5el monoband yagi sitting 19m up with an own rotator, and this is our so called independent multiplier antenna. Both antennas are modified CUE DEE antennas, which now has got hairpin matches instead of gamma.

The cable for the 6/6el stack is first a 7/8″ cable running out to the tower base. In the tower there is about 23m of RG-17 and after the stack box there is a RG-213 running out to each antenna. The 5el monobander has got a 7/8″ cable with a RG-217 jumper cable attached to the antenna.

For the future there are plans to put up a 7/7/7 or 7/7/7/7el OWA stack as a main stack in another tower.


20m antennas

The main antenna system on 20m consist of a 6/6/6el monoband stack, at 55/39/23m height. This antenna system has got a phase box making it possible to change the vertical lobe angle in four different steps. Either 7, 13, 17 or 25 degrees. The three antennas are always fed together, but there is a possibility to put in a 180 degree coax on two of the antennas, making it possible to switch it in four combinations. The phasing system in theory, makes it so that we have a maximum of 3dB drop between 6 and 28 degrees compared to max gain. These antennas are homebrew after OH8QD design (18.5m booms!), but with rebuilt feed point system from gamma to hairpin.

There is also a 4el monoband yagi with CUE DEE design but also with rebuilt feed point system from gamma to hairpin. This antenna sits 16m up in a 18m high tower, and is fixed Europe.

For the 6/6/6el stack there is a 7/8″ cable running from the switch room up to the phase box which is about 37m up in the 60m tower. From the phase box there are 3 pcs of RG-213 running out to each antenna. All connectors here are 7/16″ DIN. For the 4el monoband yagi there is a 7/8″ coax from the switch room up to the antenna, and a RG-217 jumper cable attached to the hairpin match.

Phase box details
Phase box progress

The future plans for this band is to add a secondary antenna system which will be a 5/5el stack sitting in a 40m rotatable tower. This will hopefully be done in 2011.

6/6/6el stack

40m antennas

On 40m the current main antenna is a 3el monobander (SJ2W design) which is sitting at 60m height. This antenna will become a 3/3el stack hopefully during the summer of 2011. There is also a 4-SQ which is used mainly as an RX antenna and is the freely “rotatable” multiplier antenna on this band, totally independent of the direction of any other antennas.

The 40m yagi is fed with a 7/8″ coax running from the switch room to the stack box up in the tower. After the stack box there is a RG-213 up to the antenna. The 40m 4-SQ is located about 170m from the house and fed with RG-17 coaxial cable.

Future plans for this band is to add the 2nd 3el yagi to make the big antenna system a 3/3el stack. There are also plans of a secondary direction system which will be 2/2el. We also need to straighten out the reflector which is currently twisted a bit on the boom.

80m antennas

The current main antenna on 80m and also the first real antenna put up at the QTH is the 4-SQ for 80m. It has got a COMTEK phase box and 1/4wl seperation of the verticals. Each vertical has got atleast 60 radials each which are > 1/4 wl, some are well over 1/2 wl. The antenna is sitting on posts to keep them above the snow in the winter and can be lowered fairly easy with a ladder. The verts are 60mm in the bottom and 12mm tips. Each vertical is about 20m tall and guyed at three levels with parafil. For guy anchors we use some iron bars which are 110cm long and put down into the ground, they are 10mm thick.

The coaxial cable running out to this antenna is a 60m long RG-17 which has got a metal protective coating.

The future plans for the 80m antenna system is to build a 2el yagi, probably a project for summer of 2013.


80m 4-SQ in winter coating

160m antennas

The main antenna for the 160m band is a 39m high vertical. The antenna consist of 29m of WIBE tower sections with an insulated base and a top tube which is 10m long. The antenna is tuned to 50 ohms through a tapped inductor which also makes the antenna DC grounded. The total length of radials are about 3km, each one alteast 1/4wl long.

The coaxial cable running out to this antenna is a 170m long RG-17 which has got a metal protective coating.

Here are some pictures of the antenna

The antenna from a distance, covered in snow

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