Towers and Antennas

antennas aerial viewantenna-map

Tower 1 (M1)

Tower 1 (M1) is 105 meters high (344ft) rotatable tower. It holds 20M and 80M yagis.
On 20M antennas are 4 stacked 6 elemement yagis. Each 20M yagi has boom lenght of 18 meters (59ft) and stacking distance is 24 meters (80ft).
On 80M antenna is 2 stacked 2 element yagis. 80M yagis have also boom lenght of 18 meters (59ft) and stacking distance on 80M is 43 meters (141ft).

 Tower 2 (M2)

Tower 2 (M2) is 60 meters (200ft) high rotatable tower carrying antennas for 40M – 10M.
On 40M there’s two stacked 2 element yagis and for 20/15/10M there’s six stacked 10 element tribanders.

Tower 3 (M3)

M3: 60m
3*10/6
12/6

Tower 4 (M4)

M4: 60m
3*40/2
3*15/6
17/6
30/3

Tower 5 (M5)

M5: 42m
DP 160/80
40/2
20/5
15/5
10/5

Tower 6 (M6)

M6: 32m
DP 160/80
40/2
3*tribander

Tower 7 (M7)

RADIO ARCALA MAMMOTH 160/80M BEAM IN A NUTSHELL

If you want to build an Arcala Extremes (OH8X) style beam, you should start with measuring your property lines. Each of the four guy wires extends 120 meters or 400 ft from the tower – representing an area of 170´170 meters (550´550 ft) for a needed total space of almost three hectares. And then be ready to order needed 450 meters (1500 ft) of heavy duty tower sections. And finally make it look nice with 600 litres (120 gallons) of paint! Ready for the latest story from frozen Arcala deep North?

Height and weight of the system

Tower height 100 m (330 ft)
80 m beam 90 m (300 ft)
160 m beam 80 m (270 ft)
Total weight 39 600 kg (80 000 lbs)

 Elements, gain and take off angles

160 m 3 elements, 12.9dBi, 26°
80 m 5 elements, 15.7dBi, 12°

FronttoBack ratio

160 m 20-30 dB
80 m 20 dB

Operating frequencies

1810-1845, 1845-1880 kHz (SWR < 1.6)
3500-3560 kHz (Lmatch)
3700-3800 kHz (50 ohm / current balun)

160 m elements

Weight 1600 kg, (3800 lbs), each
Length 59 m (190 ft), all elements 12m (36ft) capacitive hats
Each use 700 m (2100 ft) of tubing
Tuned with 06 µH coils at the centre
Relayswitches for turning the ant 180°

80 m elements

Length 46 m (140 ft), longest
10 m from the 160 m antenna
max windload, 70 m/s.

Boom dimensions

160 m length 71 m (215 ft)
80 m length 60 m (200 ft)
The triangular 160m boom (2.2 m, 7.3 ft) comes with a rail for walking inside it.

 Turning gear

Weight 2000 kg (6000 lbs)
11 kW motor
Inverter driven softstart/stop

Largest guy ring bearing

Weigth 3300 kg
50 mm (2″) diameter balls in the bearing arrangement
Ring diameter 3,8m (13 ft)

Guy wires

Total length 2300 m (6900 ft)
Phillystran/element guys 1150 m (3450 ft)

Final touch

600 litres (120 gallons) of paint

Mechanical design and project Management

Tuomo Halminen, HALTA OY

Antenna design

Pekka, OH1TV, 160 m
Olavi, OH5BR, 80 m
Lauri, OH8LK, switching systems

Arcala team members busy at the project

Juha, OH8NC
Veijo, OH6KN
Martti, OH2BH
Toni, OH2UA

Group working on the project of their lifetime

Toke, OH6RM
Pekka, OH7RM
Markku, OH8SR.

The construction is capable of handling ICE and SNOW for its own weight. In an ice storm? God Bless Radio Arcala!

Hats off to Markku, OH8SR (left), Toke, OH6RM and Pekka, OH7RM.

Truly, these are men of iron!

M7 tower rotated