Juha, OH6XX and I spent 4 days at the station to make some changes with the antennas. Some time ago we bought a 20-15-10 meter triplexer with HP BPF’s from Ranko, 4O3A. To make the antenna switching more simple, we decided to go monobanders with the EU tower.
Last Thursday we took down the EU tribander stack and started to make 4 el OWA yagis for 20, 15 and 10. Kari, OH5LF came to make some modifications to the AC distribution network and the grounding of the station.
New yagis were completed on Friday and lifting up to the tower was scheduled for Saturday. Peter, OH5NQ and Kimmo, OH5KS came to help and the antennas were up in the tower in less than 2 hours.
20 meter yagi is based on G0KSC desing with re-modelled element tapering. 15 and 10 yagis were replicated based on 20 meter data.
On Sunday we ran a 135 meter hardline to the EU tower to complete the assembly. On 40 we have a 1/2 inch cable, on 20 a 5/8 and on 15 and 10 meters a 7/8 inch hardline.
Next time we will add some stackmatches, triplexer, BPF’s and 50 ohm switchable dummy loads together with 4O3A SAC X controllers to complete new antenna switching system.
Juha OH6XX at the tower
15 m 4 el OWA
20 m 4 el OWA at background
10 m boom assembly, OH5NQ and OH6XX
10 m 4 el OWA
OH5NQ and OH5KS
EU yagis up in the tower
Until the next time
73, Timo OG9X
We arrived the station on Friday evening and started to make a new
operating table for multiplier stations. We made a big shelf for the linears
Next step was to repair the antenna switching. We had a problem with
160 and 80 meter antennas. Since it was getting very late we decided
to get some sleep and continue next morning.
Kari OH5LF and Kimmo OH5KS came on Saturday morning to fix the rotator
of the big 62 meter tower. The tower rotates OK, but the EA4TX control
box is burned and has to be replaced. Fortunately we have a possibility to
rotate the tower with a remote switch.
Juha OH6XX and I connected high band EU antenna back in business so
that we have 3 directions on 40 – 10 meters.
In the afternoon we replaced the broken coaxial for 40 meter stack.
After the sunset we continued with antenna switching. Finally the
problem was found and we got it operational again.
In the evening we participated The Polar Battle, Scandinavian Activity
Contest for a few hours with about 550 qsoa logged.
Now we are ready for CQ WW SSB contest. We will operate as a M/S
with 6 operators.
73, Timo OG9X
A week ago Juha OH6XX and me went to the station on Friday evening to make repairs after the thunder storm. Mikko OH6HZH joined us and as it was CQ WW RTTY contest weekend his intention was to work the contest part time.
We assembled the fixed stack matches for 40-10 meters and they seemed to work OK. We still have some problems with antenna switching and we could not route antennas for 80 and 15 to the station. That we have to look again next weekend.
Kari OH5LF came on Saturday to change the chain for 62 meter tower just to find out that the motor was burned and there was also something wrong with the gear. The azimuth indication potentiometer was also burned. He will come back next weekend to repair the rotating system. We also noticed that the EA4TX rotator control was not working. There were 2 burned fuses and it seems that the -12 V power supply was damaged.
Tried also repair the semi-automatic amplifier for 160-10 m. We thought the problem was with a time-delay chip which was replaced but could not get it working with automatic band switching. Have to look that again next weekend. Fortunately we can use it as a manual amplifier.
We made new phasing lines for 20-10 meter EU stack and replaced them. While checking the SWR of the stack we figured that the stack match was broken. OK, one more broken box to the to do list.
We took a walk up on the hill to check the beverages and found NA beverage being broken in 3 places. As we have very limited time to make repairs at the station it seems that we have to work CQ WW SSB contest without RX-antennas.
We will update after next weekend
73, Timo OG9X