The 144 Mc IARU September contest
Once a year PA6NL is active on 144 Mc, during the September contest. This is the most challenging contest for our group, because we do not have a "fixed" sation set-up like on all other bands. So for our experimental members (and fortunately the others as well) it is always great fun to see if we can put a working station together again.
The famous contest preparation
As usual we gathered at our sunny terrace around 12.00 local time.
From left to right
Ron, DL3BPC, Gert PA3BZZ and Ian PA4ZP are still missing. They joined later.
It's only one band, 144Mc. so why hurry .......
Building the station
Around 13.00 we were at the gate, waiting for the keeper of the building.
In the distance you can see the tower where it all will happen.
It was a bright sunny day. Temperatures were around 26 C.
It's hard work getting all our stuff up in the tower. Gert (front) and Ian are collecting sweat while bringing everything up.
After this ramp they still had 4 floors to climb..
Left: Hans giving a helping hand.
Hans, Remco Ron and Frank in deep conversation how to get a working station in the air.
We faced lots of interface problems and certainly needed the soldering iron to "glue" everything together.
It's always a challenge to get a working station within a few hours...
but great fun!!!
Note the sweat on Ron's T shirt. Thinking seems to be hard work...
It finally worked
Remco making QSO's using the East and West systems while Frank is still soldering to get the South sytem in operation.
It was added to the station after approx. 1 hour after the start of the contest.
A nice achievement, given all the interface problems we had....
Note the amount of wires going down. Who ever said radio was wireless??
The PA table
There are three PA's, one for the East, South and West antenna system.
The water cooled PA in the middle would not survive the contest.
The flow of cooling water was interrupted after a few hours. Although the PA just kept on producing rf it gave a lot of smoke at the same time.
The PA got so hot that the solder inside was melted and the stator plate of the tuning C was displaced.
More severely though : the waterhoses melted as well!!!!
The cooling water cascaded from the table just in front (!!!) of the HV power supplies on the ground.
We were VERY lucky this time. The PA was replaced with a spare one, but the whole station had to shut down for a while in order to get rid of all the water.
Remco tuning the spare PA
This was just one of the PA failures.
The 230 V inlet of a HV power supply got so hot that the 230 V was effectively disconnected.
The PA tripped and the protection circuits became active.
All fuses were OK. It took a while before it was found out that the 230 V plug was causing the trouble.
So once again less QSO's during that hour. (but at least we had some serious work on our hands again..)
The "new" PA had difficulties also. It produced barely 200 Watt.
Remco took it apart for a close examination, but all this work did not result in higher output.
The reason for the "smoke disaster" ..... A well maintained water circulation system.....
The green hoses were not suited for use with warm water. They collapsed and effectively shut-off the flow of water.
We need some modifications here next time...
The backside of the PA table.
A nice mess of wires and waterhoses.
There are some HV wires in between as well...
The antenna systems
Assembling the antennas.
Ian (front) and Remco busy mounting the antennas.
We use 12 antennas (3 stacks of 4) so they were busy for a while.
Our antenna take-off to the West And to the East
We are only a few hunderd meters away from the Northsea coast so have a nice take-off to the West.
We worked quite some GM, GW, GI and EI again. All with very good reports.
Contest after talk
With over 900 QSO's, a best dx of 1444 km, OH1NOR, and all our stuff back in the cars, we were pleased to have our traditional after contest diner at around 18.00.
Countries worked :
PA, ON, LX, G, GW, GD, GI, GM, EI, DL, OZ, LA, SM, OH, SP, OK, OE, HB9, F, GU.
The score :
884 valid QSO's with a total of 328558 km.
Average approx. 370 km/QSO.
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