Our mistakes this time
We just don't learn !!
Faulty 9 cm connection
The 9 cm transvertor and TWT side by side on the roof. The transfer relais switches between the the dish and a 23 el Tonna antenna.
This way all 23 cm transmissions can continue via this system while using the disk for 9 cm.
Hans PE1CKK, our roof expert, was not present during Saturday, so lots of things needed to be re-invented.
We like people with a drive for results. The goals was : connect all cables, which has been done.
That the sequence of these cables is of some importance as well was momentarily forgotten....
The final result was a bad SWR on 23cm and 13 cm.
After some investigation it turned out that the 9 cm transvertor has been trying to absorb all the 23 cm power. The 9 cm transvertor was dead, even before the contest was even started.
Yippee, we had the first real work on our hands. (QSO's are sometimes SO boring...)
Henk PA0C busy with the repair of the 9 cm transvertor. It turned out that the pre-amp had had difficulties in absorbing the power of the 23 cm PA.
No gate voltages could be measured anymore.
The pre-amp was removed for closer examination of the damage.
The first stage of the 9cm pre-amp showed quite some damage.
The gate was gone and so was the rf-choke on the PC board.
After 15 minutes the pre-amp was repaired and we were operational again on all bands.
The QSO with DK2MN on 3cm took quite some effort. We could copy him fine, but he did receive us only 419. A sked failed, so what was wrong here ????
South is were the sun is highest around 12.00, but this seems to be difficult to remember. The dish was mounted 180 degrees wrong on the rotator, so we had made the QSO with DK2MN on the back-side of the dish. No too bad anyway....
After a 180 degree re-alignment of the 6, 3, 1.2 cm mast we finally were in business.
6 cm trouble
It was amazing. We could copy stations very well on 6 cm, but they could not hear us. Something that was quite unusual.....
We managed some QSO's with relatively local stations, but found the difference in sent and received signal strength quite high.
There was definitely something wrong here !! The 6 cm transvertor was taken down for a closer look.
Below left : Ron, DL3BPC, measuring the output of the 6cm transvertor. It was only a few milliWatt. So also here some more investigation was needed.
Right : the 6cm transvertor open for inspection. The drive power was OK. Notice the big smile on the face of Ron. He enjoys having some REAL problems again !!
It was found out that possibly a loose connector at the relay had caused the trouble. No real fault was found and all worked fine during the remainder of the contest.
Last week it still worked OK on the airport, but during the contest it gave the message : "device unavailable".
This simple message meant that we could not be QRV on the internet, dx-cluster and converse.
The dent in the PCMCIA card caused a short circuit at the connector which inflicted irreparable damage.
This cards only future is the trash can. Pity...
The west rotor would not move beyond 260 and 320 degrees. Loud hum and crashing sounds were coming from its interior. The mast was already up, so Henk PA0C climbed the railing and gave the rotor a good bang. It worked OK ever since.
We definitely need to take this one apart one of these years, otherwise it won't last....
What we all hope for....
Let's hope we ONCE have a contest in which no failures, burn-outs, etc. take place. It would be quite an achievement for us....
However, it would take all the excitement and fun away. We'd better leave it as it is....
The station for 23, 13, 9, 6, 3 and 1.2 cm
Work on the roof
The junk we operate with... An impression of all the (very) old stuff we use.
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