I C 8 P O F
Ultrabeam yagi antenna UB620 3elements
maintenance report
3...-- repainting : given the impossibility of treating the fiberglass in a safe enviroment, I decided not to polish the tubes . 4 ....-
In november 2020 I have had the opportunity to buy a ten years used UB620 yagi antenna.
Poles had the fiber degraded by sunlight and salty humidity being near the sea
the black ones are 10 years old.
The transparent ones are two years old have also a degraded surface; they have been changed by the
previous owner after a rupture due a strong wind.
new painting"
Just painted over two times with a green color.
*** but remember to use handgloves to handle them.***
-->> ground testing
.....
the red circle indicates a lost screw, read below ...
the tapes and the sliding contacts are all ok
-->> severe burn
-->> rebuilt point
-->> oxidized&cleaned
...
...*
the running tip has been rebuilt.
the SIDOL cleaner removes the oxidation and burns and cleans very well the tapes.
has unscrewed itslef leding to a little water infiltration that caused some oxidisation
and on the radiator box one screew lacked at all.
1 link to larger pic ->
2 loose screw
3manca vite - lack of screw
due to bad blocking nuts, therefore I had to change all with new ones.
the yellow circled screws are the WARRANTY state indicators that most be carefully cut to open the motor-boxes.
-->>boom to plate oxidation
the severe oxidation between the aluminium boom and the inox antenna holding plate has been cleaned and NOALOX paste has been put.
all the buttons were not centered in the front panel holes anymore so they did block at every pressing
therefore I had not only to move the internal pcb for a better alignment, but I had also to file some holes
to let them be centered in them for a better working travel.
,,,1
....
-.-
......filing few tenths of millimetre to get centered the buttons
front panel removing, using a cutter pay attention to not damage the panel.
yellow dots indicate where have been filed few tenths for better buttons moving
I had just a little fear about a new cable entering into the shack for possible RFI, but untill now more that one year later I have noted no RFI.
this motorized project is very fine and the 180° direction inversion is a must have.
Any improvement or suggestions will be appreciated,
Write to my to my email on ic8pofATyahoodotcom (copy,paste and correct)
.
dic2020, gen-apr22