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Replacing a Steppir coax cable is an easy job i thought

Steppir down for coax replacement.
To replace the coax i needed to bring the Stepper complete down.



By coincidence  the same afternoon we had a thunderstorm
A so called supercell caused a lot of damage 25km east of me
 here Luckly only short time strong wind and a shower rain.

Supercell 27-6 Oude Pekela
The plan was to replace 30m H100 with 25m RF400 low loss flexible cable.
An easy job should fix it in the standing lowered mast in an hour or so....
But this took me all afternoon and part of the evening.
RF400 is "the best coax in this diameter 9.5mm"  I used PL259  connectors of a higher quality
This type is for semi-air or foam cable like RF400 but i first did not know what the "extra" ring is for.
Afterwards i found that it should be over the braid against the gasket, then the braid must be clamped between the 2 rings the The opening of that ring is too smal to fit over the outside but does go over the bread.
The lower ring bus is pressed into the cable under the braid.
When i checked the cable galvanic without the extra ring it seems okay, but an RF test with dummy gave high SWR. 1:4.7
So had to do it over again ... back to the workshop...

The lesson was again : test everything even the simple things..


3 rings do not forget the small one in the middle as i did  not know what its function is



Had to cut off 3mm bus to fit to the SO239 female  that is not extending enough.
Some SO239 are too short, especially if the SO239 is placed inside.. as in the STEPPIR EHU.

Another detail can be seen: the nut is completely turned in, because here the extra ring was not used. Normally this nut must be fixed with reasonable force and wil not completely close a small gap must be left between nut and connector bus.
STEPPIR E.H.U.  Almost impossible to connect a cable even with 2 hands free at ground level.
I first tried this at 8m a.g. but simply impossible position and the connector will stay loose from the serrated edge it should lock on position. 
 The engineer  must be a sadist... 
But the STEPPIR is working fine without any issues since last year when i finally set it up it did not make faulty  steps while the control cable is 60m # 200 feet
also the coax to the set is about 55m "low loss"  but still loss 1-2 dB    



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