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QRV from 80 metres through to 70cms on SSB / FM / DSTAR and DMR . I have to say that I like the way DMR works over DSTAR, (once you have done your code plug of course) 

 

New antenna setup. Same amount, just a different configuaration. The horizontals for 2 and 4 metres are Innov antennas OWL's and the verticals on the crossboom at the top are Wimo's. (I like the WIMO's because they have a built in balun and N socket. the 2 Metre one is amasingly light)

The Innov antennas are sturdiliy built, especially the 2 metre one. I do have reservation though about the direct feed point sealed off with rubber solution and the fact that the balun is a separate purchase. The balun is a choke type and quite heavy, so I took the step of securing it to the boom with a stainless steel jubillee clip.  Time will tell how the feedpoint stand up the the elements. Another reason why the WIMO's are on the top.

I decided to go for a crossboom because the vertical section of the old cross polarised antenna was always affected by the coax running down the fibreglass pole from the 70cm yagi above it. The SWR on both verticals is now fine. 

 

 

New antenna lineup

 

 I have also taken the step to tidy up (I use the term very loosely)  from the original setup, by moving the rotator to the bottom of the mast. A far cheaper alternative to a proper bearing and rotator cage. (I'm not sure how novel an idea this is, but if it's a first, I claim the design rights. LOL)

 

 

 The mast itself now runs through a steel tube lined with some rolled up plastic sheet (the type used for covers on ringbound documents) to prevent metal to metal contact and take up some free play.  The tube is held in place by 2 "K" brackets. There is a ball race thrust bearing that sits on top of the tube which is held in place by a collar, which takes nearly all the downward force. Time will tell if the setup is durable, but the weight in the air has been drastically reduced.  The intention was to reduce the visual signature, and take the radial load off the rotator, which it has actualy been putting up with for at least 17 years. Goodness knows how old it is, because it was well used when I acquired it. Its new position also means that replacement or repair is now a one man job

 

Many thanks to Alan, M0DNU, without whose help and brute force,  this could not have been achieved. He also doesn't mind standing on the roof. 

 

Below is the old setup

HF antennas. From the left,a G5RV supported on a fibreglass fishing pole with feedpoint at around 12 metres above ground. Unfortunately,not enough room for a flat top. A 17 metre dipole and a G7FEK for 80 and 40, which for interG and near contineltal is often down on the G5RV but occasionbally outperforms it. The G7FEK outperforms everything on 20 Metres though, not sure why, but it has a very low noise floor on it. 

 

 

Here before you is oine of those cheap N connectors which use a bevelled collar rather than a 'Top Hat' compression ferrule which slides down in between the sheath and the braid. As you can see rubber (as opposed to synthetic gland which is used on the quality connectors) has perished causing the connector to fail . Lesson learned. Never use this type again. As the saying goes. Buy cheap, buy twice.  I've had proper ones up in the air for nearly 17 years, and they are as good as new, and have been re used on the refit. 

8473608 Last modified: 2017-11-25 13:32:36, 5059 bytes

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