Saturday, 31 August 2013

Tek492P spectrum analyser

This is the TEK492P spectrum analyser I mentioned in my posting on the UK Microwave Reflector.
With 18-26.5 and 26.5-40GHz external mixers and Diplexer
Analyser covers to 21GHz on its Coaxial input.

- Posted using BlogPress from my iPad


Friday, 16 August 2013


Following our recent trip to the Isle of Mull for a few days break and to take up a long-standing invite to stay with friends on the island I have returned determined to get the EME system back on air. More on this in another posting.

First, Mull...... What a lovely place! Although we didn't see any eagles we did see dolphins, otters, red deer, puffins, assorted other sea birds and lots of herons.

Our trip across the island to Tobermory via Salen on a very narrow single track road was exciting and definitely a great way to see more of the island than many visitors see.

I am still enjoying the large piece of Mull Cheddar cheese bought at the Tobermory cheese farm!

We had dinner at our friend's, friends sea food restaurant, the 'Ninth Wave' near Fionafoort. Carla and John, the owners, did us proud. It was a very special birthday meal for my XYL! Fresh caught Lobster, fine wine and very tasty desert...........
The Ninth Wave,
Highly recommended.

The following day we took the boat to Staffa and then Iona. It was from the boat that we saw the puffins and then the dolphins. Unfortunately the puffins had pretty much left the island by mid August, but were observable at sea.

Fingals cave on Staffa

Dolphins feeding on the way back from Staffa

After a brief call back on Mull the boat took us across to Iona so that we could see the abbey and have lunch. Then the regular ferry back to Mull.

Benedictine abbey on Iona. The original abbey, built by St Columba, has been largely lost and the newer abbey built in its place. It's still worth a visit.

We left for home with the regret that we didn't have longer to spend in this fantastic place. I'm sure we will be back.

- Posted using BlogPress from my iPad


Thursday, 1 August 2013

Earthing the mast

Today I decided to connect a protective earth ( ground) to my Versatower.
This mast has been up for 11 years next month and in all that time I have not had a grounding system in place. I've relied on luffing the mast over whenever there is a storm in the area.
After a long chat with G3NYK and G4HUP about this at our weekly coffee get together last Sunday I decided I really had to do something.
Today was the day.

For now I am relying on a single ground rod. I will increase this to 2 or three in the very near future.
What has been the problem up to now is deciding how to connect to the metalwork of the tower. Although the round sections of the lattice would be a convenient place to make a connection, the fact that the mast luffs over means that a long ground lead would be required when new mast was puffed over. That is not a good idea. The ground lead should be as short as possible to ensure that the inductance of the lead is low. The rapid rise time of lightning discharges do not want to encounter a lot of inductive reactance.
I decided to drill a 9mm hole on one of the mast ground post locating 'pegs' and fit an M9 stainless steel bolt that would hold the ground lug on one end of the ground wire. These pegs are the nearest point on the mast to the ground beyond the concrete base of the mast. The locking pin prevents getting too close to the end of the peg, but near enough.
The photo shows two parallel ground wires. This is probably not a good idea and a single, large diameter, or flat, non-braided, ground would be better and will come later.
The ground rod is driven 4 foot into the (soft sand) and the big brass clamp is secured to the ground wire lug with brass M8 stud and nuts.
The black 'gunk' is an RTV sealant to protect the lugs and screws as well as the wire.


- Posted using BlogPress from my iPad