24 June 2014

Excalibur 2 Project. The grass is mown

Paul AA4XX has now spent time mowing the site. It looks fantastic. So now onto the shack clearing!

22 June 2014

Excalibur 2 Project. Grass cleanup

Saturday and Sunday mornings were spent using a large rented weed eater to tame the small bushes, weeds and grasses at Excalibur. The weather was favorable today Sunday with a light misty shower in the air. I used a carbon tipped blade on the end of the weed eater to cut down the small bushes.

Next I will start on the shack clearing operation.

16 June 2014

QRP Project Enclosure. Concept design. Greg Hayter

My son Greg, who is an Industrial designer by profession, drew these quick sketches. We are thinking about investing in a sheet metal bender, shear and brake machine for making home brew enclosures. The sketches show, amongst other features, the idea of bending a single sheet of metal for the case sides with a single join.

14 June 2014

Excalibur 2 project. Antenna cleanup

Today I began to clean up the radio site at my friend Paul's (AA4XX) farm. This site is affectionately known as 'Excalibur'. This name stuck when we first deployed a 5 element full size beam for 20 meters. The tower was struck by lightning about 2 years ago. This started a fire in the shack causing internal damage to the shack. Luckily the exterior of the shack survived and is in excellent condition thanks to a coat of paint that Paul and his son gave to it.

I began by clearing away all the wires lying about the area. Many of these wires have been on the ground for the past 2 or 3 years and are thus embedded into the ground.

I also pulled down the existing remains of the wire antennas. These wires were deployed using weed eater plastic cord. Interestingly after 3 years this weedeater plastic is still very strong and does not appear to have deteriorated at all.

Much of the wire was from a topband radial system that Paul deployed. These radials consist of aluminum fence wire and is excellent and inexpensive for antenna applications.

Aluminum home brew wire feeder. Still in good condition and will be redeployed.

Recovered wire and cord from Excalibur site

03 June 2014

Calculated attenuator return loss using practical resistor values

I was interested to understand what the Return Losses would be when using 1% tolerance resistors for fabricating attenuators. 

The 20dB attenuator shows the worst Return Loss.