Not all baluns are created equally....... below you can see the size difference between a Comet CBL-2000 supposed 1:1 current balun with a 2KW rating for SSB and next to it a DX Engineering, a little futher below a picture of a Baluns Design 4:1 balun.

DXE-BAL050-H10-AT 1:1 current balun with a rating of 5KW - 10KW. The DX balun is specifically designed for use with an ATU. I’m using this one with the doublet antenna.




Taking a closer look at the DX Engineering balun reveals a very beefy construction.


Below is another comparison - this time with a Baluns Design 4:1 balun, I’m using this one with the 40m loop.

balun designs and Comet



balun designs


A similar observation has been made regarding feeder cable. The 300ohm cable on the right sold by most of the UK radio suppliers features 7 stranded cable. The 300ohm cable on the left bought directly from DX Engineering in the USA features 19 strand 18awg with a velocity factor of 0.88.



A very useful antenna accessory recently purchased (also from DX Engineering) has been some ladder line standoffs - these really work well by a) maintaining the integrity of the balanced line, and b) providing a very neat cable run. Here follows are some pictures of how I have used them at my QTH. (The spacer is seen in the first image at the top right)

 


 

 

 


 

The products above - the balun, ladder line and accessories were purchased directly from DX Engineering - this was the first time I had used them and have to say I have been pleased with the transaction. Their service was resonably speedy and their products appear good value as well as being quality. I conducted some tests comparing the SWR of the DX Engineering and Comet baluns and found the SWR rises with frequency with both of them; the following is a table of my findings.



SWR Readings
Frequency Dummy load only Comet CBL-2000 DX Engineering
1.8 1.0 1.0 1.0
3.7 1.0 1.0 1.0
7.1 1.0 1.0 1.1
10.1 1.1 1.1 1.2
14.2 1.1 1.1 1.2
18.1 1.2 1.2 1.3
21.2 1.2 1.2 1.4
24.9 1.2 1.3 1.5
28.5 1.2 1.5 1.6


The dummy load is a Palstar DL1500, and in the test I was using 100watts.

© m0mrr 2021