Topband with its wavelenght 160m is not very easy band. Dimensons of antennas are extensive. For MW9W contest crew I have prepared simple but effective antenna for 160m – the Inverted L antenna. It’s based on the material DK5WL „Invisible“ DX Antenna for the Low Bands.
I bought two fibreglass poles with total height 12,5m and prove the antenna in the IARU HF Championship with impressive result. Try it too!
The Inverted L antenna is simple quaterwave antenna with a shape of inverted L letter. Most transmitted energy is vertically polarized. That’s an advantage for DX contacts.
|
|
Read more...
|
|
Are you using a cheap antenna rotator like AR-300? I have three these rotators and on one I have found a difference between the real antenna azimuth and indication. After few hours was the difference 80 degrees. Rotator, especially rotator with a top bearing is constructed well and could be used also with a larger antenna as a HF monoband yagis for higher bands or smaller tribander.
I have developed simple antenna azimuth indicator – aziumth measurement. It’s a simple Wheatston’s bridge where is used a pot attached to the rotator tube as sensor. Voltmeter is showing directly azimuth in degrees from 0 to 360.
|
|
Read more...
|
|
The multiband Windom antenna has been described in 1929 by W8GZ. In the HF amateur community is very popular FD-4 antenna. It’s a simple wire antenna for the most popular HF bands. DL1BBC has extend the available bands of FD-4 antenna adding two wire radiators. The result is an 8-band antenna for bands from 80m till 10m.
The new radiators are 4,69m and 9,38m long and are connected to the balun 1:6 and going down to the earth. The angle between both wires is around 100°. DL1BBC and DJ7SH have built and prove this antenna with a good results.
|
|
Read more...
|
|
When you run more than one station in the multi – multi cathegory you might experienced a receiver overload problems. Antennas are too close to each other and running high power could damage receiver nor overload it!
We have developed coax notch filters which performed well in MW5W last year. It’s a K2TR design – easy to built, not very expensive but really effective.
|
|
Read more...
|
|
USB tester is a simple probe that checks if you have connected the frame with an USB connectors to the mainboard correctly. Many joints in the computer world can’t be plugged wrong except these plugs. And if got an old motherboard for few bucks without any documentation it can be dangerous to plug any USB device incorrect. This USB tester check the polarity of voltage. If it’s correct, the the green LED is lightning, if not the red LED is lightning. See the schema for explanation.
|
|
Read more...
|
|
|
|
<< Start < Prev 1 2 3 4 Next > End >>
|
| Results 1 - 9 of 29 |
