hf aerial taps

Up to 1000kms use 1mhz for every 100kms.
Each extra 1000kms add 2mhz to the above.
Add 2mhz for daytime or subtract 2mhz for night time.
In the medium time (between 3pm and 9pm) dont subtract or add the extra 2mhz.

Examples:
200km = 4mhz for daytime.
1000km = 12mhz for day time.
2000km = 10mhz for night time.
2000km = 12mhz for normal time.

Hi qubert,
Not the simplest thing to do as these frequencies are all calculated at the time of manufacture and depend on a range of factors. Once mfrd, it's a search-and-try method to find the points.
If you are going to tackle it, you will need a SWR meter (one suitable for HF frequencies, not your common UHF one) and a resonance meter, such as a grid-dip oscillator and a frequency counter.
Unless you have those items at your disposal, prob not much point in describing the lengthy procedure.
Otherwise, email me at
gezza90 at amnet dot net dot a u
rgds
Gerry

The frequency distance eh ? As others posters have said, not as simple as you think. It depends upon such things as dia and pitch of the wiring etc etc etc. I'd suggest you borrow an antennae analyzer and use that to get it right, mounted on the vehicle of course.