Hi Luis, Markus, LF This is a very interesting topic for me too. My antenna resistance is very high, usually more than 100 ohms. I think there may be a few reasons. There are trees near the antenna w
Paul It's been my 'hypothesis' that as the temperature cools the sap heads toward the roots in stages ... not in one big rush. As the temperature heads toward freezing, sap first leaves the small bra
I would absolutely agree with Jay - and your comments Paul - proportional and differential - the trees react very fast to external temps and clearly seen on losses - The White Birch especially, my Co
Hi All, LF Interesting topic. Also happens in MF but in LF it gets more critical. Must be a nightmare at VLF :( As Marco explained, our setup is not the usual at ground level in a property plot. And
Hi All, LF Interesting topic. Also happens in MF but in LF it gets more critical. Must be a nightmare at VLF :( As Marco explained, our setup is not the usual at ground level in a property plot. And
Hi Markus, LF The pipe contains presurized water for the fire extinguish system. Is a "wet colum" system. Pipe segments are connected with big brass links. Should be a good enought current conductor.
Hi Luis, Am 27.10.2018 23:11, schrieb VIGILANT Luis Fernández: Hi All, LF Interesting topic. Also happens in MF but in LF it gets more critical. Must be a nightmare at VLF :( Here it is more c
Thanks Jay and Laurence for weighing in on this. Like many amateur radio operators I am not likely to have opportunity to take field strength measurements, though I wish I could. It seems to me it mu
Hi Stefan, LF I have an old thermocouple Amp meter, 4A range. Couldn’t check if calibration is correct but better than nothing Yes, the output waveform from PA is a perfect sine in the scope Hm
Luis you mention measuring at the end of 30m of coax. Presumably the loading coil is at the antenna?? In which case you need to check that you have not parasitic resonances at harmonics of the drive
Hi Alan, LF Thank you for your comments Yes, the coil is at the antenna, at the end of the 30m coax line. Attached is a sweep between 8 and 300Khz There is only one resonance at 137KHz as you can see
Ok Luis I remembered after I posted, that I think Andy's loading coil was indoors fed by short coax run to the wire. So the capacitance of the coax was across the link, or tapped section. Pure water
Ok Luis I remembered after I posted, that I think Andy's loading coil was indoors fed by short coax run to the wire. So the capacitance of the coax was across the link, or tapped section. Pure water