I have been using my Davis Vantage Pro2 weather station along with the Weather Display software since the start of January without serious issue. I also have not been on my HF rig much. I’ve noticed over the past few weekends when I did key up the mike for a short QSO that the Weather Display software had locked up. The computer is still functioning, to include UI-View32 but Weather Display freezes. After a little testing, it looks like this only occurs when I transmit on 20M at some point above 50-75 watts out. I played around with a few ferrite chokes on cables between the computer and my IC-7000, but it did not fix the problem.
I need to fix this problem. I can’t have my weather data locking up every time I want to get on HF.
This week I am going to tear apart the station and try to isolate the problem. I am also using the opportunity to put sliders on the legs of the table which will allow me better allow me to pull the table away from the wall when I need to get behind the gear.
Chances are your issue with the wx stn locking up isnt the cable between the radio and the computer but rather the power cable for the console of the wx stn and also the serial or usb cable to the wx stn from the computer. A couple of pointers if you dont mind:
Use mix 31 ferrite. If you cant find that use mix 43. Be certain of Mix!
Use a 2.4 inch toroid and wind about 8 turns. Keep first/last windings apart as stray cap will cause a loss of impedance in your windings.
Better still is a couple of sets of two cores wound like binocular windings. I use snap-its of mix 31 with no more than 3.5 turns per pair. With small wires the temptation is to use more turns but stray capacitance will eat at your impedance. I’d bet a fiver that a pair of binocular chokes on each end of each cable (power and usb/serial) will cure the problem.
A good write-up is in Chuck Councelmans whitepaper which is linked on my blog.
Best, Chas W7MAP/5
Chas – You are right! The weather station terminal has C cell batteries for backup. When I unplug the AC adapter and operate on 20M, Weather Display doesn’t lock up! This weekend I will use your advice concerning the chokes to fix the problem. I still think I am going to tear the station down to (1) fix my table legs and (2) do a neater job with all my wiring. Thanks again Chas!