Hi Paul, Thanks to you, too. Your comment on160m confirms my suspicions.
’m going to take a careful look at the ALC and see if I’ve got that right. Does anyone know how to entirely disable ALC on a FT5K? Or, is this just a dumb idea? 73, Ed W1KOK I am surprised and pleased that this question has generated so much response. I’ve been puzzled by this all winter as I struggled with running 5 to 10 watts on Top Band. That said, it’s amazing what can be done, including numerous EU, AF, SA and VK/ZL contacts, with so little power on 160m! > Start-of- transmission power spikes will almost certainly occur on any radio > which is using traditional alc to control output power. Spike severity is > directly linked to the amount of gain reduction the alc is giving. For > example, a 100w rig with power output reduced to 5w using a power control > which operates via the alc system can be almost relied upon to produce 100w > spikes at start of transmission. No brainer. > > The best way to avoid spikes in any rig using FT8 is to carefully adjust > audio drive level in the software until desired power output is obtained > without the rig applying any alc at all. In this way overall system gain is > only sufficient to produce desired power and no more - so spikes are > eliminated and you get a cleaner transmission. > > That said, I say again that I can exactly reproduce this problem at will on > 160m where my antenna system clearly puts large voltage onto the cable > between the pc and the rig. My interface uses industrial quality logic > isolators for civ and ptt together with audio isolation transformers and > dozens of ferrite rings on tuner - rig - pc cables. RFI still gets through > and kills the usb connection on 160m. To cure this I will rethink the 160m > antenna which I suspect is the easiest way. > > Regards Paul G3NJV >
_______________________________________________ wsjt-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/wsjt-devel
