Re: Power and SWR reading are wrong on upper bands.
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Made some SWR measurements with NanoVNA. Red is with ATU powered on, Green ATU powered off.
On Fri, Aug 19, 2022 at 4:22 PM Petronel YO8SEP < yo8sep@...> wrote: Hi,
I just received my ATU-100 from Banggood and I did some testing with KX3 and a good dummy load. First I've changed the EEPROM cell 05 to 01 (min power to 1W), and Auto tune to 0. When I TX on 50MHz band, with 10W from KX3 on a 1.0 SWR dummy load, the ATU is showing almost 4 SWR and PWR of about 6W (this is with 0 L/C). If I tune, it will bring SWR to 1.45 on display but KX3 will show a SWR of 3.0 This will happen till freq is down to 7 MHz (see attached image)
I plan to redo the tandem match for a 1:5 ratio. The problem might be from the tandem match or from the diodes ? The marking on diodes seems to be "B66" or "866".? Should I replace also the diodes with BAT41
73, Petronel YO8SEP
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