On Sat, Apr 19, 2025 at 01:16 PM, Mark Lunday, WD4ELG wrote:
with a freshly charged 9 B Bioenno battery
Mark, a freshly charged "9V" Bioenno battery will have an output voltage significantly higher than 9V.?
From the Bioenno manual, its nominal voltage is 9V, but its charge voltage is 11.1V.? After some amount of running discharge time, which decreases the 'full charge' value to the steady state value, quoting from the manual, "The battery outputs a steady voltage around 9.6V until very little capacity remain".
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So you were likely running your QMX at significantly higher than the recommended voltage for a 9V build.? If you run FT8 at this voltage level, it may result in damage to your finals.? CW and SSB may survive, but there is risk.? You should put a simple silicon diode in series in your data cable to drop the voltage by about 0.6V to be safe.
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I am not surprised that you had some problems; I'm not sure why a bunch of Factory Resets fixed it.
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Stan KC7XE
