sorry for my bad audio on 20m during the activation of the OK/PL-031 on Sunday. I used this time Yaesu FT-100 (70% of max. HF power = 60-70W out) powered by SLAB 12V/22Ah and inv-V antenna. The reason of the distortion was low battery voltage and maybe also low temp -6°C on the summit. Power consumption of the FT-100 is very high and also my battery is old… It seems the FT-100 is sensible on the power source voltage.
However I enjoyed the activation well. Thanks a lot for the very strong pile-up, specially on 40m, I made there 71QSO in 37min. Also 20m was successful. I made there N1EU, W4ZV and N4EX, where the N1EU was really 59+20dB!
Also the next activation of the near-by summit OK/PL-041 was nice. Although I used only QRP from my Yaesu FT-817, the pile-up was also nice and I made N1EU and N4EX on 20m again. Thanks for it!
Yes, I also have an FT-100D and have read and experienced that the radio will distort on SSB if the supply voltage drops below about 11.7V.
I have not been able to run on a 7AH SLAB for more than a few minutes at 50W and have still had some difficulties at that power level with a 10AH LiFePO4 battery. With power levels between 20W and 30W things do seem to work Ok with the LiFePO4 on SSB - I had a four hour activation yesterday at those power levels (mostly CW). The FT-100D is perhaps not the best radio for SOTA, but it can work.
In reply to K7ATN:
Etienne, thanks for the confirmation, that the problem was in in low batt voltage.
I know, FT-100D is not a good SOTA radio, normally I am using only my FT-817. I wanted only to test the difference between real QRP and “low” power (60-70W)
