Councilor: LOL if you are looking for precise information from imprecise data. Best I can do is a WAG. If you take your ah rating say 36 and multiply by the battery voltage say 12, we have 432 watt hours. Divide by 2 to account for efficiency losses and we have 216 wH and finally divide by your transmit draw 80 watts and we have 2.7 transmit hours. Does this help? Remember this is a WAG (Wild Assed Guess). 73 Fred, AE6QL
-----Original Message----- From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Esquer Dave Sent: Tuesday, March 29, 2016 1:42 PM To: elecraft@mailman.qth.net Subject: [Elecraft] Battery requirements for NPOTA activation with KX3/KXPA100 Hi folks, I know this has been asked and discussed before but I can’t seem to get a handle on a clear-cut answer … I am going to do a SSB NPOTA (National Parks on the Air) activation with my KX3/KXPA100/PX3 on battery power. It has been in the works for a while with a special use permit required by the NPS. How much battery capacity do I need if I want to run full 100 watts? For planning purposes, I am assuming a 6 hour activation with a (highly optimistic I know) 60 QSOs per hour. The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do just fine. My concern is the amount of draw I will need to last the 6 hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a QSO. The QSOs varies between 50-80 watts on transmit. I also know that once I am spotted, I can drop the power down to maybe 75-50 watts to save some battery juice. I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered? If you have any real-world experience or tips, it is most valuable and appreciated. You can contact me offline at dave dot esquer AT gmail as well. Thanks, Dave, K6WDE ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to fptowns...@earthlink.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
