Actually, the 40% Tx duty is only 50% key down (there's spaces betewwn the elements). So, you use .2 for the Tx factor. .8 Ir + .2 It = .24 or 16 hours.
Now, after you work the 9 hours, you might fall over and hit your head on the key, and then the CW duty cycle goes to 100%. But the Tx duty cycle would go to 100% also, and you'd be off the air sooner. Not that it matters much as you are napping on the key<g>. Dan / WG4S / K2 #2456 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of John R. Lonigro Sent: Friday, June 11, 2004 10:39 PM To: Elecraft Reflector Subject: Re: [Elecraft] K1 Battery Question John: Here's my guess: 1) Measure the receive current in Amps (Ir). 2) Measure the transmit current at the power level you plan to operate, in Amps (It). 3) Estimate your transmit duty cycle, which will usually be quite a bit less than 50%. 4) Compute average current drain (I). Assuming a 40% duty cycle, your average current drain (I) would be 0.6 x Ir + 0.4 x It 5) Divide 4 Amp Hrs by your average current drain and that will give you an estimate of your time with the battery. I don't have a K1, but the spec says as little as 55 ma on receive, so assume 60 ma (0.06 Amps). If your transmit current is 1.0 Amp, then with a 40% transmit duty cycle (probably high), your average current drain would be 0.6 x .06 + .4 x 1.0 or 0.44 Amps. With those assumptions, your fully charged 4.0 Amp Hr battery should last about 4.0/.44 or 9 hours. A 40% duty cycle might be equivalent to continuous heavy operating during a contest. John AA0VE John J. Bahun wrote: >I have a 4 Amp Hour Gel Cell pack that I just acquired. I was wondering if anyone has any input as to how long I should expect the K1 to operate off this battery with typical transmit behavior (Not sure exactly what that is...) > >Thanks > >JB - WB8UFA / 7 > > > _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
