As a better and even safer solution, Use LiFePO4 cell x 4 pack for no mote than 14 Volts from the pack. . Fully charged each cell is 3.3 to 3.5 volts. At 2.5 volts they are depleted. This type of Lithium rechargeable us also far more tolerant of overcharging and overdischarge than original LiPo technology. It is far less prone to catching fire or exploding with physical or electrical abuse It is a little more expensive, and not quite the same power density as regular LiPo, but still beats Lead acid.
I use these for my K2 and KX1 with good results. Chip AE5KA On Thursday, January 12, 2012, Vic K2VCO <[email protected]> wrote: > Would it work to use 4 cells with a couple of series diodes to reduce the voltage? > > On 1/12/2012 1:49 AM, rolf wrote: >> Elecraft specifies the voltage supply range for the K2 transceiver to 9-15 >> Volts. >> >> This range is suitable for lead or nickel batteries. Using Lithium >> rechargeable batteries it gets somewhat problematic. The voltage range with >> a single Lithium Ion (or Li-Polymer) Cell is from 4.2 V (fully charged) to 3 >> V (lower limit). Using in a power supply battery pack 4 cells in series, >> the voltage ranges from 16.8 V (max) to 12 V (min). With the K2 as a load to >> the battery pack the maximum voltage drops fast down to the plateau voltage >> of about 14.5 V. The upper voltage of 16.8 V, however, exceeds the maximum >> supply voltage as given by Elecraft. >> >> Using 3 Lithium Cells in series, the voltage range will be from 12.6 V to 9 >> V. This is within the specified supply voltage of the K2. However, this >> voltage range is not very suitable for getting the maximum RF output. >> >> Question: Keeping the RF power output and the DC Current of the K" below the >> maximum limit, is it possible to apply a supply voltage exceeding 16 V >> without causing a failure to the electronic components in the K2? >> >> Especially for portable operation the use of Li-batteries reduces the weight >> in the "rucksack" considerably. >> >> Any answer is appreciated. >> >> Thanks and 73, Rolf, DL3AO >> >> >> >> -- >> View this message in context: http://elecraft.365791.n2.nabble.com/Supply-Voltage-Range-Elecraft-K2-transceiver-tp7179694p7179694.html >> Sent from the Elecraft mailing list archive at Nabble.com. >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html > > -- > Vic, K2VCO > Fresno CA > http://www.qsl.net/k2vco/ > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
