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In article ,
Barrett wrote: Can some one give me an idea on how long these 2600mA should last in the MFJ-259 when left on without turning off? One manufacturer's data writeup (for the Twicell batteries) says "The amount of electricity which a [NiMH] battery loses through self-discharge at 40 degrees C in one day following full charge is approximately 5% of the rated capacity." If it lost this same percentage of its total charge every day, the battery would be completely self-discharged in about three weeks. If it lost 5% of its current charge level per day, it'd be down to 50% charge in a couple of weeks, maybe to 25% at the end of a month. Even if the self-discharge rate is as low as 2% per day, you'd find them with little charge remaining after a couple of months. The high-capacity, fast-self-discharging NiMH cells seem to be a reasonable choice for certain application - those in which you expect to drain 'em within a few days of use, and will need to recharge them regularly in any case. Photo-flash applications, or listen-and-talk applications in a portable radio, or that sort of thing. They're a poor choice for occasional-use or standby applications. If you're using your MFJ-259 for several hours per week, standard 2600 NiMH cells may be a good choice. If you use the analyzer only occasionally, I think you'll be happier with either NiCd, or low-self-discharge 2000/2100 NiMH. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |