Gervais VE2CKN wrote... > my battery of my new does not stay charge at all for a long time, I > have been lucky if it stay 3/4 day on...
09:00... I turned a PX-777 on with a fully-charged stock 1200 mAh battery attached. I have the backlight on all of the time and the radio is scanning. The frequencies I'm scanning aren't too busy, but there is some activity. I've used the radio quite a bit since I got it, sometimes in some lengthy QSOs and I've never ran it down. Let's see how long it lasts today with it on scan. I don't have the programming cable yet (it's on the way) so don't know if "battery save" is enabled, but with the radio scanning, it shouldn't make any difference. 15:00... Six hours and still going. The battery gauge is still showing "full" and the radio has seen a few minutes of transmit time. The rest of the time it has been scanning continuously. 16:00... I intended my "run down" test to be mostly scanning, but I just had a 20 minute QSO with it. The radio was on low power and I was probably transmitting as much as I was receiving during he QSO. That's seven hours so far. 18:45... Radio now showing just two bars on the battery indicator. Transmitted (low power) for 30 seconds and still showing two bars. put it back on scan. The PX-777 has been on for only 9 hrs 45 mins, but with a fair bit of transmit time. I haven't tried measuring what the radio draws, but assuming it's in the 100 mA range, it should go for about 12 hours with no transmit time. 21:00... That's 12 hours, and still going strong with two bars on the battery indicator. 21:45... I then had a 20-25 minute QSO on low power starting at 21:00. When we cleared, it was just dropping down to one bar. I think I would have to say that was exceptional performance. Nearly 12 1/2 hours on scan with the backlight on and about 45+ mins of QSO, and it's still scanning. 21:54... no bars showing and still scanning. I took the battery off for a moment and measured 6.79 volts. If I assume a critical voltage of 3 V per cell, it should still be OK. I assume the radio will turn off at some set voltage. Back on scan after. I then remembered the charging terminals on the back... 6.58 V at 22:04 and still capable of transmitting. 22:05... the radio (still on scan) is beeping every few seconds. I assume this is a low voltage alarm. Yup, the battery gauge is now flashing, at least when it's not scanning, and I measured 6.41 V on the back of the battery. The radio will no longer transmit. 22:13... radio turned itself off and I measured. 0 V on the battery whether I use the charge connectors or the ones on the other side. I hope there's some protection circuitry in the battery rather than the battery actually being zero volts! Discharging much below 3V per cell can kill Li-ion batteries! Message to self... if I ever get a low battery warning again, turn it off! Gervais... I take it you are getting less time out of your battery? I got 13 hours and 13 minutes out of it, continuously on scan with the backlight on and about 45+ mins of QSO (low power) as well. If I'm still awake, I'll be able to see how long it took to charge. 73 es cul - Keith VE7GDH -- "I may be lost, but I know exactly where I am!"
