Hi folks, I am new to this forum, but it was helpfull for me when I was in Japan. I knew MD, but I was never really interested, until I saw that cool MZ-RH10 in a shop in Tokyo/Akihabara. www.minidisc.org helped me with the decision: to buy or not to buy. You know the result ... Anyway, I am a little bit disappointed about the battery life time. In the manual you can read something about 14 hours, mine is far away from that. So I did some measurements. The results may be interesting for the public. I have measured the current drawn from the power supplies while playing a loud song coded as Hi-LP (Attrc3plus 64kb/s). internal battery only: stand by (quick mode "on"): 0.640mA disc access: up to 600mA play, dark display: 100-120mA (full vol), 75mA (vol=0) play, full display: 170mA play, display half brightness: 90mA record Hi-SP: several 100mA internal battery, external 1.5V: stand by (quick mode "on"): 0 .. -2mA (depends on external voltage) disc access: max 1mA, up to 400mA play, full display: -0.9mA, 120mA play, display half brightness: -1.1mA, 70mA So how can they say it works for 14 hours? Easy: no disc access, no display, avarage volume. This way you end up with 100mA current. 1400mAh / 100mA = 14h. That's in no way realistic. Quick mode "on" means your battery will be empty after approx. 1400mAh/0.64mA = 2187h = 91 days. Please take these numbers as a raw estimate. It's difficult to measure since the voltage drop across the amp meter prevents the RH10 from switching on so it needs external support for activation. Conclusion: "quick mode" may actually save energy if you switch on/off the device often, as it skips the expensive disc search step (up to 600mA!). The OLED appears not to be a problem, its power consumption is moderate. If you have an external battery (1.5V!) applied, a constant current is drawn from it (up to 2mA) to charge the internal battery. As long as the external voltage is higher than the internal voltage, the internal battery is not used.
