Extend run time by swapping 1.8" for 2.5" drive

[LoveLearn]

Hi,
It has been a long time since I've participated in these forums. Those who are long-time participants may recall someone who stacked four 25-pound barbell weights on his ARJR20's elastic bumpers just to see if it was strong enough to sustain that load undamaged, which it was. That was me. I'm also responsible for about half the language I just downloaded as the Archos JukeBox Studio Player Rockbox Manual, although what I submitted was for the recorder. Somehow my language migrated. So those who have damned those manuals, I'm only one of the people toward whom you may want to throw Rocks.

Ok, prudent hard drive selection for use in battery-powered pocketable devices always requires considering trade-offs between power consumption and run time between battery recharges. The fact that carrying over 100 gigs of mp3 files implies that it would take months and months of continual "24/7" playback without any repeated content just to hear everything we can carry in these machines. So for most of us, I argue that extending file storing space has very limited utility so long as we have USB 2 access to our master files which we should all have backed up on some other device. Swapping files isn't that much of a chore. I just moved the first 6 months of my Coast To Coast radio subscription downloads onto one of my Archo units and I didn't need to sit there watching it happen. That was about 9 gigs for those interested. Loosing your only copy of your 50 gig mp3 collection! Tell me that didn't really happen.

Since I'm arguing that more storage space isn't gaining much utility for most Archos portable owners, please consider run time. In the context of Archos recorders/players, most use time intermittently cycles the hard drive on briefly, then lets it rest. If I recall correctly, if all other factors are held constant, rotational momentum varies as does diameter cubed. That's one steep curve.  Constant running time power requirements are almost immaterial to this battery loading function since their run time is so limited. And file reading uses less power than file writing anyway. The main battery-killer demand from intermittent cycling small-package hard drives is startup power demand. In this area, rotational momentum changes linearly with the number of platters. Some are single and some are dual platter drives.

Informing your perspective by that context, consider starting current requirements of Hitachi C4K60 and Toshiba MK8004/4007 1.8" drives.
Find maximum power draw in the comparison table at
http://www.tomshardware.com/2006/04/28/small_is_beautiful/page3.html

As you probably expect, maximum power draw occurs while drives spin up to speed. What that table does not show is total power consumed by each startup event, which is what we should be comparing. If  Hitachi C4K60 1.4 watt maximum power draw is sustained 128% as long as Toshiba MK8004/4007 1.8 watt maximum power draw, they use the same amount of power per startup event. We don't have that information so I don't know which costs less milliamp-hours to bring up to speed. But they both offer huge startup power drain costs compared to 2.5" drives. If you consider 2.5" drive power requirements in the context of Archos mp3 playing, their most important specification is starting current rather than running current. That's very different from laptop use where starting load represents a tiny proportion of total drive power budget.

So why does this have any relevance to Archos units which were sold with 2.5" drives?

Answer:
"Hitachi uses the UltraATA/100 interface and ships CE versions with ZIF connectors, or PC versions that use the Mini-ATA connector. The connector's placement along the length of the drive is intentional, because the length of a 1.8" drive equals the width of 2.5" models: 70 mm or 2.76". This means that any 2.5" drive can be replaced by the C4K60."

That's from the next page of the Tom's Hardware article linked above. Also, conversion adapters are available so those wanting to interface 1.8" drives from other makers can make that swap. Space left by the 2.5" drive leaves plenty of extra space for a 1.8" drive plus adapter.

I haven't heard any feedback from anyone who's swapped in one of these low starting power consumption drives into their 2.5" compartment, but I speculate that with the best AA rechargeables we should be able to obtain run times well over 20 hours. That's an advantage which would affect almost all owners.  I say almost only because I recall someone, (was it Neon John?), who was running an Archos on AC power supply to provide continual playback background music in a restaurant.

Anyway, I hope I've cast a different light on the oft-discussed run-time per charge topic. So if 60 - 80 gigs would be enough space yet you'd like a huge boost to your running time per charge, consider swapping in a currently available 1.8" drive.
John

[tspoon]

 I generally get over 20 hours already with the 8mb mod, which was admittedly rather messy not to mention scary to install. Maybe when 1.8" devices are common I might go there too.
 I have to agree with the 80gb maximum practical limit for music only devices. I put an 80gb drive in my V1 and loaded 70gb of music in february this year. It holds around 12,800 songs, at Lame APS quality or better. I then went on a month long holiday on my bike, listening to music up to 14 hours a day. By the end of that I had listened to about 3500 songs. Since then I listen around 2.5 - 3 hours per week day and am up to about song number 7000, just over halfway really. 80gb is certainly plenty for me.

[krick]

Would it be possible to convert the Jukebox Recorder over to a flash based device using something on this page...

http://www.mini-itx.com/store/?c=16