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Question about the Panasonic 470 - Page 4

post #46 of 73
It's the diff between the SL-CT470 and the SL-CT470A. Two different models, two different sounds, two different colors, two different prices....

oh, and that Zeroshipping stuff?

We are sorry to inform you that the item PANASONIC
SLCT470 is not available. Thank you for you interest
to our items.

Please visit our site @ zeroshipping.net

Have a nice day.
post #47 of 73
*coughs* now what?
post #48 of 73
Shamelesssss BUMMMMMMPPPPPP!!!!!!!
post #49 of 73
I did a google search, and all the prices hovered around 75 to 90+. For the stores you listed, only Let's Go Digital was listed at Reseller Rating, with a score of 1.7.

If you found a good source with a good price, you could become a Head-Fi hero.
post #50 of 73

Rechargeable battery-life update!

I did further tests on battery life, using two headphone/earphone models that I know to have roughly equal voltage-sensitivities but very different impedances (the 16-ohm Sony MDR-EX70LP and the 120-ohm Sennheiser HD 590) with the anti-skip turned off, and a third test with the Senns and the anti-skip turned on.

The SL-CT470's owners manual claims a 6-hour battery life with the anti-shock turned off, and an 8-hour life with the anti-shock on.

Here are my test results:

Low impedance, anti-shock off: 7.9 hours
High impedance, anti-shock off: 8.1 hours
High impedance, anti-shock on: 10.3 hours

The tests were conducted with the volume set at 8/10, the EQ defeated and the play mode set to "repeat whole disc" mode.

Note that the battery life generally exceeded Panasonic's claim by an average of 2 hours - and that's with the supplied NiMH AAA rechargeable batteries bundled with the PCDP. And as I said, the batteries charge in 1.5 hours - half as long as Panasonic's recharge-time claim.
post #51 of 73

This is perhaps off-topic here.
IMO the bult-in chargers on most CD/MDP are bad. They charge at high current C/3 to C without any sophisticated overcharge protection that such a fast charger MUST have. Thus the batteries are most probably overcharged, which at these high currents shortens their live severely.
I'll give you an example
My Sharp MDs internal battery (gumstick) is rated at 1.2V/1250 mAh. The charger pumps it up for 3,5 hours at 2V/800 mA!!! No wonder than the battery has already lost some capacity after approx. 50-60 cycles. The manufacturers don't care. They want to ensure full charge at shortest possible times (although some capacity is lost at very fast charge rates). When the bat. goes bad, well at $25 per gumstick they don't mind if you buy a new one every now and then.
The moral of the story is that if you want to prolong the live of your batteries take them out and recharge them in a proper charger.
Sorry once again if this is far off topic.
post #52 of 73
blr, do tell more. Here I am thinking that being able to charge a battery in 1.5 hours for my Sony E900 was the greatest thing since the discman. I had no idea that it killed the battery faster. Thankfully the E900 runs forever on one charge of its NIMH battery...ever since buying it about a year ago, I've only recharged it about 5 times. But what if I completely drain the battery through usage, to the point where the player just can't turn on? Is it still better for it to go through a discharge cycle (which I assume the charger wouldn't have).

So, I guess no place sells a NIMH gumstick recharger that does discharge? Given Radio Shack is so great at making everything into generics eventually (such as the bonded AA NIMHs that Sony's old discmans used), they should consider making one...
post #53 of 73
I guess I've been lucky. I have a Sony discman with a 1200mah Nimh battery pack that charges in about 3 hours. I'm using a battery thats older than my discman. I used the one I bought for about 1 year and a half with no problems but then I lost it and a friend of mine had the same battery in a Sony D-181 he'd gotten the battery when he got the discman which was almost 4 years ago now and I think about 1 year ago he lost his discman but not the battery so I got the battery and it's now gone through 4 years of constant use. It originally got about 9 hours from a charge and right now it seems to get about 5 or 6.

Now I want to start using my newer 1600mah GP batteries but they're rated for a longer charge time and I'm worried my discman will wreck them overtime from overcharging them. I can't afford a charger right now so I'm just waitin and using my old battery.
post #54 of 73
The thing with most NiCD and NiMH batteries is that they can take a fair amount of overcharging at low currents, say C/10 or below (C being the battery capacity in mAh). This means that if you battery is say 1300mAh charging at 130mA or below doesn't hide a risk of dangerous overrcharging. In fact some manufacturers, like GP for instance state that their NiMH cells can be charged indefinately at C/10 or below. I don't really believe this is the best thing one can do, but leaving it in the charger for several hours longer won't hurt them badly.
The things change when you apply higher currents. The temperature and pressure in the cell rise significantly at overcharging (try to touch your walkman at the end of the charging). If the current is high enough, the H2 and O2 formed at the electrodes cannot be recombined, the pressure rises and finally the cell vents (explodes).
Don't worry, this will not happen to your MD. Sony has limited the amount of overcharge. However, charging at this rate still heats the battery and the pressure rises every time you do it. This shortens the live of your battery.
Typically, the live expectance of the modern NiMH batteries providing proper charging and care is applied is anywhere between 500-800 cycles before the capacity drops significantly. This means that with proper charging they most probably will outlive the portable. With the abuse of the fast in-unit charging these batteries last for for no more than 100-150 cycles, go figure. You can fast charge NiMH batteries without a risk, but you'll need a more sophisticated charger that can terminate the charging at the exact point. There are several methods to do this, we can perhaps discuss this in a separate post.
About the full discharge, NiMH have much less memory effect than NiCd, which means that it is not necessary to discharge a NiMH cell every time before charging it. Once every 5 cycles is usually enough.
However, be careful there too. I don't know how Sony designed their charger circuit. If it has only time cut-off (timer), charging not fully discharged battery will mean even more overcharging.
Hope this helps.
post #55 of 73
In my experience, batteries charged in "overnight" chargers never came close to fully charging any of the batteries that I've used. In fact, a recent set of 1600mAH NiMH AA batteries charged in such an "overnight" charger (one that requires at least 24 hours of charging) never gave more than 3 hours of running time/"battery life" (on my Sony D-EJ721 PCDP, which is supposed to run about 26 hours on such NiMH batteries) between charges. (Okay, maybe those brand-new "3-hour" 1600mAH NiMH batteries that I used were duds - and I borrowed, not bought, an "overnight" charger that claims to charge NiMH batteries.)

Unfortunately, none of the recharger/conditioners that are readily available (at most stores) have an "overnight" charger; all of the charger/conditioners that I know discharge batteries all right, but then shoot themselves in the foot by including "fast" chargers that deliver more than C/10 of charging current.
post #56 of 73
In fact, there is nothing wrong with fast charging. Both NiCd and NiMH cells are quite happy with 1C currents. However, any Overcharging at these currents can damage or at least severely limit the lifetime of the cell.
My stationary (home) charger pumps up two 1800 mAh AA cells for less than 2 hours and at the end they're just slightly warm. That's because there is no overcharging. My MDs gumstick is heated to at least 45-50degC when abused by the charging system of the portable.
post #57 of 73

What about my question?

Where should I buy the SL-CT470 from??
post #58 of 73
Gluegun: You klutz.....all you do is bump, lately - and get some damn cold medicine and stop this coughing....................
post #59 of 73
*takes some halls*

*hacks up a hairball*

anyways, All I want is some advice, that's all.....

and, like, got a better idea for how to get some? Or where to buy this ******** cd player?
post #60 of 73
Just get the 30 dollar "flaming pcdp" made by classic from circuit city......i'm getting that for my birthday - i figure it'll have a decent line-out, and.......that's all i care about.......go MD?

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