Hi. The RioS50 mp3 player was on the market some ten years ago. The owner's manual and reviews are easily found online. I got one at a yard sale for n ot much money a few years back. It lacked the charger and the cable that al lows one to download songs from a computer. "That's why it's so cheap," the seller said.
Almost incredibly, I found the cable at a thrift store. iTunes recognizes t he device, and it works with Rio's software as well. Storage is limited, bu t it has an FM radio. It still works, and I still use it.
It was designed to run off a 1600 mAh NiMH cell. It can run off an alkaline cell or a NiCd cell too. Because I do not have the charger, I have to remo ve any rechargeable cell for recharging. Although the owner's manual and re views are online, I have not found the details for the recharger. What was its output voltage? How much current did it supply? What was the size of th e barrel connector? What was the polarity of the tip and the ring?
If anyone can come up with that information, I would be grateful. The charg er probably worked with other Rio players that ran off a single 1.25 volt o r 1.50 volt cell.
The owner's manual says to charge the battery for at least 5 hours the first time. The supplied battery is (1.6 * 1.2) or 1.9 watt-hours nominal. If the five hours was a full charge, this implies that the charger supplies at least 0.38 watt.
Go to Radio Shack and try their selection of Adaptaplugs until you find the one that fits. If you don't mind spending what they charge for adapters, buy a multi-output adapter and the Adaptaplug; otherwise tell them you already have the adapter and buy just the Adaptaplug (which is still a ripoff at $7). If you can solder, and the Adaptaplug happens to be one of the sizes they carry in a "regular" plug (in the drawers full of small parts), buy the "regular" plug instead; it's cheaper. If you can solder and it's a weird size, just solder to the Adaptaplug pins later. If you can't solder and it's a weird size, buy their 273-350 cable for $5, to turn the Adaptaplug ends into wires.
Go home and plug the plug into the MP3 player. Use a multimeter to measure the resistance between the negative battery contact and each pin of the DC plug in turn. One pin will probably show a low, constant resistance (less than 1 ohm.) This is the "negative" pin.
Now you need a somewhat discharged NiMH cell, some fresh alkaline cells (AA size is fine, C or D will also work), tape (clear office type is fine, but anything will work), and wire. Put the NiMH cell in the MP3 player. Tape a wire to the - side of one alkaline cell, and connect that wire to the "negative" pin of the DC power plug. Connect another wire to the "positive" pin of the DC power plug, and then touch it to the + side of the alkaline cell. If the "charge" indicator on the MP3 player comes on and stays on, then you need a 1.5 V adapter.
If the "charge" indicator doesn't stay on, then use more tape and wire to put a second alkaline cell in series with the first one, - to + . Touch the wire from the DC power plug to the + side of the second alkaline cell; if the "charge" indicator comes on and stays on, then you need a 3 V adapter.
If you can't get any response by the time you get to 6 V (4 alkaline cells in series), don't go up any further.
If you find a voltage that works, use the multimeter to measure the current the MP3 player is drawing when charging the battery, and select an adapter with a little more (not a lot more) current than that. Or, divide 0.38 by the voltage you found to get an estimate - if you found that 3 V worked, 0.38 W / 0.38 V = 0.13 A. Select an adapter with at least the measured or estimated current, up to maybe twice the measured or estimated current. A thrift store can be a good place to find an adapter, if you don't mind shopping around a little.
Cut off the existing plug on the adapter (unless it happens to match) and use the multimeter to figure out its polarity. Wire the adapter to your new plug and enjoy.
Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.
Also, please be sure to wear appropriate personal protective equipment while doing all this. You probably don't need arc flash protection at this power level, but you do need gloves, safety goggles, hand rails, and if your workspace is near the stairs, a properly-tethered fall harness. Someone with first aid training needs to be nearby, and it helps if there is an AED available. :)
On Saturday, November 16, 2013 2:05:48 AM UTC-5, snipped-for-privacy@att.net wrote: > B eloved Leader wrote: > What was its output vo ltage?
Probably more than 1.2 V. More below. [snip a whole bunch of good advice} If the "charge" indicator on the MP3 player comes on and stays on, then you need a 1.5 V adapter. [more snippage] A thrift store can be a good place to find an adapter, if you don't mind sh opping around a little. [snip even more] You probably don't need arc flash protection at this power level,... [snip again] :) Matt Roberds
I've seen some arc flash videos, and they are quite dramatic. I think I can avoid that fate by being careful.
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I have several shoe boxes full of wall warts. It was a thrift store that ca me up with the computer cable with the odd Rio plug on one end. There are t wo thrift stores nearby with bins full of cheap, as in $1 or $2, wall warts . At yard sales, they usually fetch less than that. Finding one with the ri ght current and the right voltage and the right polarity and the right size connector is the trick.
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