I must be an idiot because I have bought a walkman without the charger! I had no idea how difficult it would be sourcing one that doesn't cost a small fortune. Am I missing something...i'm in the UK ....is there a cheap charger out there or a way of modifying an AA charger that I should know about? Any help would be appreciated. Andrew
You might find some useful information in this thread http://stereo2go.com/forums/threads...mstick-type-battery-in-this-day-and-age.1236/ DoubleCee is still around if you need more details on the charger he uses. I don't think anything special is needed. Any AA NiCad charger should work if you can make the connctions. At least you didn't buy an Aiwa with its unobtainium 2V Lead Acid batteries.
+1 to what @Longman said: all my chargers (and with my son being a DRONE aficionado, I had paid for quite a few!) will charge a gumstick...
Many thanks for the advice. I've got an old AA charger in the garage....I'll give it a go when the walkman arrives.
Wait!!!. Here is the thing you need to know. Fully discharging a gumstick battery before recharging it is the key to maintaining it's full charge/discharge cycle. This is critical if you intend using the battery in an MD Walkman. Less so for any cassette Walkman including the DD9. I have been researching this gumstick charging issue for weeks and I have found the solution. You can get a charger that will charge these batteries like a cheapie Pisen charger on eBay but it won't discharge them prior to charging. It also will not indicate when the battery is fully charged. I have found chargers that claim to work on NiMH batteries and switch the charging LED off to indicate full charge has been reached are not fully charging the gumstick batteries. This us because each battery has its own charge time from 6 to 14 hours depending on the current supplied by the charger and the rating if your battery in Mah. The way to work out the charging time for any charger and battery combination is the formula battery Mah X 1.2 divided by the output of the charger. So for a 1350Mah gumstick and 300ma charger it is 1350 times 1.2 divided by 300 or 5.4 hours. The only problem I found is most chargers seem to stop charging the battery after about an hour. You want one that not only discharges but doesn't giving a false full charge reading and stop charging the battery. It's a manual process with these gumstick batteries. I bought an EBL Universal charger only to find the gumstick battery is 1mm too long to fit into it. Not deterred I got it to fit and it took hours to fully discharge but only 1 hour to recharge. Charging current is 1amp though so I thought problem resolved only to find the battery still gives "Low Batt" when placed in the MD Walkman. I repeated the process and used my Sony 110VAC charger to recharge it for 5.4 hours and hey presto 5 hours play time on the MD. Somebody on this forum apart from CC may know of an exact match for the charger we need but alas I'm finding it's a two step process to fully discharge and 100% recharge the NH-14WM battery. I hope this helps.
Since my Sony WM-501 is running just fine now, thanks to the help on this forum and Marian's excellent belt, I can now look at the gumstick battery solutions. My walkman came with an original Sony NC-5WM battery, a NiCd with 450 mAh capacity, and its original "dumb" charger, a Sony BC-7. I also bought a new Vapex NiMh 1450 mAh battery. The original charger is not recommended for charging NiMh, so I initially thought buying a battery eliminator kit (see below), cutting its USB plug and connecting the wire to the prongs of the BC-7 charger (after removing all the electronics inside). That would allow to charge the gumstick from modern AA charger. But it also means breaking the thermowelded shell of the Sony charger. And then I learned about the meanings of the Li Ion Cell numbers. A 18650 cell would be 18 mm wide and 65 mm long, comparing to the 16 mm and 65 mm of a gumstick, this seems to be a nearly perfect fit. And that you could use one of those smart charger available everywhere. Can you confirm that those chargers would charge a NiMh gumstick? No problem with the voltages, since the gumstick is 1.2V and the Li Ion 3.7V? Generic picture:
I certainly wouldn't put a NiMH battery in a LIPO charger unless it specifically said it would do NiMH as well. As you have noted yourself the voltage is far too high. I don't see an issue with charging NiMH in a NiCad charger. The only thing that you would probably find is that it would take noticeably longer to charge as NiCads are lower capacity so are charged at a lower rate. On the plus side a lower charge rate is kinder on your batteries. I don't own any equipment that uses Gumsticks but it shouldn't be difficult to modify an AA charger. https://www.candlepowerforums.com/v...-charging-NiMH-gumstick-batts-with-AA-charger Something to watch out for is that some low cost chargers will only charge two cells at a time. You don't want one of those. p.s has anyone tried the Ikea USB AA charger https://www.ebay.co.uk/itm/New-IKEA...762148&hash=item594ae2abf0:g:PwMAAOSwYxBemlMN I'm tempted myself. I have a Tronic intelligent charger that has an annoying habit of indicating "Battery Fault" then refusing to charge completely flat batteries.
Thank you for your reply. I watched dozens of videos this afternoon, and from what I understood, those smart chargers will autodetect the chemistry in the batteries and choose the correct voltage accordingly. I think I will give ti a try… and you can use these charger for all kinds of batteries.
This is what you need charger $17 https://www.aliexpress.com/item/328...earchweb0_0,searchweb201602_,searchweb201603_ Gumsticks 2 pieces $9 https://www.aliexpress.com/item/32888098902.html?spm=a2g0s.9042311.0.0.27424c4dB4b9dV I ordered a couple of those gumstick battery's from this seller and they work great!
This topic does the rounds fairly regularly in S2G. I have multiple gumstick batteries and numerous smart and dumb chargers and I have gone back to my original Sony dumb 110VAC charger for all my NiMH charging needs and it works better than the smart chargers which are great for fully discharging a battery before entering the charge cycle but seem to indicate the gumsticks are fully charged after 3 hours. Try telling that to an MD player. No way. The best thing to do is use the formula to calculate the charge time based on charger output rating and NiMH battery capacity. For my Sony dumb charger it's a staggering and slow 12 hours but it seems to work. Even my MD players accept the batteries are not "Low Batt" when you put them into the player after 12 hours. I have only ever found 1 out of 10 of those generic pale green Chinese 1450mah batteries ever charge sufficiently to power up an MD but they work fine to varying degrees in a tape based Walkman. A word of warning for those in other geographies however. Those Sony gumstick chargers supplied up to at least 1996 with expensive cassette Walkman like the EX1 and WX1 are strictly 110VAC only. I ruined one assuming it would be 110-230VAC and they are not!
What worries me, is that you can easily over charge an NiMH when using a NiCd Charger. And you mention another point, charging time. If I want to fully charge the 1450 mAh battery with the Sony BC-7 and its 66 mA charging current, it would take around 30 hours. That's no fun.
Yes that is too long. The risk of over charging is a consideration. NiMH probably safer than Li-ion batteries though which can catch fire without over charging protection either inbuilt or in the charger. I think if you are using the NiMH batteries for a cassette based Walkman it is probably better to use a smart charger. The MZ-R55 MD Walkman is a pain to operate on gumsticks. There is some problem with the charge detection circuitry in those. Unless I charge a good battery on the old Sony charger for at least the 12 hours it won't run the MD. I often get the "Low batt" status on the MD but can take the battery out and put it in the DD9 and it runs it for 3 to 4 hours indicating it had full charge.
So I finally got this smart charger, it seems to work fine with the new NiMH gumsticks. The old NiCD Sony gumstick seems to be definitely dead. Maybe I'll try to build a physical adapter, so that the batteries are secured in place. Right now they wont move on their own though.
I will get one because the sliders alone accommodate a gum stick battery which most of these generic chargers have bays that are too short for a NiMH battery. Thanks for the info.
