Viper24 Posted June 14, 2009 Report Share Posted June 14, 2009 Just bought a pair of Uniden UH065SX handhelds and was wondering if anyone knows if you're supposed to leave them in the charge cradle when not in use. I assumed you could as they've got the same rechargeable NiMH batteries as my cordless phones which are always on charge. The only difference is the radios seem a little warm after several days on the charger which doesn't seem right if they're only getting a trickle charge. My cordless phone batteries never get warm unless they're getting a bulk charge. Anyone with experience or knowledge of these chargers/batteries? Link to comment Share on other sites More sharing options...
Jock Posted June 14, 2009 Report Share Posted June 14, 2009 30 years old Cordless tools, has taught me, charge and use until flat, then recharge. Don't top up charging. Link to comment Share on other sites More sharing options...
len Posted June 14, 2009 Report Share Posted June 14, 2009 Why don't you ring or email Uniden and ask them; they should be able to tell you whats best for their batteries with their chargers Link to comment Share on other sites More sharing options...
Viper24 Posted June 14, 2009 Author Report Share Posted June 14, 2009 As usual, when all else fails, read the instructions but there's nothing in the manual about it. The chances of calling them and actually getting someone that knows is fairly remote so I emailed them last week hoping it might get passed on to someone technically minded - still waiting. I know the batteries can handle it because as I said, they're exactly the same as the ones in my phones which are also Unidens. It's wether or not the charger is designed for it. As far as not topping up the charge, from a practical point of view, if you use the radios one day and return with half charge do you not put them back on the charger knowing you'll be using them the next day? I do simply because it's not practical to totally drain the batteries. Link to comment Share on other sites More sharing options...
Fireman_DJ Posted June 14, 2009 Report Share Posted June 14, 2009 NiMH shouldn't really be left on the charger! While they don't get the memory effect of other NiCad's they can be overcharged. Them warming up means that are being charged rapidly. I doupt the charger is trickle charging them if they are warmed up after a few days. I'd use them, charge them and then take them off the charger. Link to comment Share on other sites More sharing options...
Viper24 Posted June 14, 2009 Author Report Share Posted June 14, 2009 Yeah, I think you're right. It makes sense that the chargers are designed for fast charging unlike cordless phones chargers. Link to comment Share on other sites More sharing options...
Gibs Posted June 14, 2009 Report Share Posted June 14, 2009 Ok, Batteries. As most would know these days Nicads are a waste of money, Metal Hydrides are they way to go. As mentioned before no memory effect (phantom charge) BUT as has been stated, one can over charge them. This is true for all batteries be it wet cell, gel or dry chem. The charger than one needs to keep batteries in peak condition ON a charger is a Switchmode PWD type FLOAT charger {Pules Width Discharge}. Now sadly since these cost a bit more than a standard rapid charge charger, these are generaly not sold with the device. Any good Switchmode PWD Rapid+Float Charger of the correct Volt rating will do the job. Current is not an issue since it will auto change to float charge - read usualy low. However if you just use a standard trickle charger as the main charger it will take quite a bit of time to fully charge your battery, plus over extended periods a trickle charger will harm batteries anyway. So the ideal solutiuon is a 2 in 1 Charger as I mentioned first off. Rapid charge till fully charged with an atuo circuit that kicks in at full charge and switches to Float. Now heres the tricky bit, getting one that enables your battery to be pluged in/mounted/conected at the right volt rating. Myself I tend to rewire the new after market charger directly into the battery mount old original chargers unit. Remove the guts of the old original an throw it away. Good places to look for these chargers is Jaycar, Altonics, Dícksmiths (maybe), your local Ships Chandler (used on Boat deep cycle gel cells) or even a 4x4 outfitter. The problem is getting one matched to the voltage of your radio battery Voltage. Most are an odd voltage like say 7.2V instead of say 6V, 12V or 48V. Another place may be a hobby shop since a lot of the Electric RC models use 7.2V systems. If you could tell me the Volt rating of your batteries, that be a big help. Link to comment Share on other sites More sharing options...
Viper24 Posted June 14, 2009 Author Report Share Posted June 14, 2009 The batteries are 1.2v AA (3 in each radio, 6 total) and the charger which does 1 or both units puts out 9v at 500mA. 6 batteries at 1.2v each makes 7.2v doesn't it? It's all elec-trickery to me. Link to comment Share on other sites More sharing options...
Gibs Posted June 15, 2009 Report Share Posted June 15, 2009 (edited) Hmm, ok, I take it that each battery can be removed indivdualy from the hand sets, they are not a true battery pack ? If so any after market AA Switchmode PWD Rapid+Float Charger is what your after. The reason being is this will allow for you to buy some extra batteries and have those sitting in the charger being maintained ready to use and be simply swaped over as you use them. The original Charger I take it has a 2.5mm or 3.5mm plug that goes right into the handhelds them selves ? If so its mainly a rapid charger only for quick turn around time. If it takes the batteries individualy then its a poorly design type and needs to be replaced with the type I mentioned. The batteries should never get hot in a correctly designed Switchmode PWD Rapid+Float charger, a tad warm maybe on rapid charge but thats it. See heres why I know its of poor design, Normaly AA batteries Dry Cell are rated at 1.5V. 6 x 1.5V is 9V. BUT Rechargeable AA's are rated at 1.2V (alway's have been). 6 x 1.2V is 7.2V. Umm whats wrong with this picture. You have a 9V charger that I bet 10-1 is NOT of a Switchmode design of any type. Its more than likely a Linear type which is just plain wrong for long time maintanince of rechargeable batteries. Now just to confuse you a tad, when charging a battery, the Voltage does need to be higher coming from the charger then what the battery is rated at, BUT not by so much as what yours is. Ok take any standard car, it has a 12V battery, but the Altenator is rated at 13.8V - so it can charge the battery. Now given that a car battery is a wet cell an not a chem cell, it needs that amount over the 12V mark to charge the battery. On a Chem cell 1V over is enough. So it should be 8.2V. Anyway as I said any good after market AA Switchmode Rapid+float charger is what you need to maintain your batteries for a long shelf life. Again places to look for a good charger will be your Electronic stores or even a Hobby shop. Edited June 15, 2009 by Gibs Link to comment Share on other sites More sharing options...
Viper24 Posted June 15, 2009 Author Report Share Posted June 15, 2009 Gibs, the charger is a desktop cradle with 2 docks (1 for each radio) similar to a cordless phone cradle. The batteries are individual and can be replaced by normal AA's. The wall plug is labelled "switching power supply". I'm still not sure because of the similarity to the cordless phone setup and the design of the dock looks to be intended for permanent storage and charging. Link to comment Share on other sites More sharing options...
Gibs Posted June 15, 2009 Report Share Posted June 15, 2009 (edited) Viper I know the type, Its a rapid turn around charger only. Do your self a favour, get an After Market AA Switchmode Rapid+float charger that will do a far better job of maintaining your batteries. Its the sort that takes the AA's individualy ok. Use the original if you need to do a quick recharge but dont let the handhelds sit in the charger for long periods (storage). As I said with the after market type you can keep spare batteries on float until you need them an then swap over, better in the long run. Hot battery = Bad ! ok Id get something like an Ansmann 2in1 Charger and Testing Station. Does all you need plus more, should be about $150.00AU (now you know why they dont include good chargers with devices!) Edited June 15, 2009 by Gibs Link to comment Share on other sites More sharing options...
Viper24 Posted June 15, 2009 Author Report Share Posted June 15, 2009 Cheers mate, you're a wealth of information. I wonder how many of these things get returned under warranty due to overcharging. Link to comment Share on other sites More sharing options...
Fireman_DJ Posted June 15, 2009 Report Share Posted June 15, 2009 Btw, what they mean by "switching power supply" that the voltage is controlled by electronics. They are smaller, cheaper and less likely to break under heavy load unlike the old system. The old system uses electrical coils to adjust the voltage. Big, heavy and cost way too much. I have two power supplys, both 12v. Ones 5amp regulated and the other is 4amp switched. In power output, these are pretty close to being the same. But the switched supply is about 1/10th the weight and less then 1/8th the size. To see them side by side the difference is huge and you can't belive that they give almost the same power. Not to be confused with a switch mode as Gibs was talking about, which starts on rapid charge before switching to trickle charge. Link to comment Share on other sites More sharing options...
Viper24 Posted June 15, 2009 Author Report Share Posted June 15, 2009 Thanks for the info. To think, when I first posed the question I thought it was a stupid thing to ask. I hope Deaddog isn't reading this! Link to comment Share on other sites More sharing options...
Gibs Posted June 15, 2009 Report Share Posted June 15, 2009 NP's Viper. heres a link so as you know what to look for. ANSMANN 2in1 Battery Charging and Testing Station Link to comment Share on other sites More sharing options...
vinneyk Posted June 15, 2009 Report Share Posted June 15, 2009 I had a problem with a radio once but I did something really strange; I range the company that made the radio and bugger me they knew how to fix the problem ; who would have thought that would have happened Link to comment Share on other sites More sharing options...
Viper24 Posted June 15, 2009 Author Report Share Posted June 15, 2009 Yeah, who'd have thunk it? I'm still waiting for a reply after a week. Link to comment Share on other sites More sharing options...
Viper24 Posted June 16, 2009 Author Report Share Posted June 16, 2009 Hey Vinneyk, finally got my reply from the company. "Leaving NiMH batteries in the charger will not harm the batteries but it isn't recommended" Figure that one out. Link to comment Share on other sites More sharing options...
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