I'm almost embarrassed to ask this.

If you have a scanner plugged into the wall and you have rechargeable batteries in it (yes they charge in the scanner) and are listening at the same time, are the batteries still charging as you are listening or do they have to charge when the scanner is turned off?
Technically, you aren't using the batteries because it's plugged in to the wall.

What are you worried about? I don't charge them in the radio, my personal preference. They should be fully cycled, go from dead to a full charge before they get put back into use. You'll get a hundred different answers from a hundred people. I have 5 sets of NIMH batteries which cycle through two hand held scanners. NICAD batteries can get a "memory" and NIMH batteries get much less of a "memory," while the new LI-ON batteries have little "memory" to worry about. You can read up on batteries here: http://www.batteryuniversity.com/partone-3.htm

It's not a bad question to ask at all, but depends on the scanner and the
batteries. I have an older scanner (PRO-92) which is plugged into its wall
charger all the time, and the scanner is turned on only some of the time.
Because the charger is unregulated, voltage drops while charging (OFF), and
drops further when the radio is ON and charging the batteries at some rate
(which has not damaged them is the last 6+ years). Granted, this radio
was designed for NiCd batteries which can overcharge indefintely at some
finite rate (although it is not good for them) without overheating and venting.

Radios designed to charge NiMH batteries (the majority these days) may
have a charge shutoff mechanism so probably behave differently.


Dave

The scanner I have is a Uniden BCD396T.

I always say to never charge batteries in the scanner itself. I have heard so many horror stories of batteries 'exploding' while charging, it just makes sence to me to spend $20 or so and get a seperate plug in battery charger. I would much rather ruin a $20 unit then a $400+ unit. But that is just my opinon.

I wondered about this myself. I usually charge/listen at the same time but when I take the charger out for mobile purpose, I let the batteries drain. Then I take the batteries out and charge in external charger (Kodak 1 hour charger). And then repeat the same process.

Scanner: PRO-97
Batteries: 2200 mAh Ni-Mh

JRay1670 said:

If you have a scanner plugged into the wall and you have rechargeable batteries in it (yes they charge in the scanner) and are listening at the same time, are the batteries still charging as you are listening or do they have to charge when the scanner is turned off?
Technically, you aren't using the batteries because it's plugged in to the wall.

Click to expand...

You've gotten some good info on whether to charge in or out of the scanner. Out is probably better, but your question has really yet to be answered.

For your 396, the batteries will charge, though at a slower rate, while the radio is on. Just make sure you have the ALK/NiMH switch set to NiMH.

Any battery is liable to leak, get hot or explode while being charged. One would expect this from new batteries (which have not been run and may have a defect) or older batteries nearing the end of their service life.

I am a bit like Clyde, I have spare batteries and I will charge them outside the scanner. But I am not like him in that on occasion, I will use the wall charger. Usually like when I am travelling or somewhere where I don't have quick access to the spares and need to get the scanner back up and running.

If you ask what is a good charger, you'll probably here the Maha C9000 (I just got one and it is nice). Avoid the 15 minute chargers, as the way they charge does reduce battery life. Nice when one is in a hurry, but a slower overnight charge is really better. The C9000 will even run a discharge and then recharge. Look through the forum for some discussions and links for chargers and batteries.

Dave is absolutely right provided certain precautions are taken. It all boils down to using the recommended batteries for the scanner, make NO substitutions or you can cause severe damage to the charger. In this case bigger isn't better, "stock" chargers internal or external offer no headroom allowing for bigger batteries and may overheat and burn out. Bigger batteries are just fine when an adequate external charger is used.

MOST importantly is NEVER charge lithium or NiMh batteries like you do NiCd cells, each requires a different charger. Breaking this rule can result in damage, fire and even physical harm if you get sprayed by very hot bits of an exploding battery.

One more thing, this business of "cycling" NiCd batteries is pure bunk and it can get you into trouble as follows. As long as you "top them off" immediately or as soon as possible after use they'll be just fine and they can remain on trickle charge indefinitely. You run into trouble when you leave them partially or fully discharged for a long period, they will develop a "memory" at that point and refuse to take charge above it. In other words once they remember that point they can never again be fully charged.

It is for this reason they're sold fully charged so always buy fresh stock. If it's been lying around it will self discharge through it's own internal resistance so if you buy old stock you're buying a battery with a memory as stated above. They can grow cadmium "whiskers" too and short out on the shelf or after a few charging cycles so again always buy new stock and keep them fully charged even if you don't use them for a while.

JRay1670 said:

If you have a scanner plugged into the wall and you have rechargeable batteries in it (yes they charge in the scanner) and are listening at the same time, are the batteries still charging as you are listening or do they have to charge when the scanner is turned off?

Click to expand...

The 396 initiates a 14 hour charging period every time you apply power through the DC jack. It makes no difference if the scanner is on or off.

If you don't completely run the batteries down before connecting the AC adapter, you will quickly ruin them by overcharging them.

You can easily verify that the batteries are being charged by pressing down on the scroll knob; the battery voltage will be displayed in the upper right corner of the display.

All of the advice here is great. As others have stated their own preference is, don't charge them in the scanner. Yes it is only a remote chance that something bad could happen but that chance is there. I would much rather ruin a $20 charger (or up to $50 for a real good one.) than a $500 scanner. Just charge and use them in cycle and bring an extra set with you if you think you are going to need them. I always have an extra set handy.

good stuff here! cruisin' the forum lookin' for good answers! found 'em!
ps buying a charger, seems like the MH-C9000 is a good one for my Uniden BCD396XT? I have Mi-Mh batteries.

It's fine to browse through the forums, but you really shouldn't bump old threads like this back to life for no reason (this thread is over 3 years old!).

CoolCat said:

It's fine to browse through the forums, but you really shouldn't bump old threads like this back to life for no reason (this thread is over 3 years old!).

Click to expand...

CATCH 22. If I ask this question without checking the past threads and posts someone will say, "you should
check past threads and posts before posting a new one." I had a question, what is one to do? That was my reason.

kb2vxa said:

It all boils down to using the recommended batteries for the scanner, make NO substitutions or you can cause severe damage to the charger. In this case bigger isn't better, "stock" chargers internal or external offer no headroom allowing for bigger batteries and may overheat and burn out. Bigger batteries are just fine when an adequate external charger is used.

Click to expand...

Please explain why you believe what you posted. It defies logic.

I can see where changing battery chemistry to one the built-in charger isn't designed for could cause problems, but I don't see how increasing the capacity could damage the charger.

NiMH and NiCd chargers are current limited. A higher mAhr capacity battery just takes longer to fully charge. It doesn't draw any extra currrent or put any extra load on the charger.