Midland GXT650 battery problem.

Like many I guess I just joined here looking for help. I have several Midland GXT 650 FRS/GMRS radios that I have used for a few years & I find I’m beginning to get an odd problem.

A search of the Internet reveals the Midland “BATT-5R” built in rechargable battery can’t operate properly any more on the high power setting. Several sources have said its a battery related problem & my tests seem to confirm this. What happens is that freshly-charged batterys work fine, but as soon as they have a couple of hours use on them the b[/b] setting refuses to work. It won’t transmit either voice, or a call tone. Switching to b[/b] fixes the problem, & so does using only the FRS channels. Recharging the built in battery also “fixes” the problem, but only temporarily.

I tried a set of “AA” rechargables & even partly discharged & showing reduced bars on the battery indicator bar they work fully for all channels, so the question becomes this:

Can I use the existing sit-in charger to recharge either Metal hydride, or hybrid type AA rechargables without damage to the charger or radio?

Has anyone actually done this & how well did it work?

Thanks in advance for any help you can offer.

I think I just answered my own question!:o

The battery pack has additional contacts to work with the sit-in type charger passing through the battery compartment cover, so I don’t think I can charge them in the radio. Anyone know of a clever fix for this?

OK, how about the plug on the side markerd for “mic/chg” Its the lower of the 2 the headset/mike plug into, a 2.5mm Jack I think?
Anyone tried this with some kind of rechargable “AA” in situ?

I would strongly suggest you do not do this. The Midland charger/charging ports were designed specifically for the Midland rechargeable battery packs. The rechargeable AA batteries such as Duracell require those batteries to be charged only in the chargers designed for them.

Charging voltages vary between chargers. Even if you are using the same type of battery such as NiMH, Li-ion, etc. the charging requirements for the Midland battery packs and the typical consumer AA rechargeable battery will be different.

At the very least, the batteries will not charge properly. At the worst, it can be a potentially serious fire hazard. Either way you run the risk of damaging the batteries, the radio, or both.

Here a couple of resources that may help:

Battery Type Differences: NiCd vs. NiMH vs. Li-Ion
TWRS-17 - Batteries For Radios

Point taken on charging differences. I certainly wont & cant use the provided charger anyway!

Any idea what was supposed to be used with the provided charging port? It certainly doesn’t accept the coax type charger plug of the supplied charging adaptor.

It is marked as 9DCV @ 300Ma, so I assume that is correct for use with the internal (5 X “AAA” battery) 6.0v 700MaH battery pack. The AA replacment unit’s charger is marked as 2.8V 360Ma X2 (it uses 2 channels to parallel charge 2X2 “AA” batteries for a set of 4) Why can’t I just make a physical adaptor plug so the batteries get the exact same time volktage/Ma rate but via the charge port?

The charging adapter is intended for use with the desktop charger. According to Midland, you need an LXT charger such as the one included with the LXT118VP to plug into the mic/chg port on the GXT series radios, however it will take the radio twice as long to charge.

This is the Midland Y charger Part number LXADP. It is available as a special order item from Midland. Fortunately we have these at Buy Two Way Radios for $9.99 plus $5.99 shipping. Currently it is a special order item but we do have them in stock and can ship it today. If you want to order one, give us a call at 1-800-584-1445 and our sales staff will be happy to assist you.

There is one important item to consider. Based on your original post the BATT-5R in your radio is weakening. All batteries have a limited life span and as they get older, they no longer hold a sufficient charge to keep the radio from switching from high to low power. The GXT650 is designed to automatically shift from high to low power mode when the battery meter drops to one bar, however as the battery ages, its ability to maintain consistent output in high power mode weakens, so if the battery has three bars it can still drop to low power mode if the battery cannot sustain the power output for TX bursts in high power mode.

Even with the LXADP charger you will still have this problem because the battery is aging. The solution is to either use alkalines instead or replace the BATT-5R.

Thanks for the link.

Yes, I understand the real problem is the older batteries, I was just wondeing if I couldn’t kill two birds with one stone by using “AA” rechargables which are both higher capacity (250 MaH instead of 700MaH) & which I have a bunch of. This would also standardize my battery unventory & give me access to spare sets of them as well.

It looks like its going to be more trouble than it’s worth though.:frowning: