This a brief description of how I replaced a dead battery in an AMB MX transponder. According to documents I've read from AMB, replacing of batteries is NOT supported by them so I have to put a DISCLAIMER: This is NOT a description in how to replace a dead battery in an AMB MX transponder, this is only a documentation about how I replaced the dead batteries in my own transponders, entirely at my own risk. I take no responsibility if you break any transponder, catch a cold, lose your saving or are befallen by any other misfortune following my instructions. I've got eight dead transponders and did this operation on five of them. All of them work today. I'm not a native english speaker/writer and used Google translate to get some English words I didn't know. In other words: language errors might exist. The photos were shot with a cellular phone in a dark garage. The quality is quite poor. Sorry for that. Things needed: A hacksaw blade, one knife. A NiMH replacement battery type "AA" made for soldering and soldering tools. A vise is recommended. The original battery in my transponders had the capacity of 1250mAh, but I only found one with the capacity of 2100mAh whithin a convenient radius. I don't have a clue what the white plastic inside the transponder is made of but I suppose it's unhealthy. Therefore I don't recommend grinding down the surface to reach the battery.
	I used a blade from a hacksaw to loosen the black bottom from the orange housing, use the blade all around the transponder until you see the black plastic.
	A nice try to show the result of the using of the hacksaw blade in the picture above.
	Use a knife to separate the black bottom from the orange housing, move your hand in the right-left direction and please try to not cut yourself. When the black part is loosened all around you can carefully use a vise or pliers to apply more force to remove it completely.
	An illustration of me removing the black bottom. Notice the thin pin at the right in the bottom part. It seems important that this pin is intact for the tranponder to work.
	Use the hacksaw blade to cut the orange housing like this. I suppose a sharp knife instead of a hacksaw blade would make the reassembly a bit easier but I simply didn't have any ultra-sharp knife available. I only cut the long side, about 10mm on the top and the intersecting cut on the top. Don't cut across the transponder number label, it just looks like I did it because the plastic got mis-coloured when i folded it before taking the picture. The goal here is to open the tranponder up without damage the charging/operating LED.
	An illustration of how the battery is mounted. You can use a knife to cut all the white plastic away but I used the hacksaw blade to cut just a few millimeters deep and used a knife to crack the white plastic. Much faster and less risk to cut myself in the back with the knife. The next picture is just an illustration of where i used the blade. Pros: speed, exactness, less risk of cutting yourself. Cons: the plastic cover around the battery will follow the white plastic and make it harder to read the text on the battery. Possibly risk in damage the tranponder but all of mine work fine.
	An illustration of where to carefully put the slices used to crack the plastic away. I used the hacksaw blade to cut just a few millimeters deep. Do not go so deep that you reach the battery! 1: Use the knife to remove the white plastic and make the foam visible. 2: Make the cut about 10mm from the bottom of the transponder to reach the other pole of the battery. Crack here before cracking the long line.
	After the crackwork is done.
	Cut the electric connectors as close to the battery pole as possible, leaving as much metal left as possible for soldering the replacement battery.
	Just a photo. Self explaining? Make sure you leave as much from the connectors as possible
	Notice the electrical connectors and the "+" sign in the battery cover that is left in the white plastic at the foam side. It's wise to use a CD marker pen and write + and - somewhere at the transponder. It's quickly forgotten. On all of my transponders the "+" side is the side with the foam.
	I added this photo because it shows the location of the battery very well.
	I know. I should have shot some photos showing soldering the replacement battery and the retro fit of the housing but I was so filthy so I didn't want to lay my hands on the cellphone. I will do that when I fix the three remaining transponders. However, if you showed interest in this "guide" you're probably skilled in soldering. I used silicone sealer to fill upp the space that the white plastic once occupied and used masking tape on the orange housing to keep the transponder from looking to messy afterwards. I clamped the tranponder in my vise for 24 hours and it looks quite ok after I removed the masking tape. The original battery appeared to be a "GP", with the capacity of 1250mAh, my replacement battery had a 2100mAh capacity I'm not well educated in electronics and I suppose skilled people will complain in my choice of replacement battery and methods to disassemble the transponder. As I wrote earlier: I'm not responsible, if you follow this documentation and break something or hurt yourself. It's only a documentation of how I did it. 2011-04-23 Martin Burman