How long does a transponder battery last?

[ThunderCycle]

I need a transponder and I've seen a few used ones on eBay and this board. Some are 3-5years old and still asking for $320-350. A new factory transponder runs $448. Is the cost savings worth the $100? Or is a
5 year old transponder on its final leg?
Anyone every taken a transponder apart? I see a few dead ones for sale. I have access to some pretty talented electrical engineers who might be able to replace the battery. Anyone ever tried fixing a broken one?

Thanks for the advice,

Mike

[mmarsden]

I bought one from someone. On another forum. And it cost me less than $100. I sent it to transponder services in Australia and for $100. He replaced battery. Tough to replace. Yourself as they are encapsulated in resin that needs to be heated to remove battery..

[Gecko]

I've read that AMB says the average life is about 5-6 years. YMMV depending on the use of any particular transponder. For replacement of the battery, Transponder Services out of Australia is the way to go: Transponder Services While I've not had any work done by him (yet), other garage-mates of mine have and I wouldn't hesitate to use him. He does what he says with no issues (that I've heard of thus far).

[Slowpoke387]

any idea on turnaround time? I have a dead one too. Bought it used last yr.

[mmarsden]

Three weeks.. USPS. Priority. Cost 100. Include shipping both ways