These people may be able to offer advice about your transponder (or transponda)

http://abacuscaralarms.co.uk/alarmshop/index.php?act=viewProd&productId=117

Theres some more info in the later posts here:

http://www.pocuk.com/forums/viewtopic.php?t=104859&sid=d5f8569742e99cfd21c707d9aeb7a25f

Anon
February 2016