What is a good source for a 12V battery for externally powering the Ultra-Lap transmitter?
After a bit of searching and testing, we have found a very good and inexpensive battery that is ideal for powering the transmitter. The battery is a sealed lead acid (SLA) 12V battery that can be obtained from www.batterymart.com — the part number is SLA-12V7-F1. We have tested it and it powered the transmitter for 120 consecutive hours before it needed to be recharged. Since it is a sealed battery, it can be stored in any position without worrying about spilling acid. In addition, they sell a charger; it is part number ACC-41A12500. It would be preferable to use a standard 12V automotive type battery charger, but this little charger will do the trick. However, there are two things to be careful about with this charger — since it does not reduce the charging current when the battery becomes fully charged, it should not be connected to the battery for more than about 12-16 hours. Also, when it is plugged in, be careful not to short the leads together.
