• Length: 1.75 in. (44 mm)
• Width: 1.0 in. (25 mm)
• Height: .125 in. (3 mm)
• Weight: .10 oz. (2.8 gms)

The Hobbico VoltWatch is an accurate, inexpensive onboard battery monitor for 4.8 volt receiver batteries. The unit consists of 7 small but brightly color coded LED's that light up one at a time depending on the voltage condition of the receiver battery. The unit is very small measuring and extremely light-weight. Mounting is easy with the supplied double-stick foam tape. The unit is connected by plugging the Futaba J-type connector into any unused channel in the receiver. The connector can be changed for other brands of receivers.

In order to determine just when the different indicator lamps came on, the monitor was set up with a variable D.C. power supply and a Fluke Digital Multi-Meter. The green Max lamp comes on at 5.14 volts or above. This will go out and the next green light will come on when the voltage is reduced to 5.05 volts. The next 2 green lamps in the safe range come on at 4.95 volts and 4.86 volts respectively. Lowering the voltage further makes the 2 yellow Low lamps come on at 4.76 Volts and 4.64 Volts. The last LED is red and comes on when the voltage is reduced to 4.62 volts. That is precision monitoring. The red light will go out if the voltage drops below 3 volts.

The VoltWatch adds less than 10 mA load to the onboard system. There are other onboard battery monitors available but most are 3 to 4 times the price of this little gem. This unit has an excellent price\performance ratio and is perfect for adding under the canopy of planes. Price is very reasonable and it has a 2 yr. Warranty. This is an economical, easy and safe way to monitor receiver batteries.