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Battery Information
Battery Details

This battery pack can be remanufactured from your old, dead, pack. See below for details.

Equivalents:

FNB-72, FNB-72(C), FNB-72X, FNB-72XH, FNB-72XX, MHFNB72, MH-FNB-72, FNB-85, OPP-817+, WH-FNB72, WWN-FNB72,

Image not to scale.	Common Name.	Dimensions. Height × Width × Length.	Chemical Composition.	Nominal Voltage.
	FNB-72.	62 mm × 16 mm × 102 mm (approx) Contacts: Polorisied plug.	Ni-Cd, Ni-MH.	9.6 volts.

This battery is really easy to remanufacture from an old, dead, pack. It is just 8 × AA rechargeables (Ni-Cd originally but Ni-MH are fine) in series with a thermal fuse and plug lead fitted for connection. Just a word of warning: Make sure you use a thermal fuse! Batteries can explode if they get too hot, not a good idea inside an expensive radio.

If you use the largest capacity you can find you could end up with a battery that lasts nearly 3 times as long as the original. There is a thermal fuse inside the old pack, carefully cut away the outer heat shrunk sleeving to check and reuse if possible. If not source one from somewhere!

If making the battery from scratch make sure that you find a thermal fuse (auto resetting type is best), and fit it between the center two rows of cells as shown in the red box below:

The FT-817 rechargeable pack has 4 wires running to it from the connector:

• The two red wires from the connector go to the battery positive.
• The two black ones go to the battery negative.
• There is a fifth wire, that is used to detect a non rechargable pack ( the "AA tray").

The connector is wired as follows:
With the connector facing you, looking into it (leads facing away from you) and the two small polarising bumps LOWERMOST.

NC, RED, RED, BLACK, BLACK. (NC = No Connection)

Once the pack is made up use some good quality electricians tape to wrap around and cover all the inter cell connections. Do this well, you do not want a short circuit!