A fabricated battery pack consists of 3 boards is used.  One board has 5 ea 12volt batteries (A23) in series for 60 volts. Another board has 2 ea 12 volt (A23)batteries in series with a 1.4 (AAA) battery  for 25 1/2 volts and the 3rd board has 4 (AA) in series for 4.5 volts.  4.5 volts used for audio.   60 and 25 volt used for frequency control on transmitter and are necessary for the oscillator to lock on frequency. The single AAA battery in series with the  2 ea A23 batteries may not really be needed but I did it anyway on the first pack.
Battery holders for the A23 battery can be found on ePay or Amazon.Use a glue gun to secure the holders on 1/8 inch plywood.
When the set is being stored just remove 1 battery from each of the series packs.
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