11-07-2013, 10:40 PM
Well by my calculations your radio should draw about 0.25A from the 1.5V battery circuit. A single alkaline D cell should provide about 8 Ah. Thats about 32 hours of play time.
The B supply draw should be around 10 mA at moderate volume. A set of 9V alkaline batteries should provide about 500 mAh. Thats about 50 hours. These numbers are approximate of course. Its hard to tell how the radio will work as the batteries approach the end of their lives.
But it does show that there is really no need to build a 4 cell A battery pack.
My farm radio is still going strong after about 2 months of listening several times a week for 30-60 minutes.
Good luck with it.
The B supply draw should be around 10 mA at moderate volume. A set of 9V alkaline batteries should provide about 500 mAh. Thats about 50 hours. These numbers are approximate of course. Its hard to tell how the radio will work as the batteries approach the end of their lives.
But it does show that there is really no need to build a 4 cell A battery pack.
My farm radio is still going strong after about 2 months of listening several times a week for 30-60 minutes.
Good luck with it.