I am building an extremely simple circuit to connect a load with a very small consumption (maybe 10mA constant with say 100mA for 1 second twice a day at 9 volts DC) to a rectified plug pack which supplies rectified 8.9 volts DC and I want to include a battery backup in case of power outage. I was hoping to just use an alkaline 9V battery as any power outages would only last for say 1 hour absolute maximum and be very infrequent rather than add components to the circuit and use a rechargeable battery. The battery is only present in case of a power outage.
Using schottke diodes I have measured a possible 0.7 volts being constantly present at the 9 volt alkaline battery. Alkaline batteries should not be charged but would 0.7 volts be a problem? Would a resistor in series to the battery help?