Sangean MMR-77 (V1) - Manual (Page 4)

3. Dynamo power
Note:
You can charge the radio via Dynamo power either the battery
switch in battery or dynamo position. The Dynamo charging
is to the built-in dynamo battery not the battery in the battery
compartment.
a. take out Dynamo power handle from it rest position.
b. rotary the Dynamo handle around 120 circles per
minute speed, either clock or anti-clock wise until
the charging LED indicator is on indicating charging
condition.
c. Under normal listening condition, one minute charging
can listen to the radio for around 30 minutes.
(AM band and using speaker).
d. Make sure the handle in its rest position after charging
completed.
e. You can dynamo charge the radio either radio in its on
or off position.
f. Make sure the telescopic antenna to be in rest position
before rotary the dynamo handle.
Note:
When plugged in AC power adaptor into DC jack, the dynamo
charging won’t be effective.
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