Citizen CB1 Series Instruction Manual page 25

Notes on the time signal reception
When signal reception is poor
High-tension electrical lines or other structures near your house may block the path to
the signal location. This may cause a poor environment for receiving the time signal.
With reference to pages 19 to 21, search for a better place for reception.
Then, attempt to receive the time signal following the procedure on pages 24 and 25.
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It may be difficult to receive the time signal through windows containing wire mesh.
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