JJY - Radio-Controlled Clock FAQ

• First check that the clock is otherwise functioning normally.
• If the clock works when setting the time manually, place it near a window facing the direction of the transmission station (Fukushima prefecture in eastern Japan, Saga prefecture in western Japan). Then start the signal reception process and wait for at least 20 minutes.
• The orientation of the clock may also affect reception. Please orient the clock as described in the instruciton manual.
• Radio waves are weak inside of buildings made out of reinforced concrete. Also avoid locations near metal objects, such as window blinds, which can weaken the signal even close to a window.
• If you still have no reception, check the transmission status of the standard radio signal. If there is no service, it will not be possible to receive a signal.
• If you get no signal when manually triggering a reception attempt, then let the clock operate normally for two to three days. If the signal is succesfully received at least once, then the time should be correct to one second. This should be enough to use the radio-controlled clock.
• If there is no reception at all, place the clock outside for at least one day. If the reception is good there, then it is the environment indoors that makes reception difficult. Please check "How can I check the reception environment?" below to help find a location where the clock can operate anyway.
• Depending on the model of the radio-controlled clock, there may be a symbol that shows a succesful reception of the standard radio signal. But this signal may disappear again after one or more reception attempts failed. Please refer to the instruction manual to check the details. To check if the time has been set correctly, please use NTT's 117 service or a similar method.

• Check that the battery is still good. Even if it still provides enough power for the clock functions, it may no longer be possible to receive the standard radio signal.
• If the battery has exceeded the battery life specified in the instruction manual, replace it with a new one. The test batteries that came with the clock may have a shorter life span than regular ones.
• Solar-powered devices may need additional charge to receive a signal. The batteries used in a solar device may also have a limited life span.
• If there is no problem with the batteries, place the clock in a location where reception was possible before and observe it for two to three days. If the signal is successfully received even once during this period, the time should be accurate to within 1s, which should be sufficient to use the clock.
• If you continue to have problems receiving the signal, check if there has been a change in the environment. Is there a TV, PC, fluorescent light, air conditioner or battery charger nearby? All of these may generate electrical noise that can affect the radio-controlled clock.
• If you previously been able to just barely receive the signal, reception may have stopped due to seasonal changes in radio wave propagation. Try to find a location with a stronger signal.
  ・Place your radio-controlled clock near a window facing the direction of the transmission station (Fukushima prefecture in eastern Japan, Saga prefecture in western Japan).
  ・The radio signal is weak underground and in buildings made of reinforced concrete.
  ・Avoid locations near metal objects such as window blinds.
  ・Test reception outside of a building for at least one day. If there is still no reception, the device may no longer be functioning correctly.
  Avoid moving the clock while it is trying to receive a signal.
• Radio-controlled clocks can be affected by weather conditions. Lightning or static electricity may interfere with reception.

• If the radio-controlled clock has an analog display (one with moving minute and hour hands), a changed alingment of the hands will cause the wrong time to be displayed. Please check the manual for instructions how to correct the alignment.
• If the clock has an automatic adjustment for daylight saving time, then this may have caused the incorrect time to be displayed. Please check the manual for the correct setting.
• When a radio-controlled clock is used outside Japan and manually adjusted for the local time zone, it may under rare circumstances still receive the standard radio signal and change back to display Japan Standard Time. In these conditions, it is not possible to use the clock.
• If the minute or hour is displayed incorrectly only occasionally, the problem may be periodic noise. Please check "How can I check the reception environment?" for advice.

Some models of radio-controlled clocks with a date display function require a manual adjustment for leap year information. If this is set incorrectly, then the date will be one day ahead or behind after February 28. Please check the instruction manual to make the correct settings.

Radio-controlled clocks are sensitive to electrical or radio-frequency noise, and require a good reception environment to function.

• If possible, place the clock near a window facing the direction of the closest transmission station.
• Keep the clock away from noise generating equipment (ideally by several meters), such as TVs, PCs, air conditioners, fluorescent lights, AC adapters such as battery chargers and other electric appliances.
• An easy way to check for noise is to use a battery powered AM radio. Set the frequency to the lowest frequency where no radio station is received and listen to the hissing noise that can be heard. If the AM radio is close to a source of noise, this sound will become louder, and may change to buzzing, crackling or gargling sound. This will give you an idea where the noise may be coming from. Receiving the standard radio signal will be difficult in locations where loud noises are heard on the AM radio. Choosing a location with low noise may allow the radio-controlled clock to function correctly.

Please understand that this simple method may not always give reliable results!