Experiment 06 with IR indicators:

Testing IR remote controls

Using the IR indicator IRI 1100, TV remote controls and their batteries can be tested in a very simple way.

Required equipment

IR remote control (TV, VCR, etc.)
IR indicator: IRI 1100
Daylight source

Safety measures

none

Preparation: Charging

Expose the IRI 1100 to daylight or fluorescent light prior to use (charge). The charging time depends on the intensity of the exciting light. Normally, it takes less than a minute. Important is the blue part of the charging light. Incandescent bulbs are inappropriate because of their high IR level. It would discharge the card simultaneously during charging.

Realization

Hold the active surface of the IR indicator card against the frontside of the remote control (with ambient light shielded or in darkness). If there is IR radiation, the active surface will emit visible orange light. As soon as the IR stimulated emission decreases, recharge the IRI 1100 as described above.

If there is no IR light detectable when button is pushed (Attention: not all buttons must cause an IR emission), renew batteries. Otherwise repair or renew the remote control.
If the IR indicator emits intense light (for a short time) when button is pushed and then becomes quickly dark, and if this effect is reproducable after a short break without recharging the card, this would be a hint for used batteries. To be really sure: the battery cannot recover during very short emitting breaks. In that case the IR beam remains weak at the next pressure of button.
If the remote control emits IR radiation without pushing a button, remove battery and replace it after about one minute. Should this measure be without success, remove battery and repair remote control or renew it.
Conventional remote controls emit visible pulsed IR light. If such a remote control emits continuous light, the battery might be too weak, or the remote control is defective.