Enoki found that Qiachip wireless transmitter works at 3.3V.
The Qiachip cannot transmit at the range of 15m, but it works across a glass window. it will be able to monitor water tank level outside of window or veranda.
Qiachip のワイヤレストランスミッタが 3.3V で動作すると知った。
伝送距離 15m は得られなかったけれども，窓もしくはベランダ越しに水位のモニタが可能だろう。
Brand Name: QIACHIP
Use: Electric Door
Use: Automated curtains
Wireless Communication: RF
Model Number: RX480-E4 Receiver & TX118SA-4 Transmitter EV1527 Encoding
Support APP: No
Enoki wired the transmitter with DC-DC converter on the cut Akizuki's universal board (48x47mm), as shown in Photo1.
Enoki also wired the receiver on Sunhayato's universal board ICB-86G.
The transmitter standby current is constant 2.1uA, when supply voltage varies 3.50 to 6.02 V except for 2.3uA (3.32V).
The receiver dissipates 3.94 mA at 5V.
And the consumption current increases to 6.94 mA, when it receives the transmitter signal.
The both currents were measured by Enoki's scratch power supply and DMM PC510.
The receiver power was supplied with a booster, as shown in Photo2. The booster steps up 3V D (R20) batteries to 5V.
Enoki carried it in his hand and walked in and out house. The LED turns off, when the receiver cannot pick up the radio wave. the transmitter emitted on the steel desk.
Enoki's water level sensor has a photo coupler which turns on a wireless door bell. The cacazi and Revex door bell informed well.
The Qiachip hardley transmits within Japanese wooden house. It can use in room or across glass window only.
You may monitor water level of tank for plants or something.
Although Qiachip declares that it works at 3V, the actual working consumption current doesn't saturate below 3.5V as shown in Figure1. The range may increase at 5V.
© enoki.net 2020 March 2