The H2OhNo! is a water sensor alarm kit that you build yourself. When water is detected across the sense pins an alarm goes off and an LED starts blinking. If you've ever had a water heater explode or tried to create submersible electronics you know how important it is to be able to detect when water is around!
Underneath the default function of H2OhNo! is a small but powerful development board for the ATtiny85 microcontroller. The board includes a buzzer, LED, a coin cell battery, and the ability to detect analogue and digital sensors. This mixture of parts creates a great low-cost tool to learn how to program and sense things.
This board can be re-programmed to be an Annoy-A-Tron (originally made by Think Geek). Please annoy respectfully, otherwise your board may get demolished.
- Water sensor alarm kit.
- Easy to assemble through-hole soldering kit.
- 1 x H2OhNo! PCB.
- 1 x ATtiny85 (Pre-Programmed).
- 1 x 20mm Coin Cell Battery Holder.
- 1 x CR2032 Coin Cell Battery.
- 1 x Slide Switch.
- 1 x 8-Pin DIP Socket.
- 1 x Super Bright Red LED.
- 2 x Jumper Wires.
- 1 x 0.1uF Capacitor.
SparkFun Stock Code:
Same Day Dispatch
- Orders placed online before 3:00pm Monday - Friday (excluding public holidays and our Christmas shutdown period) are always dispatched the same day provided the goods are in stock. If the goods are not in stock we will endeavour to contact you as soon as possible to discuss a dispatch date.
- If you live on the UK mainland and don't have any large materials or lithium batteries in your order it will cost £3.95 (£4.74 including VAT) if you spend less than £40 (£48 including VAT).
- If you spend between £40 and £200 (£48 - £240.00 including VAT, excluding large materials or lithium batteries) delivery is free to most locations, £12 (£14.40 including VAT, excluding large materials or lithium batteries) to Northern Ireland and £15 (£18.00 including VAT, excluding large materials or lithium batteries) to UK remote locations. For a list of postcodes that will be charged the remote location rate: remote area list.
- If you spend over £200 (£240.00 including VAT, excluding large materials or lithium batteries) delivery is free within the UK.
Rest of the world
- These orders are sent via UPS, and the cost is dependant on the service you choose at checkout. Alternatively you can choose the free collection option and have your own courier collect it from us. International orders can only be shipped to the registered card address. Please note: International orders may be charged import duty dependant on local import laws and duty rates. These charges are usually billed to you directly from UPS.
- Delivery times vary for international orders depending on the service selected and the destination. You can see the delivery time and cost at the shipping stage, or by using the shipping estimator from within the shipping basket.
- If you would like to collect your order, or use your own courier then there is an option you can select during checkout. We do not charge a packaging or handling fee for this service, and you will receive an email when your order has been processed, you can collect half an hour after receipt of this email.
- For information about all of the delivery options we offer see full delivery details.
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