FOR THE GREENHOUSE

AUTOMATIC TEMPERATURE CONTROL

Here's a good one. An ex-computer fan, a thermistor, relay, transistor and some other stuff and what have you got? An automatic temperature controller for the greenhouse. Pictures and details to follow soon. In the meantime, take a look at the project below.

 

AN AUTOMATIC WATERING SYSTEM

TIMER AND VALVETHE SPRINKLER NOZZLE

Fed up with relying on neighbours to water your plants while you're on holiday. Worry no more. The G4NSJ automatic greenhouse watering system will drown your plants while you lounge around in those Mediterranean bars.

To the left is the timer and water valve for the automatic greenhouse watering system. The picture above shows the sprinkler nozzle inside the greenhouse roof. The shortest 'on' period my timer will set to is 15 minutes. This is rather too long and tends to flood the greenhouse. However, I'm working on a timed relay to deal with this. More on the auto watering system soon.

 

THE GARDEN CONTROL SYSTEM

Pictured below is my garden control centre. The unit monitors the greenhouse temperature and switches an extractor fan on or off. There's a built in rain alarm which is disabled during darkness by a photocell. I don't really want to know if it's raining at three in the morning. I'm about to add an alarm for the two sheds, among various other things.


 

THE G4NSJ CAT GUN

Don't you just hate it when you've dug and raked over that plot of ground ready for sowing and the following day you discover that it's become the local cats' toilet? Here's a very simple but 100% effective method of keeping cats well away from your vegetable plot.

All you need is a PIR Detector, the type used for outside security lighting, and a washing machine water inlet valve. The arrangement is pretty obvious. The PIR Detector 'sees' the cat and energizes the water valve. Not only does the cat get wet, but the hissing sound from the hose sends him fleeing. The pressure in the hose builds up behind the valve and, when it opens, whoosh! It's amazing how a four-second blast of cold water sends cats flying. It's not cruel, and it works.

I've tried pepper dust, lemon juice, jelly-like stuff that stinks worse than the cats... I've spent more money on this junk than the cost of the PIR Detector and washing machine valve. Yes folks, it's true! The homebrew G4NSJ CAT GUN will solve the problem once and for all!

Set the PIR Detector to work in daylight as well as at night. Also, adjust timer to minimum to give a short blast of water. By the way, do remember that mains voltage and water don't mix. You want to scare the cats, not kill yourself!

 

The G4NSJ CAT GUN ready to fire...

BASTARD !!!!

The G4NSJ CAT GUN in action!

I now have another problem with cats - brown patches on the lawn. Because the little devils can’t get anywhere near by vegetable plot, they’re pissing on my lawn and killing the grass. I have two options. Another PIR detector and water valve aimed at the lawn, which would cost more money, or a 50kv electric fence. Which would you go for?

 

THE G4NSJ WATER FEATURE

The water feature, pictured below, wouldn't have been possible without Martin, G8KOE, who kindly supplied the pump at great expense to himself and his family. We are forever indebted, Martin.

THE PISSING LADY

GROWING GERANIUMS FROM SEED

This is simplicity itself. Poke the seeds into compost and wait. Cool, huh?

 

LOOK OUT FOR MORE GARDENING TIPS
Next week's tip... an automatic beer dispenser for the shed.