Showing posts with label DIY. Show all posts
Showing posts with label DIY. Show all posts

Tuesday, October 2, 2012

A power amplifier for the serious garage door opener

While my serious garage door opener works nicely and reliably, it's output power is "only" 10 dBm (10 mW). It is able to open the garage door from about 100 m -- this is clearly not enough.

So I thought an impressive looking garage door opener needs an impressive amount of RF output power as well. And I found a wonderful solution to that problem, the SKY65116 chip module.

It provides up to 2 W of output power from 390 - 500 MHz, 30 dB of gain and its input and outputs are matched to 50 Ohm. In fact it contains a third matching circuit between the internal pre- and power-amplifier  It can be put into standby mode drawing only a few uA and thus can be left connected to the battery. When running at full blast it draws 1.2 A at 3.6 V, so its efficiency is about 50 %. Not bad at all!



Saturday, September 15, 2012

The serious garage door opener

Garage door openers are handy little gadgets. Most of them are cheap chinese plastic crap though. This one definitely isn't. It started by collecting parts from my favorite electronics shop: the dumpster.


An old emergency shutdown switch makes the perfect case with a seriously big red button.