For many years the simple 555 timer has actually been made use of in a lot of unanticipated locations, but there’s a project from [Frank Latos] which we think may be a first On an item of stripboard rest a set of 555s, as well as as opposed to the typical passives there are a collection of LC circuits. This is no timer, rather it’s a CW (Morse) transmitter for the 80 metre amateur radio band.
One 555 is set up as a comments oscillator with a toroidal transformer with a tuned circuit to establish the regularity of oscillation. The various other takes an upside down input from the oscillator to generate free push-pull outcomes from both 555s, which are fed to an additional transformer that subsequently feeds a low-pass filter as well as therefore the antenna.
Free-running squarewave oscillators of this kind are not uncommon for the reduced HF bands, yet we assume this is the very first 555 layout we have actually seen. As revealed it does not generate much in the method of RF power, yet bearing in mind half-decent electric motor motorists utilizing a 556 twin timer we assume that option of among the much more effective 555 versions could provide some even more strike. We compliment his creative thinking though, as well as wish he can obtain that critical entrance in the log to confirm it functions.
If you wonder concerning low-power radio procedure, it’s something we have actually discovered prior to.