[GreenKeys] Auto start circuit

[Ralph Mowery]

I would build something that could detect the space frequency and every time that cycled set another circuit with a timer to last for 1 minute or some other desired time to hold in a relay for the motor.

This could be something as simple as a 567 tone decoder driving a 555 timer.

Or you may be able to program one of the Arduino boards to detect the tone and set a timer to hold in a relay for however long you want.

If you already have a demodulator that has some output for just the space signal, all you need is a timer and relay.  The 555 IC should do it, or the Arduino processor would.  

Ralph ku4pt



-----Original Message-----
From: greenkeys-bounces at mailman.qth.net [mailto:greenkeys-bounces at mailman.qth.net] On Behalf Of Jeffrey Angus
Sent: Wednesday, August 05, 2020 4:09 PM
To: Jim Haynes
Cc: greenkeys
Subject: Re: [GreenKeys] Auto start circuit

On 8/5/20 2:30 PM, Jim Haynes wrote:
> There are the designs used in the ST-5 and ST-6 demodulators
> of Irv Hoff, schematics widely distributed.  You want something
> with a timer so that once it decides to turn the motor on it keeps
> it on for a while even if the signal that started it goes away.
Pretty much yes, but this is for a solid signal, like i-Telex.



-- 
"I am a river to my people."
Jeff-1.0
WA6FWI
www.foxsmercantile.com