Hello everyone!
I‘m in the process of Building my own gear, quite basic, and think about making it as minimalistic (looking 🤓) as possible. (I‘ll end up with some rather fancy stuff inside but that‘s ok.)
Here‘s what bites me for the moment: I‘d like to combine the power on/off and the volume-knob, just like in these old pocket-transistor-radios... on the other hand, I‘m drooling over those ladder-attenuators...
Can they be brought together somehow (electronically, mechanically, ...)
Thanks already!
Da.
I‘m in the process of Building my own gear, quite basic, and think about making it as minimalistic (looking 🤓) as possible. (I‘ll end up with some rather fancy stuff inside but that‘s ok.)
Here‘s what bites me for the moment: I‘d like to combine the power on/off and the volume-knob, just like in these old pocket-transistor-radios... on the other hand, I‘m drooling over those ladder-attenuators...
Can they be brought together somehow (electronically, mechanically, ...)
Thanks already!
Da.
I guessed so. 🙂
I rather imagined something like triggering a relay, electronically or mechanically (with a sort of a "dent"). How are those made?
I'm convinced a solution is possible, but I prefer to look around before reinventing stuff ...
on/off is combined with the band-selector:
https://images-na.ssl-images-amazon.com/images/I/517gbOJOjvL._AC_SL1200_.jpg
on/off is combined with the volume:
https://ae01.alicdn.com/kf/HTB1DrtO...-nger-Kurzwelligen-Batterie-Powered-Tuner.jpg
I rather imagined something like triggering a relay, electronically or mechanically (with a sort of a "dent"). How are those made?
I'm convinced a solution is possible, but I prefer to look around before reinventing stuff ...
on/off is combined with the band-selector:
https://images-na.ssl-images-amazon.com/images/I/517gbOJOjvL._AC_SL1200_.jpg
on/off is combined with the volume:
https://ae01.alicdn.com/kf/HTB1DrtO...-nger-Kurzwelligen-Batterie-Powered-Tuner.jpg
How about a rotary encoder cw momentary contact push switch?
The fancy stuff inside would need to include a microprocessor!
The fancy stuff inside would need to include a microprocessor!
Yes! (even less ideas how to make this work, though)
Or, if there'd a way to "turn it on" the contact push switch could then also be used as input selector (instead of power on/off)?
Plenty of tutorials online for doing all kinds of things with an Arduino. It's not as difficult as you might imagine [emoji106]
Another trick would be a cam which triggers a microswitch on a low power independent "standby" DC supply, the microswitch activates a larger relay on the mains input for the main transformer. There's actually many ways you could skin this cat...
If it's "basic" and "minimalist" then why even have a power switch? Let it come on when it's plugged in.
It's ok ONLY if that is a battery-powered device or you put a switch in low-voltage secondary power lines, isolated from primary mains (mains are always connected).
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Thanks for the advice!
I was thinking of a tricked design: Having the attenuator-knob mechanically switching the power-switch... Or, like, have the Attenuator trigger a relay which switches the mains on/off...
I'm sure you can read out of these that I am no expert... and, I know it's not thought through, but I'm "having visuals". I may try to build something (someday).
da.
In the tube TV's and radios, this combined switch and volume control was very usual, and no troubles still in our 220VAC lines.
Old tube TV were far from today safety standarts. So they are not a good example
In modern audio-devices, usually it is used a way with auxiliary power supply and low-voltage low-current switch (button), which operates a power relay or semicunductor switch, which turns on main power supply.
In modern audio-devices, usually it is used a way with auxiliary power supply and low-voltage low-current switch (button), which operates a power relay or semicunductor switch, which turns on main power supply.
Yes, but it generates other problems, like power spent continuously from this stand by circuitry. I prefer the classic switch.
You could use the switch on the volume control to activate a relay, with DC. No hum.
Another option, if you go for a stepped attenuator, have an extra deck on it at some distance behind the signal switching decks, possibly with a metal screen in between. Or also here, use the relay trick.
Jan
Another option, if you go for a stepped attenuator, have an extra deck on it at some distance behind the signal switching decks, possibly with a metal screen in between. Or also here, use the relay trick.
Jan
I have built circuits in the past that used a battery to initially turn on the power relay, which was then switched out by one of the relay contacts once the ac power supply came on. This way there is no current draw at all until the power switch is turned on and since the battery supplies only a short pulse of power it lasts a very long time before needing replacement.
Take care,
Doug
Here is an example of a circuit to do this.
K1 is a relay with a 9 volt rated coil and needs to have a sufficient contact rating for powering all of the desired power supplies. The LM311 comparator senses the power switch position and activates the relay using the 9 volt battery. The 100uF capacitor across the relay coil holds it on until the AC powered 9 volt power supply can take over. The 9 volt power supply actually supplies about 11 volts, ensuring that it powers the relay and circuit instead of the battery. I have had the batteries in these power supplies last many years before requiring replacement.
Take care,
Doug
K1 is a relay with a 9 volt rated coil and needs to have a sufficient contact rating for powering all of the desired power supplies. The LM311 comparator senses the power switch position and activates the relay using the 9 volt battery. The 100uF capacitor across the relay coil holds it on until the AC powered 9 volt power supply can take over. The 9 volt power supply actually supplies about 11 volts, ensuring that it powers the relay and circuit instead of the battery. I have had the batteries in these power supplies last many years before requiring replacement.
Take care,
Doug
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