50 watt audio amplifier, 50 hz sine wave generator, and a 30 or so volt power transformer that can be wired for either 120 or 240... use the transformer backwards with the secondary driven by the amplifier, and the primary will be your 230V output.... back in the 1970s, Sony had an application note on using one of their amplifiers as a variable frequency line voltage source...
Thanks les Jones for clarifying that. What should I do for voltage then? Should I use 2 outlets out of phase for 240 volts ac, or should I connect the middle electrode to the other one for the lower striking voltage? Which would be easier? (I don't really want to have to do too many modifications to the circuit)
Here is one way of adding an extra stage to one of the divide by 5 counters.
I've added to the one on the right, but you could equally well modify the one on the left. The red box shows where the change is. I've shown the frequencies that you will get with a 60 Hz supply.
You should connect using an isolation / step-up transformer like the one that I linked to in post #22. Then you can run from a normal 120 V outlet.
The Voltage You can Increase by a Transformer - That should be no Problem.
There is an 100mA Fuse in the input so the maximum Power could be 22W.
To get 1Hz I would use a Semicoductor divider with an Clock Crystal - Like the CMOS 4060 chip with an Crystal.
The Oszillator is included into this Chip.
This Chips work up to 12 or some Types 15V
You only have to figure out the 3M3 Ohm Resistor and feed the following line with the 1 Hz Signal.
What signal amplitude there has to be, You should measure before reconfigure.
When Powering up the Clock the Semiconductor could be go fail, because ther could be a High Voltage puls at the 1Hz Line
I would insert a Z-Diode there and a Resitor to avoid this.
View attachment 130192
Here is one way of adding an extra stage to one of the divide by 5 counters.
I've added to the one on the right, but you could equally well modify the one on the left. The red box shows where the change is. I've shown the frequencies that you will get with a 60 Hz supply.
You should connect using an isolation / step-up transformer like the one that I linked to in post #22. Then you can run from a normal 120 V outlet.
You could add a second small transformer with a secondary voltage of about 24 volts and connected it in series with the original transformer secondary. So if the original transformer gave 210 volts you would now have 235 volts. Bear in mind that the mains voltage can vary so this will cause the secondary voltage to vary.
If the circuit is that critical on voltage then consider adding voltage stabilisation. I remember when I was a teenager inn the late 1950s there were gas discharge voltage stabiliser valves (Tubes.) I seem to remember they were available in a range of voltages. One part number for these was OB2WA. This would suit your requirement to use very old technology.
The transformer that I linked to has 115 / 230 V input windings and 115 / 230 V output windings, so the input can be arranged for 115 V and the output can be arranged for 230 V, and there is no need to turn the transformer around.
Any small transformer like that will have a significant output voltage change when loaded. It's called the regulation of the transformer.
That one has a regulation of 25%, so you could well get the opposite problem of the output voltage being too big as I would be expect it to be 1.25 *230 = 288 V with no load.
If you did turn the transformer around, the output voltage would be likely to be a lot lower with no load, and still fall by 25% at full load.
It's designed to be 230 V (or 400 V primary) and 120 / 240 V secondary, so you would have to turn it around.
The advantages of it are:-
1. It has better regulation, of about 10%, and as it would only be loaded to around half its full load, it's open circuit voltage will only drop by about 5% when you the neon clock is connected.
2. It has a +15 V connection and a -15 V connection on the primary winding, that you will be using as a secondary. That will allow you to chose the voltage that is what you want.
Keep everything away from the 400 V connection if you do use it.