# Powering neon indicator lamp from battery

I would like to power neon lamp like NE-2 from low DC voltage like 1.5 V battery.

Is it possible to boost low voltage like that to 85-120 volts which is needed for neon lamp?
And can i use blocking generator schematics for that, or it will not work and have to use something with MOSFET like this?

I'm a beginner in electronics so i'm trying to keep schematics for this as simple as possible (less components and easier to assemble) even if it will be less effective.

• Go study how standard coil-based spark generation systems work in automobiles and apply this same step-up transformer technology to your problem. It uses a very simple principle of inductive kick-back on the primary of the ignition coil getting multiplied by the high value turns ratio to the secondary. 12 volts to 5,000 volts. You shouldn't have too many problems turning 1.5 into 100. – FiddyOhm Oct 30 '16 at 12:25

Here is one more for you to consider. There are many ways to do this. Basically you have to convert the 1.5V DC to ac. Multiply the AC. If you want, you can convert it to back to DC. Converting here is done with a multivibrator. You can probably improve on the one here. In this circuit there are two methods to multiply the voltage. One is a transformer. The other is voltage multipliers. This circuit will provide DC.

I saw your comment about getting the tansformer in the previous answer. Jameco is and online electronic parts supplier. If you search Jameco, you will find that transformer. The transformer in the circuit here is from Coilcraft. You may be able to get one as a sample. If not, I think that cost under two bucks. If you decide to try to build this, make sure you check the voltage rating on the part on the high voltage side. I did not.

• Why is there a voltage multiplier in the circuit while the transformer could do the same job ? – tigrou Oct 31 '16 at 0:18
• Tigrou, This was just a way to show that multiplication could be also done in conversion to DC. Coilcraft has a 1:90 and 1:100 transformer in the same family. I built a few oscilloscopes in the 70s that use multipliers like this. If you need higher voltage DC, it can be a useful thing to know about. – owg60 Oct 31 '16 at 0:57

Try this:

simulate this circuit – Schematic created using CircuitLab

You may have to adjust the resistor values to get it to work well.

The transformer is an audio high-to-low impedance-matching type. It is usually used as a output transformer in class-A audio output stage, to drive a small speaker. Here, we are using it "in reverse".

• As i see here, this is very specific transformer. I doubt that I can find something like this in my area. – after Oct 30 '16 at 21:13
• Rich, forgive me if I'm missing something here. The turns ratio on an transformer is related to the square of the impedance. So I think the voltage is only being multiplied by 11. Is there some additional multiplication going on that I'm not seeing. – owg60 Oct 31 '16 at 0:16

A switching power supply can do what you want. A flyback converter is a good configuration to look at for this purpose. Keep in mind that a neon bulb becomes much more conductive once started, and takes a much lower voltage to sustain. A flyback helps here since the power transfer is inherently limited, and it works over a reasonably wide voltage*current combination.

• As i know, using flyback means making custom transformer, which is difficult. – after Oct 30 '16 at 19:18
• I see a lot of cheap convertors from like 3 volts to few kilovolts looking like this and on the inside it has boost circuit on bipolar transistor like this and multiplier If i'll separate boost circuit, is it possible to make it's output close to 120v i need? – after Oct 30 '16 at 19:40
• @aft: Transformers suitable for such a power supply are available off the shelf. A POE transformer isn't really the right voltage ratio, but you could probably make it work. A basic boost converter is also possible, but more tricky at such a high voltage ratio. It depends on how much you know what you're doing. – Olin Lathrop Oct 30 '16 at 20:04