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3v doubler to 60v. NE2 neon light no data sheet. 100 neon in parallel.

gary350

Well-Known Member
Online search for NE2 Neon light datasheet is all advertisements people selling NE2. How many milli amps is an NE2 ? 50 years ago I read NE2 is 55 volts. Circuit I found shows .5 ma.

I designed this circuit to make 60 volts ac peak to peak secondary toroid winding. If NE2 Neon is .5 milliamps 100 neon lights in parallel will be 50 ma. 2.125W is not much power for a toroid I have 7/8" diameter and larger.

2 D batteries can deliver 8a max. Short circuit = 25.6W. 2W should be ok.

I don't know much about toroids. I have formulas for EI laminate transformers they need a certain number of primary turns to be happy what about toroids? I need a starting point for primary winding is there something better than guessing? I have #24 enamel coated copper wire to wind toroid with.

I did math for circuit to run at 1460 Hz is this ok for a toroid?

Suggestions?

This is a long over dew project I bought these NE2 Neons 30 years ago there is no resistor attached to the neons.





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ronsimpson

Well-Known Member
Most Helpful Member
NE2 Neon ...…….. 100 neon lights in parallel
I do not like the idea of 100 neon bulbs in parallel. The fire voltage varies from one bulb to another.
A typical bulb might fire at 90 volts (peak or DC) and then it will load down the supply to 60 volts. (hold voltage)
Lets say that one bulb fires at 80V and the next one at 81, the next at 82, 83, 84, ,,,,,, to 90V.
When your supply starts up the 80V bulb fires first and steels all the current. No other bulb will fire.
I found a graph that said it might take 1 Amp to get the hold voltage up to the fire voltage.

I think you need a resistor on each bulb. You need a supply voltage high enough to trip the highest voltage bulb. Maybe 100-110 volts.
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gary350

Well-Known Member
Each neon will have a parallel capacitor and a series resistor RC 1 second timing circuit on each light. I forgot to draw those on the neons. This is a randon light generator. I built this 40 yrs ago to run on 120 vac with variable resistor for the whole 100 neons. Now that I think about the neon section I think it has to be DC.

Variable resistor on the 120vac unit made all the lights change speeds it was interesting. The battery unit still might need a variable resistor to adjust it a few volts plus or minus to change light flashing rate.
 
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gary350

Well-Known Member
I need to know about how many turns of #24 wire is needed for the toroid. I remember push pull will be 4 times more output. I don't think 3v can increase 4 times probably current increases. 10 turns on primary needs 150 turn secondary to get 45vac and 63vdc. Do toroids have a watt rating?
 
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Reloadron

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Most Helpful Member
Years ago it was popular to just use an ole fluorescent tube starter which consisted of a small NE lamp in parallel with a capacitor and place a 1 Meg resistor in series with it making a simple Relaxation Oscillator. The circuits I made doing this I just used 120 VAC mains voltage and a single 1N4006 to serve as my rectifier. Half wave was adequate.

For driving a NE2 bulb, but just a single bulb, was to find any old 1K ohm / 8 ohm audio transformer and drive the 8 ohm output side using a little 555 oscillator. The input now output became a 120 volt source which was half wave rectified using a little 1N914 diode.

Here is a pretty cool example of 45 neon lamps each as a relaxiation oscillator.
Relaxiation Oscillator

Ron
 

audioguru

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Most Helpful Member
Your 10k base resistors give a base current of 0.25mA which is much too low. Then the collector current into the transformer will be only 2.5mA. The little 2N3904 transistors work poorly above 100mA and then need a base current of 10mA.
 

gophert

Well-Known Member
Most Helpful Member
A neon is typically AC for full brightness. If you use DC, only one of the two electrodes in the NE-2 bulb will illuminate.

from Wikipedia...

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gary350

Well-Known Member
OK, I need to re think this circuit. I want to play with this a while just to see what I can learn. I have lots of Darlingting NPN transistors, TIP110, TIP122, TIP127, rated 60v to 100v and 2a to 5a & no pin out information?. After reading about Darlington online I learn they are bipolar 2 transistors high gain in 1 package. NO information so far about what they are used for other than high gain 1000 to 2500.

I am not finding technical data of toroids other than they are high Hz devices compared to EI transformers. What does high Hz mean? Is there a minimum Hz toroids need to run at? If torids need to run at 10KHz and up then my circuit needs to osc at 10KHz.

These are the only transistors I have with more power than a 2N3904 expect for 2N3055. I have a 2N3055 circuit it is about 180w from 12v this is crazy over kill. 100 neons need 60v at 50ma = 3w Online says 2N3904 is 200ma 2w. Is that 1w per transistor for push pull? If I change R1 & R2 to 30 ohms 2N3904 circuit will be about 100ma.

I connected a transformer to the circuit yesterday output on secondary winding = .002v on the meter. 100_5726.JPG
 
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audioguru

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Most Helpful Member
If your transformer and multimeter are made for 60Hz then they barely work at 10khz. A high frequency transformer has a ferrite core. The datasheet for a little 2N3904 shows that it works poorly above 100ma and its max power is 0.625W. A base resistor of 30 ohms can be used for a power transistor, or be used to destroy a little 2N3904.
 

gary350

Well-Known Member
I need a 6" x 6" PC board for 100 neon lights like I had 50 yrs ago all I am finding for sale are small boards. I have several 2"x3" not sure best way to connect them to get 6x6 PC board with neons on front & resistors & caps on back ? I need plastic legs like they use on Mother Boards.
 

gophert

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Most Helpful Member
I need a 6" x 6" PC board for 100 neon lights like I had 50 yrs ago all I am finding for sale are small boards. I have several 2"x3" not sure best way to connect them to get 6x6 PC board with neons on front & resistors & caps on back ? I need plastic legs like they use on Mother Boards.
search for 150mm x 150mm (6" no longer exists).
also, the white legs are called "stand-offs".
 

audioguru

Well-Known Member
Most Helpful Member
The simple voltage boosting circuit in a solar garden light uses the same circuit as the one with 170V output by using an oscillator to drive 0.9V to 1.4V pulses into an Inductor to light an LED that needs up to 3.6V. Of couse the current in the Inductor is much lower than in the 170V circuit. Then a transformer is not needed.
 

gary350

Well-Known Member
Circuit does not work. With 2n3904 transistors I had circuit flashing LEDs at 1 flash per second. I changed transistors to TIP122 the LEDs still flash at 1 flash per second. Then I change R & C to 5K the LEDs are both on. Remove LEDs & add toroid transformer almost no out put voltage. Changed R & C to run about 12K then 16K output voltage on toroid transformer .006V. I have a tiny 50 year old audio transformer primary has center tap I tried it still very small almost nothing voltage output. I also changed R1 & R2 to 300 ohms and 30 ohms.

Next I decided to check out my 50 year old parts I pulled them out the the contain they have been in and all I have is 100 NE2 neons. There is a 1000 pack of 1N4007, a pack of 1000v .1uf caps, a 1000 pack of 470K resistors, this was left over from a Marx generator project long ago. I have no caps rated for 60v. Only way to build 100 flashing neons is order caps & resistors. I have lost interest in the project I think I will list 100 NE2 for sale on ebay to get ride of them they need a new home. I think I sell the Marx generator parts too. Been there done that already.

I am still curious about making 60v from 1 D battery so I might build a joule thief with a 2n3055 but first my vehicle needs new rear brakes and both front wheel drive shaft U joints and making clanking sounds they both need to be replaced nothing has grease fittings anymore. Weather in 60s I buy car parts tomorrow and get started. I take my time maybe I be finished by Thurs or Fri. No hurry it is nice bicycle weather.

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