transformer

[daviddoria]

the stun gun project thats been floating around here called for a 200k to 1k mini audio transformer. i finally got my hands on a
45-706
it has 4 wire leads. on the sheet it says
pri.
start-red finish-blue
sec.
start-yellow finish-green

here is the circuit drawing:
https://www.electro-tech-online.com/threads/simple-lie-detector.40/

here is the transformer data sheet:
https://www.calrad.com/download/45ser2.doc

which leads do i connect to where?

thanks
david

 

[Sebi]

Choose as You want, because no feedback.

 

[daviddoria]

so i can put any of the 4 in any of the 4 possible positions?

also, i dont know if i have a CT or not.. i guess that is center tap huh?

does this matter ?

 

[Phasor]

No, you definitely can't put any wire in any place!!!

The primary is the 200K side, and the secondary is the 1K side. It doesn't matter about the center tap, as in the schematic, the top of the 1K isn't connected anyway.

The stun gun uses the transformer in 'reverse'. The 1K (yellow/green) should be connected to +9V and Q1. The 200k (red/blue) is the output via R4.

Yellow/Green are interchangeable with eachother, as are Red/Blue. But you can't interchange the primary with the secondary.

 

[Sebi]

Yes, of course i think only start and finish interchangeable.

 

[daviddoria]

awesome

so has anyone built this... it seems to deliver something to the effect of the the strength of putting a 9V on your tounge.. just on your arm.

does that sound about right? or did i do something wrong?

also, what is a voltage doubler circuit consisting of? just a couple diodes and some caps right?

david

 

[bogdanfirst]

a doubler circuit consists of 2 caps and 2 diodes.
but you have high voltage for output, so make sure that the capacitor can handle the voltage as well as the diodes.
the diodes musnt be high current, but they must support high reverese voltage.

 

[daviddoria]

hmmm what do the diodes actually do there?

can i just stick a couple caps after the transformer? will they charge and make it a stronger shock?

 

[Phasor]

Just putting a capacitor on the output of the stun gun will not improve it - it will change the shape of the output wave, and probably will decrease the output voltage, by loading the transformer.

The diodes in a voltage doubler are quite necessary - Let me use an analogy - Imagine it as building a two-storey house - except we are building it a strange way...

Build one storey first (on the ground). Now jack it up into the air, and build the the lower storey underneath it. You need something to hold the top storey up, while you build underneath. This is what the diodes do.

Voltage doublers can be added together to make voltage triplers, quadruplers, and so on.

 

[bogdanfirst]

or, ill explanin in another way.
the output of the ransformer is ac.
when the current flows in one way it charges on of the capacitor and the out voltage is obtained by adding the voltage on the other capacitor and the input voltage.
when the current flows the other way it charges the other capacitor and the voltage is obtained by adding the voltage on the other capacitor and the input voltage.
so in one semiperiod one cap is charged the other is used to doube the voltage. on the other semiperiod - viceversa.

 

[Gothrich]

Looking at the circuit diagram i noticed that the IC chips pins are numbered 1,2,6,7,4,8,3,5 (clockwise from bottom left). I have not done electronics for quite some time. do the numbers refer to the actual pins to connect on a 555 timer or has this schematic been simplified to show the connections of components to the pins
i.e
2 and 6 connected (trigger and threshold connected)
5 to C2 (control voltage connected to 0.01uf)

I would appreciate the help.

 

[Gene]

The pins are actually numbered sequentially on the physical chip. The schematic has been altered for clarity.

 

[Gothrich]

Thanks.