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If you apply 36V to the switching control parts of a 12V flashing relay then it will draw too much current which will make it too hot and it will fry.
The amount of load on a flashing relay usually determines its flashing speed. When the light bulb burns out so the load draws a small current then the flasher flashes quickly.
If you apply 36V to the switching control parts of a 12V flashing relay then it will draw too much current which will make it too hot and it will fry.
The amount of load on a flashing relay usually determines its flashing speed. When the light bulb burns out so the load draws a small current then the flasher flashes quickly.
If I wanted an analog circuit to do the same thing what would be a simple circuit. I really don't want any relay's involved if I don't have to.
I have plenty of power supply's 36vdc left over from old equipment laying around and I could derive the voltage from there and build a circuit that could switch it. Off and On.
I have an old yoke from a picture tube I wanted to just pulse the 36v through it at a frequency.
If I wanted an analog circuit to do the same thing what would be a simple circuit. I really don't want any relay's involved if I don't have to.
I have plenty of power supply's 36vdc left over from old equipment laying around and I could derive the voltage from there and build a circuit that could switch it. Off and On.
I have an old yoke from a picture tube I wanted to just pulse the 36v through it at a frequency.
This isn't for your car I take it. You could use a relaxation oscillator using an LM339 to drive a relay on/off through a transistor, depending on your coil resistance. You could use an LP339 for extra sink current. A 555 timer might work also with the proper voltage reg. What frequency are we talking here?
This isn't for your car I take it. You could use a relaxation oscillator using an LM339 to drive a relay on/off through a transistor, depending on your coil resistance. You could use an LP339 for extra sink current. A 555 timer might work also with the proper voltage reg. What frequency are we talking here?
I'm sure there are relay speed-up circuits that apply a high current through a coupling capacitor just long enough to speed closure but not have a high steady-state current go through the coil.
I like to get spare parts from used equipment and such I'll see if I can get something from an old vcr or tv. I used to work for a Company that built Shooting Ranges and they had old Circuit boards with 12vdc relay's on them but not anymore.
I'll let you know when I get one. For the time being I'll try the 12vdc relay from an old car to see if it gives me the response I want.
There is nothign wrong with applying 36V to a 12V relay as long as the voltage is reduced soon afterwards. It will make it switch faster and is a good idea but you need to be careful. For example if you apply 36V continiously, then reduce the duty cycle to 25% no harm will be done.
There is nothign wrong with applying 36V to a 12V relay as long as the voltage is reduced soon afterwards. It will make it switch faster and is a good idea but you need to be careful. For example if you apply 36V continiously, then reduce the duty cycle to 25% no harm will be done.
It might cause the relay to chatter and it's a bad idea anyway since the transformer's core will saturate if large currents are drawn with a half wave rectifier connected.
My idea required the use of a microcontroller of 555 timer to do PWM.
If you just want a magneti field, then why not just wind an electromagent.
It might cause the relay to chatter and it's a bad idea anyway since the transformer's core will saturate if large currents are drawn with a half wave rectifier connected.
My idea required the use of a microcontroller of 555 timer to do PWM.
If you just want a magneti field, then why not just wind an electromagent.
To much work when I have one already from the TV set. I figure if I just put the half wave directly on the Yoke Coil it will create the affect I want. What do you think.
I didn't want to involve the 555 timer because I have no programing equipment or skills. I would like to play with it in the future when I have more time. Just like now go to go again. Be back tomorrow maybe if work will let me.
The closest thing to it was when the Engineers where I used to work would create a HEX file and I had to load it from the programmer.
They used some old code because the Owner of the company was to worried someone would steal it or something.
To much work when I have one already from the TV set. I figure if I just put the half wave directly on the Yoke Coil it will create the affect I want. What do you think.
I didn't want to involve the 555 timer because I have no programing equipment or skills. I would like to play with it in the future when I have more time. Just like now go to go again. Be back tomorrow maybe if work will let me.
The closest thing to it was when the Engineers where I used to work would create a HEX file and I had to load it from the programmer.
They used some old code because the Owner of the company was to worried someone would steal it or something.
A little confused about the statements regarding the 555. This chip has no memory, if that's what you were meaning. To design an oscillator with variable duty cycle control is no big deal. In fact, if you refer to the data sheet, https://www.electro-tech-online.com/custompdfs/2008/09/LM555.pdf,
you will find applications for an astable and PWM circuits. There's nothing to program unless you are using a trigger to "fire" the timer using a µC. Perhaps this is what you meant by programming and the .hex file that was provided to you. If your a novice and can read a schematic, as a novice, you shouldn't have any problems.
A little confused about the statements regarding the 555. This chip has no memory, if that's what you were meaning. To design an oscillator with variable duty cycle control is no big deal. In fact, if you refer to the data sheet, https://www.electro-tech-online.com/custompdfs/2008/09/LM555-1.pdf,
you will find applications for an astable and PWM circuits. There's nothing to program unless you are using a trigger to "fire" the timer using a µC. Perhaps this is what you meant by programming and the .hex file that was provided to you. If your a novice and can read a schematic, as a novice, you shouldn't have any problems.
So, is RL off of Pin 3 out to ground is where I put the Relay Coil ? When I buy a relay I would need to know the resistance in order to control it. That is so I don't exceed the 200ma. The relay should be a 12vdc voltage rating with the right resistance.
So, is RL off of Pin 3 out to ground is where I put the Relay Coil ? When I buy a relay I would need to know the resistance in order to control it. That is so I don't exceed the 200ma. The relay should be a 12vdc voltage rating with the right resistance.
Yes, you can tie the relay to either the 12V rail or ground at pin 3. Put a diode in parallel with the coil to suppress the bemf. The 555 uses a push-pull configuration.
Yes, you can tie the relay to either the 12V rail or ground at pin 3. Put a diode in parallel with the coil to suppress the bemf. The 555 uses a push-pull configuration.
Try one of these on-line 555 calculators: **broken link removed**
Some starting values for you:
R1 = 2.2K (Enter as 2200)
R2 = 100K (Enter as 100000)
C1 = 10uF (Enter as 10)
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