The circuit for the opto's is based on this

 

My problem has been how to transfer a fixed 555 (or whatever) frequency to two opto circuits with 180° separation?

 

The frequency cannot be above 1Khz but thanks for the suggestion

The doubled frequency is NOT the output frequency. It is the frequency that is input to the 50% duty cycle generator. As such, in the proposed scheme for a maximum frequency of 1KHz, one would generate the input frequency of 2KHz. Or a range whose endpoints are double that of the output frequency.

Feed this input frequency into a D flip flop wired as a T (toggle) flip flop. That is, connect notQ output to the D input. Then, the Q and notQ outputs are your alternating outputs.

Much simpler than the circuit you posted. It only used one flip flop.

It would help if you could also generate a timing diagram, so we can validate any suggestions

 

If you want F/2 at (arbitrarily) 0 degrees and 180 degrees, take the signals from IC2A pins 1 and 2. they are complimentary. Tie pins 8, 9, 10, and 11 to GND, and ignore 12 and 13.

Check the 4013 datasheet for its output current ratings, and note that as the output current (either sourcing or sinking) increases, the output voltage margin increases.

ak

 

If you want F/2 at (arbitrarily) 0 degrees and 180 degrees, take the signals from IC2A pins 1 and 2. they are complimentary. Tie pins 8, 9, 10, and 11 to GND, and ignore 12 and 13.

Check the 4013 datasheet for its output current ratings, and note that as the output current (either sourcing or sinking) increases, the output voltage margin increases.

ak

It is not so much 0 and 180°, as 90° and 270° (the peak and the trough), but thank you for your help. It is most appreciated.
I'm gonna follow your suggestions tomorrow (it is midnight here).

 

Good point.

I have been working to schematics, however they are what I have drawn in my notepad and not easily transferred onto a webpage.

The circuit I used earlier for the 555/4013, I lifted from a site and it was this...

It is not the circuit I am looking for, as it clearly states 1/2 a 1/4 frequency.

It does indeed flip and flop, only F/4 is half the frequency of F/2... as mentioned

LM555 with a 50% duty cycle.

 

LM555 with a 50% duty cycle.

*Approximately* 50%, as in post #15.

ak

 

It is not so much 0 and 180°, as 90° and 270° (the peak and the trough),

You are dealing with all square-wave devices and signals, so there are no peaks and troughs in the traditional sense (as with sine waves). The two signals are 180 degrees out of phase with each other, but nowhere in this thread have you indicated that you wanted them 90 degrees phase shifted from the source.

ak

 

It is not so much 0 and 180°, as 90° and 270° (the peak and the trough)

Wouldn't that be done with a "Johnson ring counter"? But it would still not be a sine wave but a square wave.

 

LM555 with a 50% duty cycle.

Hi, as mentio

You are dealing with all square-wave devices and signals, so there are no peaks and troughs in the traditional sense (as with sine waves). The two signals are 180 degrees out of phase with each other, but nowhere in this thread have you indicated that you wanted them 90 degrees phase shifted from the source.

ak

Hi,
Yes, I am aware that peaks and troughs do not occur with square waves (I deleted the 'so to speak' after peak and trough in order to shorten the sentence), I was trying to clarify the situation but seem to have failed in that respect and true, it would have helped if I had clarified the phase degree positions, however this thread was started whilst in the hunt for a duty cycle display and has mutated somewhat as it became apparent that a display was not necessary...

 

Possibly hack one of these.
http://www.ebay.com/itm/0-1Hz-102-4...051856?hash=item1ebaaf07d0:g:jy0AAOSwB09YDh0g

 

The doubled frequency is NOT the output frequency. It is the frequency that is input to the 50% duty cycle generator. As such, in the proposed scheme for a maximum frequency of 1KHz, one would generate the input frequency of 2KHz. Or a range whose endpoints are double that of the output frequency.

Feed this input frequency into a D flip flop wired as a T (toggle) flip flop. That is, connect notQ output to the D input. Then, the Q and notQ outputs are your alternating outputs.

Much simpler than the circuit you posted. It only used one flip flop.

It would help if you could also generate a timing diagram, so we can validate any suggestions

Tried your connection changes and although they are brilliantly simple, they don't seem to work. I only get a frequency from Q once I connect the opto's

Back to the drawing board

 

A complete schematic might help. Draw it on paper and snap a pic to upload if you don't have any schematic rendering software.

 

If you want F/2 at (arbitrarily) 0 degrees and 180 degrees, take the signals from IC2A pins 1 and 2. they are complimentary. Tie pins 8, 9, 10, and 11 to GND, and ignore 12 and 13.

Check the 4013 datasheet for its output current ratings, and note that as the output current (either sourcing or sinking) increases, the output voltage margin increases.

ak

Nice idea but it didn't work and I reckon it blew the chip

That doesn't work

 

A complete schematic might help. Draw it on paper and snap a pic to upload if you don't have any schematic rendering software.

Your suggestion did actually work, until I connected the opto's. Then, only the Q output functioned properly.

I am sorry, but I don't have how to take any pictures.

Try to see this.

A 555 output of say, 888hz and +/- 50% duty cycle. Let's say 49.9%

In an ideal world, the signal from single pin 3 of the 555 needs to enter a HEF4013 and exit as TWO outputs.

I.e. Imagine two LED's connected to different output pins on the 4013.

One lights up, then the other, then the first, then the other... ad infinitum.....

It does not have to use a 555, nor a 4013. It is just that I am in Brazil and that is what I have right here, right now....

I can try to get an image tomorrow.

 

You've told me that doesn't work. You've rather aggressively told AnalogKid that his suggestion doesn't work.

But you haven't told us WHAT doesn't work. We have no idea what you did. We have no reason to believe that you did what we suggested. What we know is something doesn't work. And we likely believe it's not what we suggested.

Put your image where your mouth is. Post a schematic, or I can't waste any more time on this.

 

Your suggestion did actually work, until I connected the opto's. Then, only the Q output functioned properly.

I am sorry, but I don't have how to take any pictures.

Try to see this.

A 555 output of say, 888hz and +/- 50% duty cycle. Let's say 49.9%

In an ideal world, the signal from single pin 3 of the 555 needs to enter a HEF4013 and exit as TWO outputs.

I.e. Imagine two LED's connected to different output pins on the 4013.

One lights up, then the other, then the first, then the other... ad infinitum.....

It does not have to use a 555, nor a 4013. It is just that I am in Brazil and that is what I have right here, right now....

I can try to get an image tomorrow.

The circuit I suggested does exactly that. Mea culpa, I am asking you to post a schematic and I yet to do so. I'll try tomorrow.

If it works until you hook up the opto, then maybe the opto circuit is wrong. But I can't see it.

 

The circuit I suggested does exactly that. Mea culpa, I am asking you to post a schematic and I yet to do so. I'll try tomorrow.

If it works until you hook up the opto, then maybe the opto circuit is wrong. But I can't see it.

It is strange. Both 4013 outputs register 6v and hold a frequency yet only Q triggers the opto's!

It would appear that the pin 2 of the 4013 cannot pass as much current as pin 1

is there an emoticon for scratching your head??

 

You've told me that doesn't work. You've rather aggressively told AnalogKid that his suggestion doesn't work.

But you haven't told us WHAT doesn't work. We have no idea what you did. We have no reason to believe that you did what we suggested. What we know is something doesn't work. And we likely believe it's not what we suggested.

Put your image where your mouth is. Post a schematic, or I can't waste any more time on this.

Blimey, didn't mean to offend anyone.

If my answers were curt it is because my head is in the circuit rather than the forum.

I have been very grateful for both yours and AK's input and suggestions. I am trying to figure out what section exactly is failing to work.

 

Why can't you supply a schematic?

Ok, you can't take a pic. Draw it in MS Paint. Or use an online schematic tool, like https://www.circuitlab.com/ (disclaimer: I have not personally used this tool. Just presenting it as an example of what's available)

I wasn't offended. Just stating that it is difficult/ impossible to help without knowing what you've done.

You mention that you wonder if the pins can pass enough current. Two points. The datasheet will tell you if the pins can pass enough current. The schematic will tell you if you are supplying enough current to the opto.

Try making a schematic.