Cow feeder!!

[ericgibbs]

You had question marks so I thought you had some question about that. Guess you were referring to whether anyone had a problem with leaving CIN unconnected.

Certainly a particular CMOS device may allow operation without all the inputs tied, at least for a while, but subtle changes in the circuit, such as from moisture or noise pickup, could lead to erratic (and hard to trace) problems at a latter date. There are reverse-biased input protection diodes to both Vss and Vdd on standard CMOS circuits but I wouldn't depend upon those to provide a definite logic level as the leakage goes in both directions.

I have been successfully using CMOS logic in my designs/products since they first came on the market, before that 74LSxx and before that 74xx series, DTL, RTL ........

I would suggest that you advise the OP, not me, on any changes that you consider applicable to my circuits.

As I suggested in this and other Threads, post your version of the circuit/s that answers the OP's requirements.

 

[gibby106141]

After I posted last night I did make a few changes and managed to get it going but only counting up or down to 15 - I'm at work at the moment so will try again tonight - could you just look at the attachment I'm ut trying to work out the pin config, as everywhere I look they seem to be different - I've put a table together comparing Yenka apbbreviations to your circuit and also the internet ref.

Thanks for your help, I know this is a fault on my part, and I will let you know tonight how I get on.

Regards

Mark

 

[ericgibbs]

After I posted last night I did make a few changes and managed to get it going but only counting up or down to 15 - I'm at work at the moment so will try again tonight - could you just look at the attachment I'm ut trying to work out the pin config, as everywhere I look they seem to be different - I've put a table together comparing Yenka apbbreviations to your circuit and also the internet ref.

Thanks for your help, I know this is a fault on my part, and I will let you know tonight how I get on.

Regards

Mark

hi,
Your pin conversion chart looks OK.

I will try to do a circuit diagram using ExpressSch drawing program and post it this eve. [UK]

Download the free ExpressPCB circuit and pcb drafting program from the web, then you can open and edit my posted diagram...

 

[ericgibbs]

hi,
This is the expresssch program drawing of the circuit.

If you have downloaded expresspcb, you should be able to open the .sch file OK.

Note:
I have added a Manual feed button, while pressed the Relay will energise.

 

[alec_t]

Presumably the left end of the 10nF cap is grounded and pin 8 of 555 goes to +12V ? The triangle symbols at those points in the schematic are somewhat ambivalent.

 

[ericgibbs]

Presumably the left end of the 10nF cap is grounded and pin 8 of 555 goes to +12V ? The triangle symbols at those points in the schematic are somewhat ambivalent.

Hi,
I missed that one, should be marked as 12V, the rest of the 0V and +V I took the trouble to notate.
There is a difference if you know expesssch, the 0V is a 'triangle' and the +V a 'spike', do you use express.??

Like the choice of the word 'ambivalent'

 

[ericgibbs]

Hi,
I missed that one, should be marked as 12V, the rest of the 0V and +V I took the trouble to notate.
There is a difference if you know expesssch, the 0V is a 'triangle' and the +V a 'spike', do you use express.??

Like the choice of the word 'ambivalent'

EDIT: I would also expect the OP to be aware of the basic configuration of 555.

 

[ericgibbs]

EDIT: I would also expect the OP to be aware of the basic configuration of 555.

I have also made customised symbols for the +V rails, BUT as the OP hasn't got those, I used the standard symbols.

 

[ericgibbs]

hi alec,
For some unknown reason my Edits are creating new posts.???

Test.

 

[gibby106141]

Eric,

Didnt answer your earlier question - but Im in cumbria (where all the cows are!!)

I've made the changes to the switch arrangement on the Yenka version I've got running, again the notation on the express software appears to be a little different but seems to work out as follows

Pin 1 - express = PREEN, Yenka = LD, First circuit you provided = PE

With the link from the output of the lower gate to yenka LD the circuit does not work - this may be something to do with yenka possibly??

With it removed the circuit does a count of 15 and then resets - you also seem to have to press the momentary push button twice to get it oscillating - again this may be something to do with Yenka??

Thank you for the manual feed - thats a very good, welcome addition, sometimes you do need to do that!!

Ive enclosed a screen shot again!!

Regards

Mark

 

[ericgibbs]

hi Mark,
I think it must be something to do with Yenka sim.

Did you download the expresspcb from that link I posted, you can then use it to see the sch file I posted.

The circuit as drawn is still feeding the cows on the test bread board at my end.

BTW:
My Son and I have a small farm in RSA, no cattle, only sheep and pigs.

 

[gibby106141]

Eric

Yes I downloaded and viewed with the program you suggested

I'm going to go and buy the components tomorrow so I can try it myself

If this really works it will have saved us a significant amount of money for replacing some equipment in our milking parlour I honestly can't thank you enough for the help you've given me

Regards

Mark

 

[crutschow]

I have been successfully using CMOS logic in my designs/products since they first came on the market, before that 74LSxx and before that 74xx series, DTL, RTL ........

I would suggest that you advise the OP, not me, on any changes that you consider applicable to my circuits.

As I suggested in this and other Threads, post your version of the circuit/s that answers the OP's requirements.

Generally commenting on suggestions in other posts seems to be commonly done in this forum and I didn't understand that you considered that bad form. I guess I'm a little dense. My apologies if I've offended you.

In the future I will try to limit my discussion strictly to the op questions and not directly comment on anything you post.

 

[KeepItSimpleStupid]

Look at the IDEC Smart Relay as an option. It's basically a very small PLC (Programmable Logic Controller)

 

[alec_t]

There is a difference if you know expesssch, the 0V is a 'triangle' and the +V a 'spike', do you use express.??

Never used it (convince me of its merits; I use Eagle). From what I've seen above I prefer the schematics that LTS churns out.

 

[ericgibbs]

Never used it (convince me of its merits; I use Eagle). From what I've seen above I prefer the schematics that LTS churns out.

I would never try to convince you of its merits or otherwise, the reason I took the trouble to draw a sch diagram is so that the OP could get a clear idea of the pin numbers, which unfortunately LTS dosnt show.
Also a sch drawing would be easier for the OP to edit rather than having to learn LTspice.

 

[alec_t]

Understood. There's a lot of 'wouldn't it be nice if....' I'm finding about LTS as I climb its learning curve.

 

[gibby106141]

Finally got the bits to try this tomorrow have made it up on vero board if i can get it working ok is there anyone who can help me transfer the circuit to a propper pcb which i could get made somewhere?

Regards

Mark

 

[ericgibbs]

Finally got the bits to try this tomorrow have made it up on vero board if i can get it working ok is there anyone who can help me transfer the circuit to a propper pcb which i could get made somewhere?

Regards

Mark

hi Mark,
Try member 'Boncuk' , he is pretty good with PCB artworks.

E

 

[Boncuk]

Hi Mark,

I just received a message from ericgibbs asking me to check out your thread and possibly give a helping hand with a PCB design.

Of course you are welcome. I'll do my best to make the design single sided (to save costs) and make the design a way that allows easy and error free population of the board.

Just PM me your email address to forward the design. It will take me one (max two days) to finish the design, depending on parts I'll have to design to fit for the Eagle layout editor.

Regards

Boncuk