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555 pcb
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MarkF:

--- Quote from: m3vuv on September 02, 2019, 01:55:59 pm ---ive got so called easy eda,seems a bastard to use the disc ceramic has about a 5mm footprint,size of the board isnt an issue,trust me if i could do it myself i would,i find veroboard messy and too time consuming,bear in mind i may have hundreds of these to make,didnt realise i was asking the earth,i would think a simple track layout foe someone who is good with pcb software would find it a 10n mins job,ive done a few freehand but the board marker dissolves in the etchant,didnt realise i was asking the earth!!.

--- End quote ---

Nothing is simple when you don't have a complete specification!

I takes so long because:

* No footprints or actual part numbers are specified.
* No off board connections specified (i.e. no component specified or no pad size specified or no wire gauge specified).
* Through-hole or SMD not specified.
* Desired board size and shape would be helpful as a target.
* A complete schematic with the parts to be included on the board is mandatory.
* No connector types specified.
* Time frame too short.  Allow at least 4 to 6 weeks for layout and manufacture (Unless you want to pay massive shipping cost). 
For this small board, allow more than 4 weeks for standard delivery.  Having this board manufactured for a Sept 5 demo is totally unrealistic.We can not read your mind.


Work out your PCB design software computer issues.
If you don't like EasyPCB, I use DipTrace.  It was easy and quick to learn for a hobbyist.  Two layer and 300 pins for the free version.  You could have done this PCB yourself in an afternoon.
There is also KiCAD.  It is best to layout your own boards.



--- Quote from: m3vuv on September 01, 2019, 11:20:34 am ---thats not the point,my eagle cad wont run on this pc,thats why im asking,i need this asap plus i need to make a few,should only take a few mins with decent cad software,if it was a one off fair enough.

--- End quote ---

Since you are familiar with the Eagle software and how to layout a board, you KNOW you are NOT providing enough information for people to help you.  The last PCB I tried to help you with, you would NOT even provide sufficient answers to direct questions.  The component sizes/footprints you did finally provide where NOT valid parts.  I am willing to help people but I have LITTLE tolerance for flippant answers and the "run-around".
OM222O:
I'm assuming your "about 5mm" means 0.2" capacitors?
Honestly just have a look:


the first 3 are radial capacitors (i.e: "standard disk ceramic") with 3 different pin pitches!
the next few are SMT caps, again, all with "standard" footrpints. obviously you can't shove a 0201 cap on a 1206 pad or vice versa ...

Also like others mentioned, if you needed a demo, maybe you should have acted faster? giving 3 / 4 days isn't enough for making 100 PCBs ... unless you pay insane costs like others mentioned for DHL express which still takes 2 days!
Renate:
I'm sorry, m3vuv, that this is all a bit frustrating, but some parts of this aren't well thought up.

You're talking about a project where (apparently) most of the parts are off board.
What is this MOSFET that you're feeding? Where is it getting power? Why isn't it on the schematic? Why isn't it on the board too?
Why isn't the pot on the board? What are the physical requirements?

You've got the pot going between VCC and pin 7. When it's turned up all the way, it's a dead short.
The discharge transistor on pin 7 will not like that at all (but might not actually blow up).
You need another resistor in series with the pot to increase minimum resistance.
Not only that, it will keep the maximum tick rate from going through the roof.

You're using an electrolytic capacitor for the timing element?
A garden variety electrolytic cap might be +80/-20% tolerance.
You don't have a lot of range on your pot to adjust for such a variance and still cover your 60-180 BPM.
Also, that capacitor is going to age too.

Especially if you are going to build 100 of these, you really have to consider minimizing off-board connections, hand wiring and getting uniform results out of them all.

It's probably not what you want to hear, but maybe a little microprocessor would be easier to do such that 100 of them all work at the same rate without any calibration.

Another trick that was done in the old days was to run the oscillator at a higher frequency, then use a divider.
This allows you to use smaller, precision capacitors.
Renate:
See my video:
https://imgur.com/a/RYHdFR7
m3vuv:
my throne together setup works well adjusts from a pulse every 8 seconds to 14 seconds and the duration from .5 seconds to 6 seconds,the pots are to fine tune the chemical dose rate,the calcs come at the valve beeing open for one second in every 10.,its for a chemical to break down fat in sewer systems,currently beeing trialed by thames water and mc donnalds,has a huge market potential.
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