Reading Schematic Help

Thread Starter


Joined Apr 15, 2009
Hello again
I have recently found a schematic i have been looking for, if you look at this link (because i am not sure how to post pictures)

The parts that say "IC 2, pin 1, IC 4, pin 14" in the top left corner, what does this mean? it appears again in the bottom left does this mean that these pins on this IC have to connect to this specific wire?

Please help if you can Thanks



Joined Apr 20, 2004
The top connections apply the 5 volt Vcc to the CD4049 pin 1 and the 74LS74 pin 14. The lower listing is for ground connections. It's always worth getting data sheets for components so you have full information about their functions and needed connections.

As to posting pics -

How do I attach a file to a post?
To attach a file to your post, you need to be using the main 'New Post' or 'New Thread' page and not 'Quick Reply'. To use the main 'New Post' page, click the 'Post Reply' button in the relevant thread.
On this page, below the message box, you will find a button labelled 'Manage Attachments'. Clicking this button will open a new window for uploading attachments. You can upload an attachment either from your computer or from another URL by using the appropriate box on this page. Alternatively you can click the Attachment Icon to open this page.
To upload a file from your computer, click the 'Browse' button and locate the file. To upload a file from another URL, enter the full URL for the file in the second box on this page. Once you have completed one of the boxes, click 'Upload'.
Once the upload is completed the file name will appear below the input boxes in this window. You can then close the window to return to the new post screen.
What files types can I use? How large can attachments be?
In the attachment window you will find a list of the allowed file types and their maximum sizes. Files that are larger than these sizes will be rejected. There may also be an overall quota limit to the number of attachments you can post to the board.
How do I add an image to a post?
If you have uploaded an image as an attachment, you can click the arrow next to the 'Attachment Icon' and select it from the list. This will be inserted into your post and can be located where you want it displayed.
To include an image that is not uploaded as an attachment and is located on another website, you can do so by copying the full URL to the image, (not the page on which the image is located), and either pressing the 'Insert Image' icon or by typing
after it, ensuring that you do not have any spaces before or after the URL of the image. You can insert pictures from your albums (?) in this way too.
I think you are correct in thinking that the wires need to be connected to those specific chips and pins. Those are the power and ground connections for the ICs in this setup.

The top connection is +5V. IC5 is a voltage regulator whose output is 5V. The connections on the bottom are ground.

Thread Starter


Joined Apr 15, 2009
thank you
i thought it was pretty straight forward, it says this pin here so it goes here, simple, and thanks for helping me with the attachment thing, im gonna test it now anyway but thanks, One more quuestion, i am currently using the program Crocodile Pysics 601 to build my circuits to see if they work, and then if they do i etch the PCB, however for this circuit and some others there are IR transmittera and receivers involved and Crocodile Pys dosen't do this. Does anyone know of a program that does?
Or can i update Croc Phy?

Thanks, Chris



Joined Jul 17, 2007
Cadsoft Eagle has been pretty popular with hobbyists; they have a freeware version that's limited in the size of board it'll make (3"x4") and just two layers - but enough for many hobbyist needs.

There are more available; see our Electronic Resources forum.