SHIELD SYMBOL? 1

[frankreid]

I have been working on some electronic schematic diagrams and have had to redraw some symbols. One of them I've never seen. It appears to be a shield symbol but I have always used a different type. It appears as a circle with a baseline on the bottom but sometimes on the top or sides. I've looked at electronic symbols on the internet but can't find anything like this. See Sample.

Do you know what this is? Any help will be appreciated.
ps: I was unable to upload a picture, the My Documents list is not what's on my computer???

Frank Reid
Reid Engineering Services of Utah
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You'll never know what you are worth until you learn to say NO.

 

[chicopee]

draw a sketch;scan the sketch and send it as a JPEG attachment.

 

[dik]

The 'shields' generally represent logic symbols...

A shield with a 'flat' top is generally used for a Boolean 'AND', a shield with a 'concave' top is generally used for 'OR'. If a 'little circle' is at the bottom of these 'shields', then the symbol is for a 'NAND' and 'NOR' respectively.

Dik

 

[chicopee]

Since DIK mentioned logic diagrams, I have a JPEG attachment showing a table of different logic symbols from a 1978 Machine design article. One of the symbols matches your description.

 

[dik]

Your NAND and NOR symbols look like I remember they should...
thanks, Dik