Nets are not copied when copying and pasting in Ultiboard because the action is not well defined and causes confusion. If you think about it, when you select objects in Ultiboard, they are usually components, you can select traces, but you cannot select nets. If Ultiboard were to copy nets, would you expect it to copy only nets internal to the selection? For example, if you were copying and pasting an active filter, you would expect that the pasted circuit contained the correct connections that made up the filter. What about nets connecting your selection to the outside? For example, you where copying and pasting digital components, you would expect their power pins to connect to the board power rails. How would you control exactly how your pasted selection is going to be wired up if you wanted a combination of the above behaviour? What should the new net names be? These are really tricky questions to answer because everyone has different opinions and what behaviour you want depends on what you want to do.
Instead copying and pasting in Ultiboard, it is much more convenient to do this in Multisim. It is an even better design strategy to place these components in subcircuits and copy and paste subcircuits. When you are ready, forward annotate to Ultiboard. This is the recommended work flow. When you want to duplicate your placement and route, use Design>>Group Replica Place and Design>>Copy Route. It is a much more elegant solution to your problem.
Hope that helped.
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Yi
Software Developer
National Instruments - Electronics Workbench Group
