All information, details and photos supplied by Martin Adams. Martin did a briliant job in converting the original design into a simple to build veroboard version. He also found a neat solution to connecting the Vyper which uses a plug and should also work well with the Cobra.
I am delighted to acknowledge his efforts here! Thanks again Martin!
Component layout (from the top!)
Click on the thumbnail for a larger view, built from three separate close-up images.
Layout from below (showing track cuts!)
If I get the time I will try to reduce this to a diagram - but it looks pretty clear from the photos - just take it steady and check the connections for each component against the circuit diagram.
Martin found a plug which, he tells me, fits well into the Vyper (and presumably Cobra!) socket. His came from a friend who just happened to have an 8 way plug lying around (isn't that always the way!). They cut it into four segments. The pins inside are sockets and with slight manipulation it holds itself snugly on the Vyper pins (being very careful to get the correct way round).
As soon as I identify an exact product code from somewhere like Maplins I will post the info - it certainly makes building the interface much simpler and makes using it faster as well!