FRG7700 Memory Expansion Tips.         All photos copyright John Mills, except where noted, last updated 17 April 2011 The FRG7700 still appears for sale regularily on auction sites and is still very popular. Many are fitted with a 12 channel memory unit. As explained in an article I wrote for Radio & Electronics World magazine in June 1983, the memory unit is acually capable of storing 256 frequencies. The article is available to download as a PDF by clicking here, please note however that the SRS303U switch used in this article has LONG since dissapeared, so please DO NOT contact me for sources of supply. If you have any old CB radios around then it is likely they will have similar switches in them, but again I am unable to help on these as well. The article should however allow you to gain enough info to allow you to fit a couple of switches to the back to expand the memories to 24 or 36. The memory chip datasheet is here. You are on your own here, but I hope the article will provide some ideas to work to. Photo copyright of SV1XB