de WB2CPN I have had both, and still have the 751A. It's my understanding that except for the front panel layout they are almost a different radio. If you lay both block diagrams, (or schematic), side by side you'll see what I mean. The 751A is noteable for being one of the best CW and RTTY radios ever. They can withstand a lot of mistreatment. 73 Clete