I have a Sansui AU-9500 with a hole burned through the F-2029 driver board. I was able to bridge the traces and get it working but it always bothered me so, when I had a chance, I had some new boards made. The new boards are like the original except modern transistors and diodes have been substituted to replace the originals. Also an option to use the original TO66 drivers, which can still be found for about $8 each or TO220 substitutes of which there are several. KSA940 and KSC2073 have nearly identical specs at about $.30 ea. They work perfectly. Of course I have extras on Barter Town if anyone has the same problem.