TNC2C - SOME PROBLEMS AND CURES

TNC2C HAS BEEN MADE IN SEVERAL OPTIONS, THERE ARE A FEW GERMAN VERSIONS,
TNC2C (TNC2C-DL) AND TNC2S
I HAVE SEEN DANISH VERSION (TNC2C-OZ) AND A SWEDISH VERSION (I CALL IT
TNC2C-SM) HAS BEEN DESIGNED.
A VAST INTEREST HAS BEEN SHOWN FOR THE DANISH VERSION, AND SINCE I HAVE ONLY
STUDIED THE SWEDISH CIRCUIT DIAGRAM, IT SEEMS THAT THE DANISH VERSION IS AT
LEAST ONE OF THE BEST, THE DANISH VERSION IS IMPROVED ON SEVERAL POINTS
COMPARED TO THE GERMAN VERSION. THE DANISH VERSION USES SOME EASIER TO COME
BY COMPONENTS. I HAVE BUILT BOTH THE DANISH AND THE GERMAN TYPE.TNC2C(DL).
THE NOTES REFERS TO THE CIRCUIT DIAGRAM FOR THE DANISH, HOWEVER I BELIEVE
THE COMPONENT DESIGNATIONS ARE THE SAME FOR THE GERMAN VERSION TNC2C.
WHICH I BOUGHT FROM NORDLINK.
1) IN A FEW UNITS THE EPROMS HAS BEEN TOO SLOW, BUT ORIGINAL MFJ1270B SOFTWARE
WORKED PERFECT.
2) THE DANISH VERSION USES XTAL 4.9152MHZ, AND MARKINGS ON BOARD IS FOR THIS
XTAL. TRANSMISSION SPEED IS NEVER A PROBLEM HERE, WORSE IS TO REACH NEXT STN
SO IT SAVES SOME