Memory modifications on a NDH-515.

Simple version with only one extra bankswitch ( board )   + two GAL's (new kind of PROM) for BCD to BIN memory control and back from BIN to BCD for display.
Original 1 x 24, now 8 x 24 channels display, with the same original memory chips.



Click on pictures to enlarge
  © PROJECT ENGINEER:
WALTER - PE1ABR.




mempeter.jpg
Peter's memory_1
mempeter.jpg
Peter's memory_2
mempeter.jpg
Peter's memory_3
mempeter.jpg
Peter's memory_4
mempeter.jpg
Peter's memory_5
mempeter.jpg
Peter's memory_6
mempeter.jpg
Peter's memory_7
mempeter.jpg
Peter's memory_8
 
Original first HTML code: C.L. van Soelen - PG9HF


   Back to previous page




mem515.htm
by Walter - PE1ABR - 2013-03-18