Memory modifications on a NDH-515.

Simple version with only one extra front-hole for a 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 positions, now 8 x 24 channels display, with the same original memory chips.



Click on pictures to enlarge


   Jump back to the NRD-515 webpage for all the hardware info
  © 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 photo part of the NRD-515 page




mem515.htm
by Walter - PE1ABR - 2020-07-30