Post Reply 
HP-65 card reader problems
02-16-2020, 10:16 AM
Post: #12
RE: HP-65 card reader problems
(02-16-2020 08:22 AM)coitboy2000 Wrote:  Ok great

So what controls the voltage sent to the motor when a card is sensed ? That appears to be the issue.

Cheers

When the card is detected in the slot by the CRC on the CPU board, it then sends a Logic LO signal to pin #17 of the sense chip which then outputs the motor drive voltage from pin #1. Some of this voltage is fed back to pin#2 through the 4K64 resistor to regulate the motor speed.

cheers

Tony
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
HP-65 card reader problems - coitboy2000 - 02-02-2020, 01:59 AM
RE: HP-65 card reader problems - teenix - 02-02-2020, 06:03 AM
RE: HP-65 card reader problems - teenix - 02-02-2020, 09:44 AM
RE: HP-65 card reader problems - teenix - 02-02-2020, 11:38 AM
RE: HP-65 card reader problems - teenix - 02-04-2020, 02:46 PM
RE: HP-65 card reader problems - teenix - 02-16-2020, 07:14 AM
RE: HP-65 card reader problems - teenix - 02-16-2020 10:16 AM
RE: HP-65 card reader problems - teenix - 02-16-2020, 10:33 AM
RE: HP-65 card reader problems - AndiGer - 02-16-2020, 11:09 AM
RE: HP-65 card reader problems - teenix - 02-16-2020, 11:42 AM
RE: HP-65 card reader problems - AndiGer - 02-23-2020, 06:47 PM
RE: HP-65 card reader problems - teenix - 02-23-2020, 09:19 PM



User(s) browsing this thread: 2 Guest(s)