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Netronics ASCII keyboard and Video Board questions

RizThomas

Experienced Member
Joined
Jan 2, 2012
Messages
198
Location
Surrey,BC,Canada
Apologies for cross-posting. I finally had my hands on this Netronics products ( got it for a fair price few years ago with Explorer/85). After re-soldering ( and IPA+cleaning) all points on the PCB and replacing caps, I got the the Video board working. I also re-did the solders ( and replace the ribbon cable and ic socket) on the ASCII keyboard to get it to work with the Video board. However, I have some puzzling questions about the keyboard. I re-checked all jumper settings according to the manual but...
1. When typing, some keys shows the characters on the screen. However, it sometimes does not. Only when I hit this ?key ( installed by original owner) in combination with the ASCII key that I can make it show up in the screen. There is no explanation ( that I found why so) from any source yet.
2. Repitious characters depending on how fast I hit the key....like I have de-bounce problems.
3. There is area for an extra chip +.. that was not mentioned in the manual nor shown in the schematic.

Anyway... the ?key is on J6 ( normally open) and the unpopulated parts area is near P1 ( ribbon cable)
Would anyone has a tip for me is much appreciated.
Oops... I have to upload my pictures from my computer ( on Ipad right now).


 
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I dug out the keyboard I've used with a Netronics terminal board thinking it was the same keyboard as what you were asking for info on. However, other than using a ribbon cable to the terminal is is completely different. Looking for a description or maker on it and discovered it is a Jameco JE610 ASCII keyboard dated 1979. So sorry, can't help out.
 
Curious … Netronics tended to use Stackpole switches, and I was just the other day trying to find documentation for their ELF II keyboard in the hope of getting the switch series name or part number, but I could not even find assembly instructions (maybe it always came pre-assembled).

From what I can tell, you don’t have Stackpole switches though. Possibly George Risk KBM AKA Futaba MD, from what little I can make out. The weird switch tacked on at the back looks like a European-made Clare high-profile reed (not the same as the Clare-Pendar version made in North America).

And in case it’s still broken: is there a link anywhere to the specific schematics of that model? The debounce time was sometimes controlled by a resistor and capacitor, wired into the encoder. And is the encoder chip the one that the schematics say it should be?
 
RizThomas,
I am working on the same Boards at the moment, but those are somewhat scrapped.
So far missing components are back, But I mis the MK2709 Char ROM.
Do you have an image or BIN,HEX-File of that ROM-U24?
Would be great,

Thanks,
Maurice
20210424_VideoDispayBoard-001.jpg
20210424_Keaboard-001.jpg
 
Sorry for being late..just read my notification just now. I have the chip but needs to find a way to read it. I have to find its equivalent in 27xxx type.
 
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