Many thanks for helping Tony and his community ! I'm still suspicious on EPROM rather than MCU ... by the way it still worth an MCU change, if available.
Thank you so much! As I suspected, my MCU never toggles pins 30 or 31 low. If I fold pins 30 & 31 out from the socket, it will very intermittently behave like your video. I think this proves that I have a bad MCU. Thanks again!
If you are looking for a better waveform sync, set your trigger function to trigger on a downward slope on the pins that are already HIGH at a idle state, that's what I did and they seemed to lock in well.
Cpu chips do fail and yes the suffix letters or numbers can make a big difference on these type of chips as in speed or built in ram/rom/eprom/nvram. Fortunately we have the net now.
Thanks! I'm kinda skittish about even doing a recap on this one. It has the later model Nichi purple caps, and they seem to hold up well over time, and since its working well, I figure "Don't fool with a Running Piece" , as they say. I did open up, and replace the PA251 DC power brick, might post that as a video, it's only got one cap, a 4700uF - 35V and although it tested great, it is aged so I updated it.
@@pcwrangler09 I also figure that mine might be, since that item is plugged in and probably powered almost all of the units life if set up on a bench, so, yes, was a good thought for you to do that also.
Well done for helping Tony. For my own sanity please indicate which functions, buttons you are selecting to get the signals to toggle (high to low). I am a curious bystander.
Many thanks for helping Tony and his community ! I'm still suspicious on EPROM rather than MCU ... by the way it still worth an MCU change, if available.
Thank you so much! As I suspected, my MCU never toggles pins 30 or 31 low. If I fold pins 30 & 31 out from the socket, it will very intermittently behave like your video. I think this proves that I have a bad MCU. Thanks again!
If you are looking for a better waveform sync, set your trigger function to trigger on a downward slope on the pins that are already HIGH at a idle state, that's what I did and they seemed to lock in well.
Cpu chips do fail and yes the suffix letters or numbers can make a big difference on these type of chips as in speed or built in ram/rom/eprom/nvram. Fortunately we have the net now.
Good Man! Thanks for contributing. I'll need to tackle mine soon.
Thanks! I'm kinda skittish about even doing a recap on this one. It has the later model Nichi purple caps, and they seem to hold up well over time, and since its working well, I figure "Don't fool with a Running Piece" , as they say. I did open up, and replace the PA251 DC power brick, might post that as a video, it's only got one cap, a 4700uF - 35V and although it tested great, it is aged so I updated it.
@@poormanselectronicsbench2021 I agree. If it ain't broke...
The cap in my power brick was out of spec so I replaced it. Helped a lot with ripple.
@@pcwrangler09 I also figure that mine might be, since that item is plugged in and probably powered almost all of the units life if set up on a bench, so, yes, was a good thought for you to do that also.
Cheers.
Well done for helping Tony. For my own sanity please indicate which functions, buttons you are selecting to get the signals to toggle (high to low). I am a curious bystander.
Just what I showed to test the 50pF cap in the beginning of the video, the "Capacitor Value" button.
Dear all, has anyone the schematics of the Sencore IB78 (rs232 interface to Lc102) available for me, thanks ?