ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi all,
After sorting the datalink issue with my BG7000 (thanks to Martin ) I've turned my attention to the BG6500 that I acquired at the end of last year.
It came with a full 6500 system including MCP and original paperwork - beautiful condition and one owner from new, an elderly gent.
When I collected it he told me that the BG wasn't working but didn't know the problem. He hadn't used it for years and he's recently moved house so thought it may be to do with the transportation of it?
I got it home and set up the system, everything working (apart from needing new belts on the beocord) with the exception of the BG.
I checked the fuse and it's fine so I checked the transformer and I'm getting a steady 11.8V out of the power supply PCB.
Can anyone offer any help as to where to start looking for the problem?
Any help appreciated!
OK I've taken some measurements and getting these readings at the pins of IC1
Pin 2 - 2.13V
Pin 3 - 1.95V
Pin 9 - 7.97V
Pin 14 - 3.81V
Pin 16 - 0.97V
Pin 17 - 0.24V
Pin 18 - 0.24V
Does this shed any light?
When the front panel play button is pressed the reading at pin 14 drops from 3.8V to 0
Also when the keyboard buttons are pressed their respective pins (5, 6, 7, 8, 10 & 11) measure at 3.7V
IC1 pin 9 should be 5V.And due to zener D2 not more than 5.1VThat's the supply to the IC.
Check D2 and TR1 (and TR2 while you're at it).
Martin
Well I ended up going the easy route and getting a beyond-salvage donor deck and swapped over the main PCB.
As if like magic all back to life again!