Hi chaps i have a Linn LK1 preamp that is lighting up like a Christmas tree and bugger all music coming out
I have changed majority of the caps on the control boardstill the same
I was going to change a couple of the ICs next and got them on order from ebay
There is a mk3 labled eprom that would be the next thing to change
I was wondering if anyone had the eprom programing data for this chip if I needed a new one
I'm not into electronics but really enjoying this challenge
Any advice would be appreciated
Thanks
Gary
I have changed majority of the caps on the control boardstill the same
I was going to change a couple of the ICs next and got them on order from ebay
There is a mk3 labled eprom that would be the next thing to change
I was wondering if anyone had the eprom programing data for this chip if I needed a new one
I'm not into electronics but really enjoying this challenge
Any advice would be appreciated
Thanks
Gary
I doubt there is anything wrong with the eprom.
99.9% it’s faulty leds.
Go round them with a suitable current source and change any dim ones.
99.9% it’s faulty leds.
Go round them with a suitable current source and change any dim ones.
That's strange, why would it light up like a Christmas tree and produce no sound if the LEDs are faulty?
The leds form part of the keyboard matrix. Faulty leds confuse the processor into thinking someone is hammering on the keyboard.
OK, that's a good first thing to try then.
Regarding the EPROM, you could try reading it at a slightly too low supply voltage and at low speed, and then copy the data into a new EPROM.
I know they used to verify EPROMs at a somewhat higher than normal supply voltage, so apparently higher voltages make it more difficult for the EPROM to read a programmed bit (0) properly when there isn't as much charge on the floating gate as there should be. Conversely, lower voltages should help it to read these bits properly, or so I hope.
Regarding the EPROM, you could try reading it at a slightly too low supply voltage and at low speed, and then copy the data into a new EPROM.
I know they used to verify EPROMs at a somewhat higher than normal supply voltage, so apparently higher voltages make it more difficult for the EPROM to read a programmed bit (0) properly when there isn't as much charge on the floating gate as there should be. Conversely, lower voltages should help it to read these bits properly, or so I hope.