Sounds good...As per the logic probe. IC5 pin 11 receives a pulse ( red and green leds on my LP1 logic probe.)I'm by no means an electronic expert... but an Oscilloscope would be of better help here to check the pulse(s). If it was me I eventually would cut some traces with a thin blade (and only a small cut so one can place a small 'solder blob' to reconnect the disruption later) to check if and where the pulses are 'getting back to normal'. Maybe the issue can be found this way...?So i replaced the original ic (74LS74) with 74HC74. But the issue is same. I don't know whether the replaced IC is not compatible, the replaced IC is already blown or the is in somewhere else.
Please help. Thank you.
Oh, by the way: please check if the PD voltage coming from the PSU is ca. +5V (against ground). You can measure it at C5/Pin8 (white wire) of the PSU.
Hi Miks,
I got my self a logic analyzer scanned the sub cpu (IC13)
I was able to see a good square wave signal at pin no 4( XTAL) and however, the 5th pin (EXTAL) is always high.
Does this mean that the crystal is faulty?
Thank you for your time.
Statistics: Posted by Janku97 — Mon Jun 17, 2024 9:08 am