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Old 21st Oct 2018, 5:32 pm   #101
Slothie
Octode
 
Join Date: Apr 2018
Location: Newbury, Berkshire, UK.
Posts: 1,287
Default Re: MK14 schematic revisions

Great news! I finally tracked down all the wiring errors on the pcb. I've typed in the program SiriusH gave me and got "Slothie" on the display as a reward, so all would appear to be working as expected. The only odd thing is that on reset 8 out of ten times you get random digits on the display in the gaps between '0000' and '00' - but pressing Abort clears this and all seems to operate as normal. If I ever find my scope and probes maybe I should look into the reset timings.
I tried to get a photo of the output of SiriusH's program but its a bit hard to see - maybe I need better lighting. However if you squint a bit you can see it. The random looking wire at the back is grounding the "SENSE-A" pin so that programs will run...
The other photo shows the modification wires on the bottom.... lets just say I think I will get a new PCB made, if only because the wires are going to be a pain snagging and breaking etc. I also need to put some diodes or a resistor in the power lead because the regulator runs HOT (hot enough to make you not want to touch it - I measured it as 60 deg C and stil slowly climbing.) When I redo the pcb I might make room for a bigger heatsink or fab one from aluminium,
Well, thanks to everyone who offered help & encouragement, as I am now in posession of a working MK14! All I need to do now is to write a few programs for it...!

Slothie
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