I think I may have damaged two of the steper drivers by being a bit too heavy handed with the screwdriver or i may have accidently touched contacts that I shouldnt have as it was incredibly difficult trying to hold the meter probes and screwdriver at the same time, it did slip a few times off the tuner,
its now not showing any consistent v-reading near .425
I was wondering if the Velleman A4988/SP is the same as a ‘Reprap A4988 Pololu Compatible’ ?
After splashing out on the printer and tools, the difference between £30 for a single Velleman A4988/SP and just a few quid for the alternative is a massive difference, especially if i need to replace 2 
fingers crossed the cheaper ones are compatible until I can afford to get the genuine Velleman’s
For better measuring you can solder some small wires to your probes, and put those wires into the holes in the driver PCB’s
I put a wire with an alligator clip in the negative of the blue connector and connected it to the black lead of my DVM.
After I was done I removed it.
Much easier.
good tips, thanks…
unfortunately bit late… definitely something wrong with 2 of the drivers, one reads 1.4+ and untunable to .425 and the other doesnt show at all…
Absolutely gutted… will be better prepared next time, with a head torch and use the tips suggested as a lot easier than grafting a third hand to myself…
Now I will need to get replacements, so back to the original question…
Are the Velleman A4988/SP the same as a ‘Reprap’ or ‘Stepstick’ A4988 and will the cheaper versions still be compatable?
Turns out they are not the same, very similar but definitely inferior on inspection… I couldnt find a v-ref measure point on the ones i got on the cheap and didnt want to go probing about as I’m pretty new to this… But was only £13 for 4 so not a huge loss and I’m sure I can use them for something (and the included heat sinks) in the future when I’ve read up more on the electronics involved, a fascinating subject…
Ended up buying 4 of the spare part Velleman drivers…
Checked all the motors and switches with the ones I had that did work and looks like when the replacements arrive on Tuesday, I’ll finally be able to start printing 
Well… Got the parts and just printed my 1st test piece and I am amazed… absolutely bang on
Actually the A4988/SP is compatible.
You can use the potentiometer as the test point.
yes I found that out after I bought the originals…
Everythings good now though… Printing well