Sourcing and measuring J201 JFETs for a Chop Shop

ragamuffin

Well-known member
So I'm wanting to build a Chop Shop. I've read that it can be picky about it's J201 JFETs, and read in another thread that ideally you want Q1 to have an Idss in the 600-800 uA range and Q2 an Idss around 400-600uA. I have not worked with JFETs before, but I assume this means that I should buy more than two in order to find to find suitable values.

Where's a good source for some J201s? Looking at my usual sources, Tayda and Small Bear seem to be sold out, they're $5 a piece at Mouser or Amplified Parts, but on ebay I see listings of ten or so for around $15; can I trust the ones on ebay? And then theres surface mount options, but I've never worked with surface mount parts and I fear that my non-adjustable 35 watt soldering iron may be too hot for them.

Also: testing? I've seen that RG Keen has a JFET testing article, anything else I should be looking at?
 
The Keen method works really well, SMD will be a bit of a challenge, but doable. The pedal is great, worth the effort.

Get some liquid flux (the type that comes in a pen is ideal for this) and put that on the circuit board pads before you place the SMT. Put a small dab of solder on your iron tip, hold the SMD down with a toothpick, and barely touch the pad/transisor with the solder blob on the tip, basically, the solder jumps from the tip to the fluxed areas. It ends up being really easy.
 
MMBFJ201 (SMD version) JFETs are readily available from big box suppliers: mouser, digikey, farnell, etc. and basically are guaranteed, low to no risk.

With very few exceptions, eBay or Amazon for any parts is a gamble not worth taking. I mean, unless you want cheap-@$$ stuff for breadboarding.
 
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