Hi Charles,

some comments on the schematic:

- U2 Pin1 is presently unbuffered on P1. Route over U1,Pin17
and 100R instead?

- unused U2:B inputs are at the same voltage (don't know
whether LM393 is a candidate for oscillation but maybe
connect to a different potential?)

- U2 Pin2 could be connected to anode of L1, removing the
need for D2..D4. (Use green LED although red LED probably
has better stability)

- C8 should be exchanged against C7 (U7 should be nearer to
the smaller C, and the (ceramic) 0.1uF is less temperature
critical)

- D1 is probably not needed (but won't hurt either). If you keep
D1 maybe also route R10 and R11 over it.

- JP1 (if you're free to choose the pins I'd _always_ assign
GND to Pin1 and VCC to Pin2

- capacity for the polarized C5 looks a little low and voltage
is not specified, maybe use 25V and a little more uF?

- C7 seems a little large (if someone connects something to JP1
while board is powered up the energy stored in C7 could do
harm)

- the VCC symbol you're using would probably be considered
a GND symbol (in Europe)

- if powerdissipation allows maybe use 78L05 for lower currents
if things go wrong

- maybe add one additional LED to enable blinking or see
TCK activity (maybe use U2B for this?)

- TDO(MISO) doesn't have 100R

- maybe use the (buffered) U2 Pin1 to drive L1?

Greetings,
Frieder