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Oh man, that is cool!  Just what I need another project!  Thanks for sharing, I'm definitely going to check it out.

Yep.  I pulled the trigger on it this week and it is en route from the Netherlands.  Will post again when I get it up and running, unfortunately, which may be some time due to very demanding "real" work and being a single Dad...

This is the one I'm going to build when I find time.  BTW, it has great reviews from the guys that I know who have built it.

http://www.dos4ever.com/uTracer3/uTracer3_pag0.html

Do they  (USA) still charge 20 dollars min for shipping?

I have the usual panavise and others.  Now that the majority of my work is in SMT, I have found the Stickvise to be a great addition:

Well, it shows a trace and has a probe that is a start.  $175 for a 40 year old scope?  Seems a little stiff, new Chinese digital scopes can be had for another 100 bucks.  We have the same scope in the lab, it is never used, the newer 3000 and 4000 Tek DSOs get all of the work.

All of that  being said, probably would be a decent scope for the application, new cheap (not Tek) probes can be had from Amazon or the bay for less than 20 bucks a pair.

I personally use a Tek scope from the 90's, a 2230.  It performs well and as expected for audio / analog purposes and can be had for a similar price and is 20 years newer...

The npn transistor as shown doesn't care if its' base is grounded.  Transistors are current devices, the week pullup (330k) shown in combination with the gain of the transistor turns it on, there is only micro amps of current through the 330k r, if the LED is not fully lit lower the resistance value so the transistor is in saturation.

It's a little unorthodox, but IF it works roll with it.  The only downside is the constant parasitic drain to ground IF powered by a battery.

If it is configured normally as one would using a transistor as a switch, grounding the base is no problem.  The more usual configuration would be to use a pull down resistor to ground after the base current limiting resistor, therefore, when the base loses power the pull down resistor pulls the base to ground turning off the transistor.

Thanks everyone. Just started checking out Tayda and their "easy order" resistor page alone has me convinced I should give them a try when their next coupon code pops up. I won't need 100s of them, but just a couple dozen in each common flavor to do a few projects after I finish my undergrad in May.

That's like the corner dealer giving the kid his first hit.... soon it'll be more and more and then never enough.  Then it'll be more values, different types, different sizes, different power ratings etc, it'll never end - trust me....

Mind your signal phase(s) and ground loops.

Elecrow usually is fairly decent. Here in the states you can get 10 boards for 40 bucks including shipping from Accutrace w/o bottom silk.

Check out http://pcbshopper.com/ for price comparisons between proto houses.

No one says that you can't use a mix of SMT and through hole, especially IF you want to use a film cap in the signal path.  It doesn't matter IF it is a through hole or SMT pcb, proper circuit layout should be observed.  Both could be layed out equally horrid depending on the skills of the person who designed the pcb.

Again, as a guy in my 50's, I applaud your enthusiasm for smd conversion.  Keep us posted!

I'm finding that I am slowly converting to smd for a lot of amp build stuff, albeit a mixed bag of through hole and smt.

John

andy timmons picking one of those clones ... and then the world is hurrying to do so ... :/

Maybe Andy is trying to get his tone back after dumping his Marshall JMPs for Boogie...   

Wow, very prolific indeed.  I like your energy and drive, makes me want to miniaturize things lol.  I'm curious, it appears that you have done a copper pour on the top plane, but left the bottom unpoured.  Is there any reason for this?  In my day job of medical device instrumentation, the PCB guys work very hard at what we call "copper balance".  Besides the "ground plane" effect, as the boards become larger they try to balance the copper on the layers to avoid warping during processing or post processing environmental humidity / temperature changes which can be hell on smt boards with lead free solder.

Regarding reflow ovens, hot air etc, we don't use any in engineering for proto builds or debugging.  All hand placed down to 0402 size under a microscope using Metcal stations - of course the 200+ ball BGAs are usually placed at a board house and x rayed and inductors with bottom pads will get hot air.  To give you an idea of size and density, the last 6 layer board that I did a mechanical check on, approximately 4 in x 4 in, had over 2300 vias and took more than 5 minutes to load the EMN IDF 3D model in Pro-E!