Hi SAM, I affraid that it will be hard to use my solderpaste dispenser for the SOT-883L, it has very small dots.

Even so, I'm looking forward to trying it :)

Hi Sam, is it possible to use still VMT-3 transistors, with a track size of 4mil and hole size of 0.2mm? Such a PCB costs about $50.

That could be feasible, I'll give it a try when I have some free time :) I'll attempt both EMSL version 1 and EMSL version 3 (with two extra schottky diodes).

Hi Sam, 
I understand, I didn't know that making HDI PCB was so expensive at pcbway. So I let you use the SOT-883L.

Yes, with the SOT-883L it is easy. But the challenge is to use SMD parts with outstanding pins, not ball grid like pins on the bottom (sorry). You can look here for an example of a high-density PCB:

https://www.avdweb.nl/tech-tips/pcb/pcb-manufacturing
I Think you need very small trace widts (0,1mm) and vias.

I wouldn't call it "easy" with the SOT-883L, but okay...clearly you and I have different definitions of "ball grid," haha. PCBway wants $160 USD for 0.1mm trace width/clearance and 0.15mm vias, best of luck finding someone to take you up on that offer.

Aisler made me a 4-layer board with a few 0.15mm traces (their design rules go down to 0.1) for just about 24€ for three boards. Min. via size is 0.2mm though!

Ahhhhhh, thanks @Xasin ! I can't believe I forgot about Aisler, I've only been out of Germany for a few months but they already slipped my mind D: D:

I have to do some re-arranging to account for their 0.3mm edge clearance rule, but I hope that won't be too bad.

Following up: Did you know the EMSL kit is now on Revision 3? The PDF you link to here is Revision 1. Revision 3 is here: https://cdn.evilmadscientist.com/KitInstrux/741/741_datasheet_rev20c.pdf

The latest version adds two Schottky diodes into the circuit. It took me a couple tries to route it on two layers, but I'm optimistic that it will work! Will keep you posted.

I stumbled across this while looking for a solder paste dispenser such as yours. This is a very good challenge, it is exactly my kind of humor!

Did you try routing your design with the VMT-3 transistors? I found that they were still too large. With SOT-883L transistors (1mm by 0.6mm) I was just *barely* able to route everything on a 2-layer PCB. After I do a few more sanity checks, I think I will order some and I'll let you know if it works. My current design files are here, if anyone else wants to give it a try: https://github.com/settinger/discrete741

Now I want to try this with the 555 timer, too! But that has 6 additional transistors--I may have to make it double-sided and four-layered, we'll see :)