Build Instructions and tips

[Will Senn]

If someone decides to write up a set of instructions for building the PAL-1, or if somebody happens along to this thread, here are some observations related to building:

0. Rush out and buy a power supply 7 volt, 1+ amp. You'll need it right after you finish the solder work :).

1. Refer to the interactive BOM to see what goes where and keep track of your work:

http://pal.aibs.ws/assets/ibom/pal-1.html

2. Solder in a rational order (if there's a smarter way, let me know. I didn't do it this way, and I suffered)

Start with resistors, capacitors and diodes (low profile components)

Then do resistor network, electrolytic capacitors, led, crystal, and sockets

Then do pushbuttons, and sst switch

Then do io pins and jumper pins

Then 7-segments

Then the power socket and rs232

Basically, start with the shortest components and work your way progressively taller. Otherwise, you'll wind up needing a third hand to help you hold components in place while you solder on the backside.

3. Once you finish soldering, attach power and see if anything smokes and that the power led lights up.

4. Watch the direction of the sockets when installing the chips (6502 and 6532 are different from the other horizontal chips).

5. Remember to check for solder bridges (I didn't have any, but you never know).

I'm curious what other tips folks might have. Maybe this thread would be a good place to put them.

Regards,

Will

[Magnus Olsson]

I built mine in almost the same order, but with a few differences: 

I put in the power regulator and power jack at quite an early stage (after the passive components) so I could do an early smoke test. 

I also put in the crystal oscillator last, because it's really a hybrid integrated circuit and not just a passive crystal, and I wanted to expose it as little as possible to the risk of ESD. Also, I did some more smoke tests and power distribution tests (+5 V appearing on the Vcc pins of the IC sockets, for example) and didn't want to have the oscillator connected during those.

[Will Senn]

I like your approach, nice.

[Jim McClanahan]

One thing I always do is clean the flux off the board that is there from the solder "tinning" they do to the board. Generally that makes soldering go faster and reduces the chances of a cold solder joint. I use a little "brush" that has strands of glass. I got it from Radio Shack years ago and it is the fastest approach. The solder pads will be noticeably brighter once they are cleaned.

The other thing I recommend to anyone doing much tinkering is to invest in a variable power supply with adjustable current limiting and a ammeter. They have come way down in price these days and can save a lot of hassle if you accidentally get something wrong.

A pure cosmetic thing I'll do next time around is use a black sharpie on the sides of the LEDs that butt up against each other. I didn't do this but have on other projects and it looks a little neater if you don't see the white where the LEDs touch.

Thanks,

Jim W4JBM