v2 Analog - Apple ][ VGA adapter build

[PhilC]

@rubber_jonnie they look actually pretty reasonable to solder considering the size of some of the components

[rubber_jonnie]

@rubber_jonnie they look actually pretty reasonable to solder considering the size of some of the components

I was thinking much the same Lots of space to move around in.

Isn't it about time you changed your avatar to a non xmas one

[PhilC]

@rubber_jonnie it certainly is but I can’t find the normal one at the mo

[rubber_jonnie]

@rubber_jonnie it certainly is but I can’t find the normal one at the mo

BTW here is a non soldered test of a couple of bits

PXL_20230403_121922779.jpg (226.79 KiB) Viewed 1267 times

And they plug into the expansion sockets perfectly.

One issue I am having in advance is programming the PALCE 16V8H IC. I have some GAL16V8 ICS that work fine with my TL866II Pro, and the PALs are supposedly functionally identical, but can I program them. Nope

At the moment it seems like soldering tiny components is the least of my issues if I can't program the PAL.

[stephen_usher]

Wires from the pads onto the legs of a GAL and glue it as a dead bug on the board?

[rubber_jonnie]

Wires from the pads onto the legs of a GAL and glue it as a dead bug on the board?

My GALS are actually 20 pin PLCCs like the PAL chips, so it should be a direct fit, I'm just worried the GAL will perform as well as the specified PAL.

I haven't had time to figure out if this will be an issue.

[rubber_jonnie]

Ok, so just waiting on one lot of parts, some SMD caps, so hopefully I can begin the build over the easter weekend.

Given the component sizes, it's going to be interesting getting it done, but I at least have a microscope, so that should make things easier. I have lots of spare components too, fingers crossed I won't sneeze them all into oblivion!

[stephen_usher]

[rubber_jonnie]

So, no sneezing, though I did manage to lose some components, though at 1mm x 0.5mm I think anybody could be excused for losing one or two!!! Luckily I had bought extra so no issues with not having enaough.

Progress today was good once I figured out the technique I needed to make it work. A microscope was a definite necessity.

The technique was quite simple in the end and was simply put some flux down, tin one of the pads for the super tiny component, then drop the component onto the PCB, locate it and using super fine tweezers, and locate it next to the pad.

All I then did was heat the solder on the pad and move the part into position to solder one end. There was enough residual flux to make this work just fine.

Once all the similar components were in place I then fluxed the other end and went round each component with a tinned iron (I was using a K bit to leverage the high thermal mass with fine tip) and holding the component with tweezers, just touch the other end quickly to form a joint.

I have to say it worked really well, but a decent flux, in my case Kingbo RMA-218, really did help out, especially with the ICs when I needed to drag solder. Overall the reults look good:

PXL_20230407_151532664.jpg (251.28 KiB) Viewed 1158 times

And all the parts check out ok with my multimeter showing continuity and correct values all along the way, and no shorts on the IC legs.

Just waiting on a capacitor before I can solder on the PAL/GAL and I need to add on the Rpi too, but I'm leaving the large parts until the rest of the small ones are done.

[rubber_jonnie]

Well, I'm happy to say the v2 Analog is now built Even better it looks very much like the pictures here: v2 Analog website

PXL_20230413_080444401.jpg (300.22 KiB) Viewed 1117 times

Having just soldered on the GAL and the Pi Pico, which were both programmed before installing, I need to double check all their connections to ensure they have no shorts, but once that's done I'll be able to plug in and see if all my micro soldering worked!!!

From a soldering perspective, this is the hardest hand soldering I've done, and thank god for having a microscope!

Got to do the work thing now, so it'll have to be later.

Although my Apple IIe has a fault with the RAM/80 column card, it still works fine as a stock machine, so I should be able to test it later on too