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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Ya, I think you have to keep it refrigerated too. Like I was saying though, for just one SMT part I probably won't use a stencil, which is why I was looking at making a dispenser, but we'll see how it goes.


In other news, I sourced new 1uf caps that are non polarized, but I'm probably going to switch back, because the footprints are actually larger:

I would just try to solder SOT23-5 with an iron and (good quality) solder wire. Start with the side that only has 2 pins, which should be fairly easy.

Get some desoldering braid to fix any bridges.

Edit: reacted too quickly. I see that you've already tried this method. Maybe dispensing paste would work better then.

Still, good quality solder makes a huge difference. My favourite kind is Multicore C511 (leaded).

I may have to get some better solder, I have some that's from radio shack that's really old, and some that I got on amazon, I think some of it is silver bearing, and some is leaded, I can't remember.

In other news, I think I've got my clock generation circuit all laid out, I realized I had the wrong footprint assigned to the rheostat, which ended up saving me a bunch of space, here it is:

The SOT pads still look a bit small. I would make them twice as long. You have plenty of room.

Don't make them wider, because you want to keep as much gap as possible, just sticking out further.

Also, if you're looking for solder wire, get some thin stuff. That makes it much easier to control how much you feed in.

In case you want to see better, forget the desk magnifier lamps. Instead, get a cheap pair of reading glasses with highest strength you can find (usually +3 or +3.5)

I have a 3rd hand with a magnifier, but it's a huge piece of ****, always falls over. I will say the magnifier has helped bofore (when pulling a MEGA2560 off a board and putting it on another).

I just used the footprint that was in the libraries for kicad, I'll see about lengthening the pads to help with soldering

As far as wire, the stuff I have is very thin, I'm just not exactly sure what's in it, I'll have to check it. I do have solder wick though, (and a solder sucker, which is completely useless for most things), and the hot air kit I have is actually pretty decent, even being a china direct sort of thing.

I'm still considering paste though, just because I want to get some time with it, and learn a bit about it. My biggest fear is that this chip will be exactly like some smd caps I've done before, that it just gets sucked up onto the tip of the iron.

Actually, I've used mine with good success on small SMD parts, like TSSOP and TQFP with 0.5 mm pitch, especially with bridges deep under pins where the solder braid can't reach. In that case, I put a big blob of solder on a dozen pins, heat it all up, and suck it up with solder sucker.

I have one like this:
http://www.edsyn.com/product/DS017.html

I have one almost exactly like that. I'll say, I've not experienced a bridge yet that's gone underneath the chip, because I've been very careful not to get to that point since I've heard they're hell to get rid of. When I tried using my solder sucker it tended to make more bridges than it got rid of, but maybe I just had it at the wrong angle. I also tried using it on some boards with big power connections and it could never get enough solder off to actually remove cables (heat beds for 3D printers have cables directly soldered to them). Ofc, I don't think this is necessarily what it was designed to do.

Magnifier:

I have one of these: https://www.amazon.co.uk/Illuminated-Ma ... B01M2442NR

Well, not that exact model but one very similar. The one I have while cheaper still allows for 2 magnifiers that I can flip up/down. The LED light is fairly crap though.

And on solder suckers - I've used them for .. forever. Like it a lot. Never really had issues using it, but I don't do a lot of SMT work, but the sucker and braid are fine for me. I have the usual spring-loaded pump type. The nozzle wears out every few years though - maybe I use it too much!

However I did play with an electric heated motorised pump one recently and loved it, so might buy one myself - EEVBlog Dave raved on about one a while back in his usual manner too.

Cheers,

-Gordon

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--
Gordon Henderson.
See my Ruby 6502 and 65816 SBC projects here: https://projects.drogon.net/ruby/

The way I do SMD stuff like capacitors and resistors, I put a blob of solder on one of the pads, melt the component into the solder(holding it in place with tweezers), let it cool, and then solder the other side as normal.
SOT devices are trickier, at least for me, because I have a relatively big conical tip on my (unregulated) soldering iron. I spent a while getting on four of the black bugs, and then had to remove one(the one in my EEPROM write-protection circuit) because I'd ordered the wrong part. I then ordered what I thought was the right part, but I;d actually ordered a smaller part. I bent the pins outward a bit, and got it on anyway, but that one was with a regulated iron at my uni, with a nice small tip.
Regardless, I go over the pins of an SMD with a continuity tester to make sure there are no unwanted shorts.

Also, as regards board houses, I went with DirtyPCBs, and got what I consider a bargain. US$45 got me 10 100x100mm 4-layer PCBs. Quite cheap, as I understand. You just have to do due diligence on your board designs, because they do absolutely no checking. What you order is what you get.

It's been brought to my attention in the thread I started on a variable clock that the 6900 takes 75us to settle to a new frequency, the 1799, which is an upgraded version, takes only 25us, but still very slow.

As long as the clock is clean during this time, it only means I'd have to delay talking to slower devices if switching downward to do so, for at least 25us.

This is making me reconsider the 525 chip, since I don't think it has this problem.

From what I've gathered in the other thread, it seems like the 525 will probably have a similar issue to the LTC1600 or 1799, and probably many of the other chips out there will too. I'm going to do some more research on using PLLs, because I think that if there's an answer to this it involves PLLs. I swear this is driving me insane, most of the other issues so far aren't that far out of reach, this one, as simple of an issue as it seems to be, seems impossible to solve correctly.

As I said in the other thread, I may have to just switch to using wait states and (begrudgingly) buy a bunch of oscillator cans

What if you use a manual VFO, like Garth mentions in his primer, test it, and then put in a fixed-speed can once you determine the maximum frequency?

I mentioned doing something like this in the other thread. This is not the most ideal situation for what I'd like to do, but it will work, but I will need to include wait states to access slower things like EEPROM

If that's an RS232 level shifter IC then please note that the MAX202, ST202, or MAX232A transceivers are the same as a MAX232 transceiver but they can use 0.1-uf monolithic ceramic caps... You could install them under the IC in the open area of the machined pin IC socket...