exxos's Atari, Amiga & retro forum

:dualthumbup:

So, I like to power on my machines regularly to be sure everything runs fine, and I usually leave them running during the day as I work from home and my office and retro area are the same room.

And boy has the Apple ][e been a bit unreliable, with the RAM/80 column card 'disappearing' and random floppy unreliability. The only thing that seems to have been unaffected is the Mockingboard sound card.

It seems fixed now, basically the edge connectors of the RAM/80 column card and home built (Not by me, that's how it came) FDD controller needed to be cleaned and seem to suffer from oxidisation despite being gold plated.

I've also noticed whilst doing this that when the machine starts from cold the display is shimmery, but once warm it really does stabilise quite a bit, so I'm thinking I might have a look at the caps in the video circuit, see if replacements might make it look sharper when cold.


EDIT: Just a short time later and the RAM/80 column card has vanished again Merdé!!!

Are the sockets getting loose in their old age?

I'd spray Electrolube EML down there and wide the contacts with folded paper to polish them. :-)

I take it that you've checked the +5V rail for ripple with your 'scope?

What Mr Usher says and have a good look at the ram card socket itself. If you are careful you can retension any wayward pins but it does sound like you have a power supply issue of some description as well.

My Apple //e is actually one of my more reliable machines believe it or not.

rubber_jonnie wrote: 20 Mar 2023 16:31 Merdé!!!

I guess you wanted to say "Merde !!!"...

;)

stephen_usher wrote: 20 Mar 2023 19:50 Are the sockets getting loose in their old age?

I'd spray Electrolube EML down there and wide the contacts with folded paper to polish them. :-)

I take it that you've checked the +5V rail for ripple with your 'scope?

I did hit the sockets up with Electrolube as it goes but it seemed to make little to no difference. I also cleaned the contacts with IPA on the cards. However, on powering down from an instance where the RAM card was not picked up and leaving it to cool off, the problem went away

As for cleaning and tweaking the sockets, yes I will do that when I have some more time, hopefully at the weekend. I haven't checked for ripple yet either, though the RIFAs have been replaced, but not any of the other caps.

The joys of being a retro computer owner :)

PhilC wrote: 20 Mar 2023 22:23 What Mr Usher says and have a good look at the ram card socket itself. If you are careful you can retension any wayward pins but it does sound like you have a power supply issue of some description as well.

My Apple //e is actually one of my more reliable machines believe it or not.

I may try running it with no RAM card for a bit and see if it makes a difference, but I will have a closer look at the socket, see what I can see.

I wouldn't be surprised if the PSU is in need of a service.

HigashiJun wrote: 21 Mar 2023 03:26

rubber_jonnie wrote: 20 Mar 2023 16:31 Merdé!!!

I guess you wanted to say "Merde !!!"...

;)

Who doesn't :)

:roll:

Ok, had a quick 5 minutes to test the AC ripple on the 5v line and it's 36-40mV peak to peak. From what I can see, that isn't too bad.

However I'm now getting some other weirdness. With the colour killer set to off, I get no video out, but you can see from the floppy emu that it is booting.

If I set the CK switch to on, I get monochrome video back. If I switch the CK switch back off whilst running, I get a colour display.

If I then reboot with the CK switch off, I get no display. Very strange.

So, I'm going to go find the schematics and have a look see.