RJs Adventures in Mega land III

[rubber_jonnie]

Or a gust of wind

Yeah farting is normally enough ..

Well it would depend on the velocity....

[PhilC]

@rubber_jonnie @exxos I meant farting to fix it. After all, people used to blow into Atari carts to fix them :D

[exxos]

Well it would depend on the velocity....

Things broken = (Fart Velocity x pi) ^2.

[exxos]

I connected up a 3 STFM earlier and they are flaky as hell. They give different faults depending on where you push on the PCB.... 2 hours gone right there fighting iffy boards.. And yet every time I took up a H4 or H5 , it just boots right up no messing!

One of those machines is a test bed for my 4mb ram kits. The larger solder in version.. It begs the question on it being worthwhile even making such stuff anymore if I have to mess for hours just to get the STFM to work to start with :roll:

[rubber_jonnie]

I connected up a 3 STFM earlier and they are flaky as hell. They give different faults depending on where you push on the PCB.... 2 hours gone right there fighting iffy boards.. And yet every time I took up a H4 or H5 , it just boots right up no messing!

One of those machines is a test bed for my 4mb ram kits. The larger solder in version.. It begs the question on it being worthwhile even making such stuff anymore if I have to mess for hours just to get the STFM to work to start with :roll:

All of my STFMs work, what are you doing to the poor things!!

To be fair, I've been saying for a while now that these boards are mechanical failures waiting to happen, so the H4/5 boards make 100% sense.

If there was a Mega PCB replacement on the horizon, I'd be in like a shot, because they seem to be a lot worse than standard STFMs.

[Tomswork]

I agree the mega seem to need alot of servicing to keep them alive bad solder bad caps and not the best ic oh well there still fun to play with and I like the case the best

Tom

[PaulJ]

@rubber_jonnie , not sure I agree.. Have two mega 4's and both are and have been rock solid. Have had a lot of trouble with STFM's as far as reliability is concerned. Sold all but one which I added a blister to and an Exxos 4 meg solder in memory card.. If your mega's were well abused in a past life it takes awhile to get all the damaged components replaced. Its like a referb on a 40 year old car and only changing the parts required to get running. You'll be fighting break downs for a long time. As I recall from earlier posts yours were close to permanent death when you picked them up not to mention a previous owned sawed a ugly hole in the front of one.

Also a plug for Exxos's power supply. It runs my main Mega without issue, runs cool without the fan, and the supply rails look great for a mega... not as good as a H4 or H5 but pretty good. It also always starts even if its been setting for a few months.

[rubber_jonnie]

@rubber_jonnie , not sure I agree.. Have two mega 4's and both are and have been rock solid. Have had a lot of trouble with STFM's as far as reliability is concerned. Sold all but one which I added a blister to and an Exxos 4 meg solder in memory card.. If your mega's were well abused in a past life it takes awhile to get all the damaged components replaced. Its like a referb on a 40 year old car and only changing the parts required to get running. You'll be fighting break downs for a long time. As I recall from earlier posts yours were close to permanent death when you picked them up not to mention a previous owned sawed a ugly hole in the front of one.

Also a plug for Exxos's power supply. It runs my main Mega without issue, runs cool without the fan, and the supply rails look great for a mega... not as good as a H4 or H5 but pretty good. It also always starts even if its been setting for a few months.

It might specifically be that I've just been unlucky with a couple of mine, but my Mega 4 was certainly very easy to break mechanically, and both that one and this one had seen better days. The Mega4 was in a particularly poor state when I got it, this one somewhat better, but somebody had made a bit of a pigs ear of removing the 1772 for a problem with the floppy, meaning quite a few bodge wires for me to do, not to mention, the 1772 was fine, it was the DMA that wasn't.

My other Mega1 is super stable though.

I think in terms of 30+ year old computers, 'handle with care' is something you should do regardless to give them the optimum chance of surviving another 30+ :)

As for the PSU, I actually have a suitable PCB from my Mega 4. I replaced that with a Meanwell RD-50A, which is superb. What I don't have is a PSU frame, as the standard ST PSU frame doesn't fit. I have managed to source one though, so that will get built once the frame arrives.

[rubber_jonnie]

On a side note, one of the plastic 'towers' that the FDD screws come through in the case bottom was basically cracked and broken.

I found that I was able to effect a repair using on of my 3d printed floppy supports epoxied in and cut down to height:

Case_Repair.jpg

Result looks good and seems to be stronger than the original!!

[rubber_jonnie]

Well, looks like I jumped the gun a bit with the RAM expansion. I just realised that sysinfo reports 4MB, but shows only 721KB available once booted. That's consistent with 1MB available, and I think 1MB is what YAART tested.

So the extra RAM is still AWOL, so I think I might have to try dropping in the Marpet expansion I have.

At least the 1MB on board works, which is something.