bfollowell

Well, that's the point. You can't connect a 220VAC item to 120VAC supply unless you wish to damage the item that you're plugging in. That's just not a very smart thing to do. Sometimes, nothing much will happen other than the item won't work. Oftentimes, you risk serious damage to the item you're plugging in. I get what you're saying though, and I think I missed it the first time through. You plugged the 220VAC U.K. PSU into 120VAC U.S. and expected to see some smaller VDC output, but were surprised that you still had 5VDC and 12VDC output. First of all, where did you buy this machine? Where did it come from? My U.K. machine came directly to me from the U.K. from the person I purchased it from. Everything about it was factory U.K. before I stared converting it. If you got your U.K. machine from someone in the U.S., then I would think there's every reason to believe that they had already swapped the PSU to a U.S. type. Otherwise, they wouldn't have been able to use it. If your STE came to you from the U.K., I can't think of any reason that anyone there would have switched to a U.S. style PSU, because then they wouldn't have been able to easily use it there. Also, if it is in fact a U.S. PSU, it is all more likely that they swapped out the U.K PSU for a U.S. PSU. The circuits would've been different, more than just a few different value components. It's extremely doubtful that someone would've converted the PSU itself. If it was converted, then it is almost certain that they converted the machine by swapping the PSU, not converting the PSU itself. First of all, have you been able to successfully boot this machine at all? Secondly, please humor me, post a picture of the bottom case label from your machine and another of the uncovered PSU, if you don't mind. Thanks.

OK, I'm confused. 5VDC & 12VDC have been very common internal voltages for computers for decades, regardless of the input voltage. Modulated video aside, STs from various parts of the world are virtually identical from a hardware standpoint. I'm not sure why you would have expected to see much lower DC voltages to the motherboard. Either way, all STs, regardless of their country of origin, require 5VDC and12VDC internally, to the motherboard.

Yes, and those voltages are perfectly normal. The purpose of a power supply is to supply your device with a regulated, much lower DC voltage that all the components require, regardless of what the source voltage is. In your case, the PSU is designed for 220VAC, 50Hz provided in the U.K., while in the U.S. the PSU is designed for 120VAC, 60Hz. They both provide 5VDC and 12VDC to your STE.

I used the Mean Well RPD-60A, also from Digi-Key.

No, they are most definitely not multi-voltage compatible. They will only work with the normal voltage from the country of origin for the ST. You will need to either purchase some sort of Step-Up transformer or replace the power supply. I recently did a full conversion on a U.K. 1040 STE to U.S. STE and I replace the power supply with a cheap one I purchased from Digi-Key for about $20. It works great. I also replaced the TOS roms and the keyboard, but those aren't really necessary if you don't want to do them.

ParanoidLittleMan is behind most, if not all, of the HD versions that have appeared over the years. I've checked his site and he doesn't show one, so I'd be willing to say that there isn't, but maybe someone else will pipe up.

That's what I was thinking too, but a second opinion is certainly appreciated. I'm going to socket all of my non-socketed chips, which is pretty much everything except for GTIA, ANTIC, SALLY, PIA, POKEY, and memory. I'm going to replace the existing sockets with better quality sockets, precision sockets like we used on the 1088XEL in the case of the big 40-pin chips and the BASIC and OS chips. This will make it easier to troubleshoot, modify, upgrade in the future. I'm also ordering replacements for all of the 74LS and CD40 stuff. If she's not running after this, I'll know it's something more basic like an open or a short that my old eyes just aren't catching. Thanks!

OK, I'm planning to just order all of the LS chips, and sockets to go with them since those aren't socketed on my board. According to the SAMs manual, I have a discrepancy. U26 & U27 are multiplexers and are listed in the SAMS guide as 74LS158. However, my board has 74LS258 chips. I've looked and can't tell that there's any major difference between the two. I bought my 800XL brand new back in the day and it's never had any work done on it, so I'm assuming the 74LS258 chips are factory and that's what I'll replace with. What do you guys think?

I'm not sure if you just accidentally transposed some numbers, and obviously the ones you used worked, but the diode and transistor numbers you have listed are incorrect. I didn't think I was seeing the same numbers you were listing, but when you posted that last, really clear image of the schematic, that clinched it. The correct part numbers for the diodes is 1N914, not 1N916, and the correct part number for the transistor is 2N3904, not 2N9304. So, to clarify, the required parts list is: 1N914 diodes x2 2N3904 transistor 100 ohm resistor 150 ohm resistor 10K ohm resistor

I’ll have to check. I doubt I can just swap easily because, one, I probably don’t have another lying around, and two, I’m pretty sure it isn’t socketed on my board. I’ll check when I get home and get some replacement parts and sockets ordered. Thanks!

I agree with you, but I'd still like to see an image of the waveform from the collector of Q8 from a good 800XL for reference.

I think I may have found something amiss. I've been stepping through the troubleshooting section of the SAMS 800XL service guide and I was looking good until I hit the clock and dividers section. I don't think I'm seeing a 3.58MHz waveform at the collector of Q8. I tells what to check if you don't have it or it doesn't look good, but I'd like to see the waveform someone is getting from a known good 800XL so that I can compare it to mine. Thanks.

I never used Timewise back in the day, and certainly wouldn't use it today, but I can appreciate those that do wanting it to work correctly. I see that it requires BASIC, so can I assume that it is actually a BASIC program? If so, I wouldn't think it would be too hard to correct whatever subroutines control date entry and date calculations if someone were so inclined to do so. I guess it all depends on how well written, organized, and documented the program is. The most direct method would seem to be to update any date entry, calculation, and storage subroutines to only allow four digit years. Of course, that would slightly increase the record storage size, so that would impact how many records could be stored, but it would probably worth the trade-off to those wanting to use the program today.

As far as your question about Sync, with SysCheck unattached, no, it doesn't stay low after a few seconds. It continues to pulse like the original pictures I showed for Sync. A longer stretch at high, then drops to more or less zero, then starts pulsing.

OK, I misunderstood. All of my original waveforms were taken from my stock 800XL without my SysCheck attached. With SysCheck attached, this is what I see for Refresh MMU pin 11 ANTIC pin 8 I think these look more like what you were originally describing. All the others look more or less identical to the ones I took before, without the SysCheck attached. So, from what I can tell, nothing looks really amiss in any of the signals that I've checked so far.

I’m worried about “lifting” a pin. I’m worried about bending a pin and breaking it off. I’ve seen others reference bending a pin. How do you guys go about doing that then reinserting the chip into the socket without snapping it off?

I'm not sure what was wrong about tf_hh's post, but I did go ahead and check the points he'd mentioned. Here's Sync from CPU pin 7. I think it looks as expected from his original description. These next two are Refresh from MMU pin 11 and ANTIC pin 8, respectively. I don't think these two look quite like he'd described, originally saying that they would be an almost all-time low signal. That doesn't really seem to describe what I'm seeing here. The next three are PHI2 from CPU pin 39, ANTIC pin 29, and GTIA pin 30, respectively. They're not identical, but the all look fairly similar and relatively close. These final two are PHI0 from ANTIC pin 34 and CPU pin 37. Again, not identical, but very, very close. So, to me, the only ones that look suspect, at least from what tf_hh described I should be seeing is the two Refresh signals from MMU pin 11 and ANTIC pin 8. He said that if it was missing to check traces for continuity. Well, the signal isn't missing. It just isn't quite what I was expecting. Where does the Refresh signal originate and what might be causing it to look so abnormal, if in fact it does? I guess it's time to read through some more of the SAM's 800XL service guide and study the schematic some more. What do the rest of you think? Anything ring a bell with anyone here? Thanks.

I have an oscilloscope and can check those points. Which points should I check? Anything that can help narrow it down a little would be appreciated, even if I still have to wind up swapping a few chips.

Well, I received my Sys-Check v2.2 BBU today and tried it out on my 800XL. No luck. I got more than I have been getting, which was nothing but a static green screen (see the first post), but the Sys-Check menu doesn't come up. I do get some garbled graphics on the screen similar, but different every time. They all seem to lean towards the bluer end of the spectrum. I'm attaching four different boot videos so you can see what I mean. As I said, all four similar and blueish, but not quite the same. No menu, no perceived input from pressing the keys. I've verified that the dip switches on my Sys-Check are all set properly. To recap, I've already swapped ANTIC, GTIA, CPU & PIA with my 1088XEL. All of my 800XL chips work perfectly in my 1088XEL and my XEL's chips make no difference when used in the 800XL. I've swapped all of the RAM chips with new ones that I purchased. Pretty much the only socketed chip that I haven't tried swapping is the POKEY. After this I'll have to wait for my rework station and start pulling chips off the board, pick up new ones, install sockets and try the new chips until I find something that works. Any ideas? Do the videos ring any bells with anyone? Thanks.

Well, I can certainly see how that could happen, and like I said, I’ve answered to a lot worse than Bob in my time.

I doubt the ST is pushing much power out of the audio out. Are your speakers powered? If not, you're probably never going to get much of anything out of them.

Well, my SIO2PC-USB Dual Port died mysteriously. I'd emailed about my issues and he tried to help me troubleshoot it for a bit, but we didn't have any luck. He finally just said he was sending me a new one and asked me to return the old one. He's great BTW, in case I didn't mention it. Great products and great service. Anyway, that was just a week or so before I asked him about the version, and he was OK then. A lot can happen in a short time though, so who knows? Like you, I hope he and his family are doing well.

Does anyone have any idea what the most recent version is? I'm running 3.0.14. I've emailed Steve a couple of times trying to determine if there's a newer version and how I go about getting it if there is, but I haven't heard anything back. I know Steve has a family and a life and is busy but even though it sometimes takes him a while to respond, he usually does respond. I've emailed a couple of times over the past month or so and can't seem to get a response from him.

Does it still count as CIB if the top flap portion of the box has been completely cut away? I mean, can it be CIB if the box itself isn't complete?

Yes, I think that would be wise. I've never had any trouble with Brad at Best personally, but I hear he's getting quirkier by the day, and I certainly have no reason to disbelieve all of the many, many stories I've read of the nightmares others have had dealing with him. Dealing with Marlin is nothing but a joy. You can't go wrong with The Brewing Academy.