flashjazzcat Posted August 16, 2011 Share Posted August 16, 2011 What's to say you couldn't put something else in those bays... Ooo... like a sandwich? I was thinking of mounting an SIO2SD in one of the bays instead of a drive, but the sandwich idea is a good one. Looks like there'd be room for an entire loaf in there. In fact - fit a breadbin. Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 16, 2011 Share Posted August 16, 2011 The first part - C124 is not a capacitor and is mounted flat to the board. What is on both of mine is a jumper and a 5100ohm resistor. (see pic) My parts may be different since I have the new modem on both machines. Bob Sure! I promise to be more careful... Thanks bob1200XL, here are the last ones that I'm still trying to confirm. Almost 400 down, only 14 to go: C124 (above and left of U35, mounted vertically) I assume that it's a .1uf but it's missing from both schematics and the BOM C134 (below diodes under relay) should be .1uf, some sources say ceramic, some say electrolytic, which is it? CR14 (below Y3) missing on both schematics, id #? if visible Q3 (below RF channel switch) listed in schematics as 2N3904 listed in BOM as 2N3906, which is it? Q8 (next to RF modulator) listed in schematics as 2N3906 listed in BOM as 2N3904, which is it? R7 value? (above J8, mounted vertically) R25 value? (below U8) R45 value? (below U21) R59 value? (above VR1, mounted vertically) R62 value? (touching left side of modulator) R141 value? (below RF switch, mounted upright) R143 value? (below diodes under relay, mounted upright) R145 value? (to left of U39 mounted upright) R153 value? (next to RF modulator) That should be everything, I located all of them on the board and I'm attaching a picture of the bare board to help in locating them, so hopefully it's not too horrible for you. Thanks for the help. cheers, v Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 16, 2011 Share Posted August 16, 2011 Yes, C134 is an electrolytic - + down. (I would expect ceramic... can't imagine why it needs to be electrolytic) CR14 - I have one, cathode up. Q3 - 2N3906 Q8 - cannot read, looks like 2N3904 R7 - 3K R25 - can't tell between red, brown and orange. Either 560, 5600, or 56K. I'll measure it. Bob Sure! I promise to be more careful... Thanks bob1200XL, here are the last ones that I'm still trying to confirm. Almost 400 down, only 14 to go: C124 (above and left of U35, mounted vertically) I assume that it's a .1uf but it's missing from both schematics and the BOM C134 (below diodes under relay) should be .1uf, some sources say ceramic, some say electrolytic, which is it? CR14 (below Y3) missing on both schematics, id #? if visible Q3 (below RF channel switch) listed in schematics as 2N3904 listed in BOM as 2N3906, which is it? Q8 (next to RF modulator) listed in schematics as 2N3906 listed in BOM as 2N3904, which is it? R7 value? (above J8, mounted vertically) R25 value? (below U8) R45 value? (below U21) R59 value? (above VR1, mounted vertically) R62 value? (touching left side of modulator) R141 value? (below RF switch, mounted upright) R143 value? (below diodes under relay, mounted upright) R145 value? (to left of U39 mounted upright) R153 value? (next to RF modulator) That should be everything, I located all of them on the board and I'm attaching a picture of the bare board to help in locating them, so hopefully it's not too horrible for you. Thanks for the help. cheers, v Quote Link to comment Share on other sites More sharing options...
JohnBuell Posted August 16, 2011 Share Posted August 16, 2011 What's to say you couldn't put something else in those bays... Ooo... like a sandwich? I was thinking of mounting an SIO2SD in one of the bays instead of a drive, but the sandwich idea is a good one. Looks like there'd be room for an entire loaf in there. In fact - fit a breadbin. Reminds me of the very first G4 Apple XServe I worked with - the Engineers would jokingly say that you could use the empty drive bays for heating Pop Tarts. Never tried.... Quote Link to comment Share on other sites More sharing options...
mimo Posted August 16, 2011 Share Posted August 16, 2011 This thread makes me want to pull out my 1400XL board and see if I could populate it and shove it in a 1200XL case. Then again I'm not exactly sure what I'd do with it once I did that, it's not like the 1400XL is anything all that special. The 1450XLD on the other hand... Heh... I don't see the attraction of two huge single sided disk drives these days. A 1200XL with integral PBI, on the other hand: now that would be something. Is there anything else that the 1450XLD offers over the 1400XL, apart from the disk drives? nope, well not according to the product spec .pdf over at the Atari Museum http://www.atarimuseum.com/computers/8BITS/XL/1450xld/1450xld.html Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 17, 2011 Share Posted August 17, 2011 R45 is 3K R59 is 620 ohms R62 is 1K R141 is 100 ohms The mounting pads for R143 are empty - R143 is not mounted R145 is also not mounted R153 is 1K Bob Sure! I promise to be more careful... Thanks bob1200XL, here are the last ones that I'm still trying to confirm. Almost 400 down, only 14 to go: C124 (above and left of U35, mounted vertically) I assume that it's a .1uf but it's missing from both schematics and the BOM C134 (below diodes under relay) should be .1uf, some sources say ceramic, some say electrolytic, which is it? CR14 (below Y3) missing on both schematics, id #? if visible Q3 (below RF channel switch) listed in schematics as 2N3904 listed in BOM as 2N3906, which is it? Q8 (next to RF modulator) listed in schematics as 2N3906 listed in BOM as 2N3904, which is it? R7 value? (above J8, mounted vertically) R25 value? (below U8) R45 value? (below U21) R59 value? (above VR1, mounted vertically) R62 value? (touching left side of modulator) R141 value? (below RF switch, mounted upright) R143 value? (below diodes under relay, mounted upright) R145 value? (to left of U39 mounted upright) R153 value? (next to RF modulator) That should be everything, I located all of them on the board and I'm attaching a picture of the bare board to help in locating them, so hopefully it's not too horrible for you. Thanks for the help. cheers, v Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 17, 2011 Share Posted August 17, 2011 ... and R25 is 56K Bob Sure! I promise to be more careful... Thanks bob1200XL, here are the last ones that I'm still trying to confirm. Almost 400 down, only 14 to go: C124 (above and left of U35, mounted vertically) I assume that it's a .1uf but it's missing from both schematics and the BOM C134 (below diodes under relay) should be .1uf, some sources say ceramic, some say electrolytic, which is it? CR14 (below Y3) missing on both schematics, id #? if visible Q3 (below RF channel switch) listed in schematics as 2N3904 listed in BOM as 2N3906, which is it? Q8 (next to RF modulator) listed in schematics as 2N3906 listed in BOM as 2N3904, which is it? R7 value? (above J8, mounted vertically) R25 value? (below U8) R45 value? (below U21) R59 value? (above VR1, mounted vertically) R62 value? (touching left side of modulator) R141 value? (below RF switch, mounted upright) R143 value? (below diodes under relay, mounted upright) R145 value? (to left of U39 mounted upright) R153 value? (next to RF modulator) That should be everything, I located all of them on the board and I'm attaching a picture of the bare board to help in locating them, so hopefully it's not too horrible for you. Thanks for the help. cheers, v Quote Link to comment Share on other sites More sharing options...
+MrFish Posted August 17, 2011 Share Posted August 17, 2011 What's to say you couldn't put something else in those bays... Ooo... like a sandwich? I was thinking of mounting an SIO2SD in one of the bays instead of a drive, but the sandwich idea is a good one. Looks like there'd be room for an entire loaf in there. In fact - fit a breadbin. "A sandwich"... now you're thinking. This gives new meaning to the phrase, "storage options". How many sandwich bites does your computer hold? The whole dining/computing issue has been highly neglected in my opinion. Quote Link to comment Share on other sites More sharing options...
sloopy Posted August 17, 2011 Share Posted August 17, 2011 and dont forget to have a pocket also for some chips... (or CornNuts! ) sloopy. Quote Link to comment Share on other sites More sharing options...
Havok69 Posted August 17, 2011 Share Posted August 17, 2011 What a neat project, I hope you're successful in getting this to work. The 1450XLD was my second favorite 8 bit after the 1200XL. I'll be really interested in seeing the machined case... Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted August 18, 2011 Share Posted August 18, 2011 (edited) I'm mad at all of you folks that jacked up the price of the bare boards. Only a few left, so best get them before they go up again. Edited August 18, 2011 by kheller2 Quote Link to comment Share on other sites More sharing options...
Vandal968 Posted August 19, 2011 Author Share Posted August 19, 2011 I'm mad at all of you folks that jacked up the price of the bare boards. Only a few left, so best get them before they go up again. Have the boards gone up from $25? cheers, c Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted August 19, 2011 Share Posted August 19, 2011 (edited) I'm mad at all of you folks that jacked up the price of the bare boards. Only a few left, so best get them before they go up again. Have the boards gone up from $25? cheers, c Yup.. $45 now. They don't have many left. Apparently folks have been buying them this past week. LOL BTW, did you get the latest 1450 pics I sent the other day? Edited August 19, 2011 by kheller2 Quote Link to comment Share on other sites More sharing options...
Vandal968 Posted August 19, 2011 Author Share Posted August 19, 2011 Yup.. $45 now. They don't have many left. Apparently folks have been buying them this past week. LOL BTW, did you get the latest 1450 pics I sent the other day? I figured that this thread would sell some 1450 hardware, that's why I didn't say what I was up to until I had all the tricky parts sourced. Of course, if I had mentioned it earlier, someone probably would have pointed me to the Atari BOM and saved me a lot of time. Tradeoffs.... Yes, I got those scans, they are excellent, thank you. I've been swamped, I only replied to your email about an hour ago. bob1200XL, thanks for all the info you posted. There are (of course) a couple of more discrepancies, for one thing, the jumpers at W3 and W4 are the opposite of what would be expected from reading the Atari BOM. This makes me think that it would be much safer to build this one out in your exact configuration with modem daughtercard since I can't rely on the data I've got for using the other chip and no one's got one to cross-reference. I was actually thinking about getting a second mobo just in case (maybe build one each way) but for $45 forget it. I've already got too much money in this project. There are a few chips that will need to be programmed, I've been cross-referencing the parts, and replacing old-school PAL's (special programmer required) with pin-compatible modern eeprom-based replacements. We're also going to need the data to program them, haven't figured that part out yet. The BIOS PROM should be easy enough to dump, not sure if that can be done with the PAL's or if we need a logic map for those. Assuming that the chip-programming works out, I'm probably going to have a small run of modem daughter-cards made. Shouldn't be too bad. cheers, c Quote Link to comment Share on other sites More sharing options...
Bryan Posted August 19, 2011 Share Posted August 19, 2011 I just bought 2 of the modem chips off ebay if anyone needs one. Finding an SC-01 for less than $40 is gonna be tricky. I used to have several before I got rid of most of my arcade boards. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted August 19, 2011 Share Posted August 19, 2011 That photo is just sick. Quote Link to comment Share on other sites More sharing options...
Vandal968 Posted August 19, 2011 Author Share Posted August 19, 2011 Finding an SC-01 for less than $40 is gonna be tricky. I used to have several before I got rid of most of my arcade boards. There's a guy selling the SC-01 for $36 delivered on eBay. That said, I'd hold off a little while longer, they're definitely still available from multiple sources, and if we discover a major show stopper (like the PAL chips) then having a $40 chip gathering dust in the closet for the next 20 years isn't going to do you any good. I'm going to try to release a 1.0 version of the BOM next week, it's very very close to being final. Which modem did you buy, the 74HC942 or the TI chip? cheers, v Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 19, 2011 Share Posted August 19, 2011 My experience has been that the PAL/GALs are not protected so we can copy them. GALs will emulate the 16L8 or whatever (or, you can use the old PALS - they're available cheap$) Just from the schematic, we could probably figure out what the logic is, anyway. The Freddie is going to be a problem... Bob Yup.. $45 now. They don't have many left. Apparently folks have been buying them this past week. LOL BTW, did you get the latest 1450 pics I sent the other day? I figured that this thread would sell some 1450 hardware, that's why I didn't say what I was up to until I had all the tricky parts sourced. Of course, if I had mentioned it earlier, someone probably would have pointed me to the Atari BOM and saved me a lot of time. Tradeoffs.... Yes, I got those scans, they are excellent, thank you. I've been swamped, I only replied to your email about an hour ago. bob1200XL, thanks for all the info you posted. There are (of course) a couple of more discrepancies, for one thing, the jumpers at W3 and W4 are the opposite of what would be expected from reading the Atari BOM. This makes me think that it would be much safer to build this one out in your exact configuration with modem daughtercard since I can't rely on the data I've got for using the other chip and no one's got one to cross-reference. I was actually thinking about getting a second mobo just in case (maybe build one each way) but for $45 forget it. I've already got too much money in this project. There are a few chips that will need to be programmed, I've been cross-referencing the parts, and replacing old-school PAL's (special programmer required) with pin-compatible modern eeprom-based replacements. We're also going to need the data to program them, haven't figured that part out yet. The BIOS PROM should be easy enough to dump, not sure if that can be done with the PAL's or if we need a logic map for those. Assuming that the chip-programming works out, I'm probably going to have a small run of modem daughter-cards made. Shouldn't be too bad. cheers, c Quote Link to comment Share on other sites More sharing options...
Bryan Posted August 19, 2011 Share Posted August 19, 2011 (edited) Which modem did you buy, the 74HC942 or the TI chip? 74HC942. The Freddie is going to be a problem... What's the problem with Freddie? Is it different in the 1450? EDIT: Just saw the post on page 1 about it...so it's still up in the air whether a 'modern' Freddie will work? Edited August 19, 2011 by Bryan Quote Link to comment Share on other sites More sharing options...
Vandal968 Posted August 19, 2011 Author Share Posted August 19, 2011 My experience has been that the PAL/GALs are not protected so we can copy them. GALs will emulate the 16L8 or whatever (or, you can use the old PALS - they're available cheap$) Just from the schematic, we could probably figure out what the logic is, anyway. The Freddie is going to be a problem... Bob Great. That's the part that I was most worried about. I don't think Freddie should be an issue, Best still has a bunch of them and ratty XEGS machines come up on eBay all the time. I saw one last week that went for $12 delivered (no keyboard, PSU, etc.) but perfect for stealing a chip. I couldn't bring myself to trash a whole machine for that one chip, although it was tempting. I ordered my Freddie from Best for $10. cheers, c Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted August 19, 2011 Share Posted August 19, 2011 (edited) Take a look at the equation PDF I posted in the old 1400 thread to see if the logic matches up. Edited August 20, 2011 by kheller2 Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 19, 2011 Share Posted August 19, 2011 No. I would imagine that if the Freddie chip were different, it would have had a different code name. We just can't copy one very well. But, we won't know for sure until we try one. Worst case, we make an adaptor to plug into the socket and use a CPLD. Personally, I'm going to run mine with SRAM so I don't need Freddie. Or, half that other stuff. All I want is the Voice and internal PBI. Not much call for a modem these days. Bob Which modem did you buy, the 74HC942 or the TI chip? 74HC942. The Freddie is going to be a problem... What's the problem with Freddie? Is it different in the 1450? EDIT: Just saw the post on page 1 about it...so it's still up in the air whether a 'modern' Freddie will work? Quote Link to comment Share on other sites More sharing options...
+Guitarman Posted August 19, 2011 Share Posted August 19, 2011 Well, I just jumped on the bandwagon!! Just ordered the 1450XLT board and the tech docs. Even if the buildout doesn't work, I figure it is the closest I'll ever come to owning a 1450XLT!!! LOL Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted August 19, 2011 Share Posted August 19, 2011 Where? Bob Take a look at the equation PDF I posted in the ore 1450 thread to see if the logic matches up. Quote Link to comment Share on other sites More sharing options...
+Guitarman Posted August 19, 2011 Share Posted August 19, 2011 Nothing to see here!!! LOL Quote Link to comment Share on other sites More sharing options...
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