hashy Posted December 18, 2013 Share Posted December 18, 2013 Hey, well here it is. i picked up an atari 400 with a 401, 1050, and a 1025 all for $40 at a local store. heres muh problem it works so far but i cant use it lol. the keyboard dose not work the system reset and break keys do. well i looked into it and well the keyboard does work i tested it with my multimeter cant say all keys do but more then the 2 that work when its fired up. so the next thing i did was look into it more found that the pokey chip did most of the workins on the kb. well i figured it was bad so i pulled out the 5200 i had layin around and swapped the chip........ still no go does anyone have any ideas on what else it could be??? i would love to get this thing working again ive always wanted an atari computer now i have one but it needs some TLC! Thanks Quote Link to comment Share on other sites More sharing options...
BillC Posted December 18, 2013 Share Posted December 18, 2013 There are 2 4051 multiplexer ICs between POKEY and the keyboard, one or both of which are most likely the cause of your problem Quote Link to comment Share on other sites More sharing options...
russg Posted December 18, 2013 Share Posted December 18, 2013 (edited) Hey, well here it is. i picked up an atari 400 with a 401, 1050, and a 1025 all for $40 at a local store. heres muh problem it works so far but i cant use it lol. the keyboard dose not work the system reset and break keys do. well i looked into it and well the keyboard does work i tested it with my multimeter cant say all keys do but more then the 2 that work when its fired up. so the next thing i did was look into it more found that the pokey chip did most of the workins on the kb. well i figured it was bad so i pulled out the 5200 i had layin around and swapped the chip........ still no go does anyone have any ideas on what else it could be??? i would love to get this thing working again ive always wanted an atari computer now i have one but it needs some TLC! Thanks two chips near keyboard connector are known to be sometimes bad. U24 and U25. 4051 chips. The 400 probably has socketed chips. Best electronics has 4051 for $.69. The problem is that is too little an order, I don't know. My 800XL has RCA H349 and another has NEC 8436B7 both 4051. The thing would be to get two 4051 and try them out. But you don't have another one. ( I don't know what an Atari 401, maybe a 400 board?) Oh, BillC beat me to it. Edited December 18, 2013 by russg Quote Link to comment Share on other sites More sharing options...
hashy Posted December 18, 2013 Author Share Posted December 18, 2013 woops yeah a 410 program recorder thanks for the info tho ima look see if i have any thing here to replace them with if not i will order them online thanks again i will update as i go Quote Link to comment Share on other sites More sharing options...
russg Posted December 18, 2013 Share Posted December 18, 2013 woops yeah a 410 program recorder thanks for the info tho ima look see if i have any thing here to replace them with if not i will order them online thanks again i will update as i go Looking inside an 800. The 4051 are z103 and z104. At any rate, the two 16 pin chips near the keyboard connector. Quote Link to comment Share on other sites More sharing options...
russg Posted December 19, 2013 Share Posted December 19, 2013 Looking inside an 800. The 4051 are z103 and z104. At any rate, the two 16 pin chips near the keyboard connector. Never open up an 800. Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted December 19, 2013 Share Posted December 19, 2013 Never open up an 800. 800s aren't that bad. just get the speaker in right, and don't let it fall out while you plug in the keyboard 1 Quote Link to comment Share on other sites More sharing options...
+Stephen Posted December 19, 2013 Share Posted December 19, 2013 Never open up an 800. No no no - definitely open an 800, it's the only way to get the Incognito installed 1 Quote Link to comment Share on other sites More sharing options...
Rybags Posted December 19, 2013 Share Posted December 19, 2013 4051 is still a common off-the-shelf part and can be had at any half decent electronics outfit. Same applies to most of the minor 7400 and 4000 series ICs inside Ataris although there are various technology and variants like CMOS, high current, low voltage etc. I've not heard much of 400 keyboard problems but 2 things worth trying out first: - pull the ribbon cable off and re-attach, the pins can get oxidization. - swap the 2x 4051 ICs, see if anything changes. Quote Link to comment Share on other sites More sharing options...
russg Posted December 19, 2013 Share Posted December 19, 2013 (edited) 800s aren't that bad. just get the speaker in right, and don't let it fall out while you plug in the keyboard I have two 800. One, I can put the speaker in the circular plastic of the case and the other doesn't have that circular speaker place. The one without the circle space is, I think, a replacement speaker, the magnet is too big for the circular space, even if it had one. My problem is remembering how it goes back together after I take it apart. I have to take apart the second one to see how it comes apart to put the other back together. There are about a dozen screws, six longer ones and six shorter machine screws. I'm a bit memory challenged. On another note, one of my 800 has a bit too much green to the screen. I can't find a pot to turn to adjust it on the outside of the case. There is a hole on the bottom that seems to lead to a pot. That internal 'pot' seems to take a number 2 allen wrench. Inserting and turning it does nothing to the background blue color. Edited December 19, 2013 by russg Quote Link to comment Share on other sites More sharing options...
BillC Posted December 19, 2013 Share Posted December 19, 2013 (edited) I have two 800. One, I can put the speaker in the circular plastic of the case and the other doesn't have that circular speaker place. The one without the circle space is, I think, a replacement speaker, the magnet is too big for the circular space, even if it had one. My problem is remembering how it goes back together after I take it apart. I have to take apart the second one to see how it comes apart to put the other back together. There are about a dozen screws, six longer ones and six shorter machine screws. I'm a bit memory challenged. On another note, one of my 800 has a bit too much green to the screen. I can't find a pot to turn to adjust it on the outside of the case. There is a hole on the bottom that seems to lead to a pot. That internal 'pot' seems to take a number 2 allen wrench. Inserting and turning it does nothing to the background blue color. The color adjustment pot is on the CPU card, if you take the RAM bay cover off you will see there is a hole in the back of the RF shield to access this pot. Here is a link to a post I made showing this access hole: http://atariage.com/forums/topic/177900-atari-800-color-is-green/?do=findComment&comment=2221044 Edited December 19, 2013 by BillC Quote Link to comment Share on other sites More sharing options...
russg Posted December 19, 2013 Share Posted December 19, 2013 The color adjustment pot is on the CPU card, if you take the RAM bay cover off you will see there is a hole in the back of the RF shield to access this pot. Here is a link to a post I made showing this access hole: http://atariage.com/forums/topic/177900-atari-800-color-is-green/?do=findComment&comment=2221044 YES! That was it. Thanks. Quote Link to comment Share on other sites More sharing options...
19Echo Posted December 19, 2013 Share Posted December 19, 2013 <--------- Has never opened up his 800 but wonders why there are 2 aftermarket speaker wires coming out of it Quote Link to comment Share on other sites More sharing options...
russg Posted December 19, 2013 Share Posted December 19, 2013 <--------- Has never opened up his 800 but wonders why there are 2 aftermarket speaker wires coming out of it How do you know those are speaker wires? The built in 800 speaker only does key clicks. Other sounds only go out the RF or composite port. If you connect a speaker to those wires, does it make the key click sounds, or does it make game sounds? Quote Link to comment Share on other sites More sharing options...
Rybags Posted December 19, 2013 Share Posted December 19, 2013 Might be for some other mod like dual OS switcher. Quote Link to comment Share on other sites More sharing options...
hashy Posted December 19, 2013 Author Share Posted December 19, 2013 welp could not find any replacments lying around so i got some ordered. they ended up being like 3 bucks with shipping so not so bad. i will try swapping the 2 around to see if i get any changes. the keyboard has been unhooked and plugged back in many times now lol. when i first took it apart oxidization or corrosion were things i was looking for but it seems to be really clean inside for its age . i was aslo wondering if anyone knows details on the 48k ram upgrade? i read that there was some soldering to do. not an issue for me just need to know what..... lol and does it use the 16k board with new chips or does it require a new board? Thanks Again For The Help So Far ! i hope to be in need of some software soon , and i want to find a good use for it. i dont like just looking at muh old HW it needs to be running... still plenty of cycles left in this old cpu Quote Link to comment Share on other sites More sharing options...
BillC Posted December 19, 2013 Share Posted December 19, 2013 welp could not find any replacments lying around so i got some ordered. they ended up being like 3 bucks with shipping so not so bad. i will try swapping the 2 around to see if i get any changes. the keyboard has been unhooked and plugged back in many times now lol. when i first took it apart oxidization or corrosion were things i was looking for but it seems to be really clean inside for its age . i was aslo wondering if anyone knows details on the 48k ram upgrade? i read that there was some soldering to do. not an issue for me just need to know what..... lol and does it use the 16k board with new chips or does it require a new board? Thanks Again For The Help So Far ! i hope to be in need of some software soon , and i want to find a good use for it. i dont like just looking at muh old HW it needs to be running... still plenty of cycles left in this old cpu If you're not in a hurry to get your 400 upgraded Candle is supposed to be releasing his Incognito Lite upgrade in a bit, but it could also be a year or so. It all depends on how much time he has available and his other projects. Quote Link to comment Share on other sites More sharing options...
hashy Posted December 20, 2013 Author Share Posted December 20, 2013 well i swapped the 2 chips they must be bad because the break key doesnt work now lol. the new chips are on the way hopefully they solve muh problem... Quote Link to comment Share on other sites More sharing options...
hashy Posted December 22, 2013 Author Share Posted December 22, 2013 (edited) yay! the chips came in today. it worked all the keys work!! . the cassette recorder works just have one peice of software. however the disk drive does not. its like there is no drive at all. it does not attempt to read a disk, does anyone know what this might be? its a 1050 Edited December 22, 2013 by hashy Quote Link to comment Share on other sites More sharing options...
Rybags Posted December 22, 2013 Share Posted December 22, 2013 1050 has 2 recessed device select switches accessable from the back. Drive ID has to be 1 to be able to boot. Fairly sure both switches set to the left is what you need there. Quote Link to comment Share on other sites More sharing options...
hashy Posted December 22, 2013 Author Share Posted December 22, 2013 yeah ive checked that ive tried diffirent cables still nothing... ima take it apart more maybe today Quote Link to comment Share on other sites More sharing options...
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