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new PAL (are they even available) and replacing the chip, or should i conside getting a new used c-64. are there any software programs to test the hardware on a c-64. i'm gonna look in the libraries when i'm done typing this. thanks, hari ------------ Category 4, Topic 40 Message 4 Sat Jan 01, 1994 T.SAUVE [Hari Seldon] at 04:26 EST also, how likely is it that my 1670 modem might be the culprit? I had my computer on for over 8 hours without a 'reset7. if it is the PLA, would it's problems happen because of heat or because of a program trying to perform a certain fufunction? that's all thanks agagin hari ------------ Category 4, Topic 40 Message 5 Mon Jan 03, 1994 C128.JBEE at 15:25 EST > T.SAUVE [Hari Seldon] > yeah, its an older commie 64. the motherboard says its copywrited > 1983 and the artwork for the board says it's rev 'b'. > is it worth the hassle of getting a new PAL (are theyeven available) As long as the power supply is okay, yes, it is worth it. They are available from the Grapevine Group and cost about $10. ------------ Category 4, Topic 40 Message 6 Mon Jan 03, 1994 C128.JBEE at 15:27 EST > T.SAUVE [Hari Seldon] > also, how likely is it that my 1670 modem might be the culprit? Very unlikely. Though it is likely the power supply (or one of the regulators) is weak and the extra drain of the modem is pushing the power supply to the limit. The most likely cause is a defective chip, that once it gets hot, goes south. The chips inside a C-64 get hot anyways, so you might be able to stave off any repairs now or in the future by simply by putting heat sinks on all the hot chips. They would be in the upper row of ROM sockets between the user port and RF box. Heatsinks are cheap, even from Radio Shack. I would also consider removing that cardboard (coated) RF shield, I think the only thing it is really effective at is trapping in the heat. I would double check the power supply to be sure that it is functioning properly and putting out the correct voltage. ------------ ************ Topic 41 Thu Dec 30, 1993 CBM-ED [e.g.bell] at 07:46 EST Sub: Align Your 1581 I had to do an alignment on my 1581 from the seat-of-my-pants, and I found out that it is not all that hard to do. Here is the procedure. Proceed at your own risk! :) 1 message(s) total. ************ ------------ Category 4, Topic 41 Message 1 Thu Dec 30, 1993 CBM-ED [e.g.bell] at 08:06 EST I was in the middle of a heavy day of copying. HEAVY! I am trying to get my library organized before starting on another major project. After about 3 hours, one of my 1581's came up lame. It would not read any disks at all... if it returned error messages at all, they were error 27 types on track 40, the directory track. I went out and bought a cleaning kit, intending to dutifully lock the barn door now that the horse had escaped. Unfortunately, my problems were more serious than this. I then got an inspiration. I tried to format a disk, and it worked. The disk formatted fine. I put the disk into my other 1581 and the other drive would not read it. My drive was out of alignment. I am not a technician... just someone who will open his equipment in the face of a problem it usually takes a technician to fix. After all, now it has to go to be repaired anyway. What is the worst I can do? (I have heard the arguments both ways on this. :) Here is what I found, step by step. Proceed at your own risk. Neither I nor GEnie nor the Commodore RT will accept any responsibility for your actions from here on.... First, though this should be a given... remove all plugs/cables from the drive unit. Flip the drive over and remove the 2 philips head screws holding the case halves together. Flip the drive back upright, catching the screws you just removed. Set them aside for later reassembly. The drive mechanism is attached to the bottom of the case by 4 philips screws, 2 on each side of the mechanism. Remove these and place them somewhere they won't get lost. This will free the drive mechanism except for the ribbon cable and one other connection. They don't need to be removed though. Lift the drive mechanism and you will see on each side 2 more phillips head screws holding the mechanism to the mounting plate. Remove these and place them with the others. Now you will need a utility knife. On each side of the drive mechanism there is a piece of tape holding the top of the drive mechanism to the bottom. The top is just a thin metal shield. You are getting close to where you have to be now. Once you slice the tape, remove this cover and you will see what you need to see to do this final part of the job. I had done an alignment on a 1541 years ago, which is why I was even willing to attempt this, and hoped the job would be similar. It was. In the back left corner of the drive mechanism is a round part held down by 2 tiny phillips head screws in slotted bosses. The slots allow the round part to be rotated when the screws are loosened, which is apparently what is required to align the drive. I used my utility knife to scribe a match-mark on the boss so I could restore the thing to its original setting in case my attempt went down in flames. I don't know why... it didn't work anyway.... guess I just have this man thing that makes me want to hide the fact that I'm a total idiot from any tech that might later have to come in and clean up my mess. :) Anyway, I made marks. Then I loosened the screws and adjusted, tightened, plugged in, etc. several times. Here is the part that ultimately brought me success, and I say it AGAIN with the disclaimer. Neither I nor GEnie nor the Commodore RT staff will accept any responsibility for anything you do to your drive or yourself if you decide to take this route. I got tired of plugging and unplugging, so I plugged the cables back in and was VERY careful where I put my fingers. I then started to make the adjustments and test immediately for a directory. Bottom line, my drive is working again as good as new. Haven't reassembled it just yet as I *do* have a good working understanding of Murphy's laws and corollaries. I'm waiting awhile because I *know* what always seems to happen when you get cocky and put everything back together again. There it is. Again... PROCEED AT *YOUR OWN* RISK. I don't think there are any 1581's still in warranty so that is probably not a concer, but there is no warranty on you. :) ------------ ************ Topic 42 Fri Dec 31, 1993 W.SHRAKE [ward] at 11:39 EST Sub: addresses of companies I'm trying to find out the addresses of older Commodore companies. Specifically, I want to know how to contact 'Chip Level Designs.' Others would probably like current company addresses, too. Thanx! 3 message(s) total. ************ ------------ Category 4, Topic 42 Message 1 Fri Dec 31, 1993 W.SHRAKE [ward] at 11:40 EST Anyone have the address or phone number, or some way to reach a company called 'Chip Level Designs'? They made some cool C64 upgrade stuff, and I'd like to get some of it, if I could. Thanks! ------------ Category 4, Topic 42 Message 2 Fri Dec 31, 1993 C.OGLE2 [V128_B.Stick] at 12:17 EST Ward... I'm afraid I haven't any current info about Chip Level Designs, but I can give you the older # & address...maybe you could track them down. I got this out of a 1988 gazette, (503) 861-1622 PO Box 603,astoria,OR 97103- 0603... Good luck :) ------------ Category 4, Topic 42 Message 3 Fri Dec 31, 1993 C128.JBEE at 12:25 EST As far as I know, they are out of business. Use to be one of the former members of Basement Boys. (Fast Hack'em) ------------ ************ Topic 43 Sun Jan 09, 1994 F.WILSON4 at 22:28 EST Sub: I Trashed a '71 please help. I have a 128 D the internal drive went comput. 5 message(s) total. ************ ------------ Category 4, Topic 43 Message 1 Sun Jan 09, 1994 F.WILSON4 at 22:31 EST I put a disk in my internal drive and the drive made a LOUD BANG. The 'puter wouln't do anthing then. I trans planted the drive from an external drive. I want to know if anyone can look at my drive now. please let me know. Fred(Daddie 2 B) PS I trans plantedthe drive after it broke. ------------ Category 4, Topic 43 Message 2 Mon Jan 10, 1994 C128.JBEE at 00:09 EST Fred, here is the number: 307-745-7077 Earl Harvey (E.HARVEY). As I mentioned in the RTC, be sure the heads are intact or otherwise the drive is not work fixing. ------------ Category 4, Topic 43 Message 3 Mon Jan 10, 1994 F.WILSON4 at 23:02 EST JBEE Thanks for the number I din't get around to E-Mailing Earl. I am pretty sure everything is in one piece. I will give him a call. Where does Earl live so I don't call too late due to the time zones. Once again Thanks Fred. ------------ Category 4, Topic 43 Message 4 Tue Jan 11, 1994 C128.JBEE at 02:35 EST Laramie, WY :-) ------------ Category 4, Topic 43 Message 5 Sat Jan 22, 1994 F.WILSON4 at 21:35 EST THIS topic is no longer in effect. F.WILSON4 ------------ ************ Topic 44 Mon Jan 10, 1994 AMFORD at 01:54 EST Sub: Dead C128 Dead C128 that doesn't come up. Just a blank screen. 5 message(s) total. ************ ------------ Category 4, Topic 44 Message 1 Mon Jan 10, 1994 AMFORD at 01:58 EST I have a C128 that does not boot up. No screen output. Doesn't even reset the drives. I am remembering correctly that this is probably the Z80 chip? (One of the very few chips actually soldered TO the board. grumble grumble.) ------------ Category 4, Topic 44 Message 2 Mon Jan 10, 1994 C128.JBEE at 16:06 EST Did you check all the fuses and have you checked the power supply to make sure it is working correctly? ------------ Category 4, Topic 44 Message 3 Tue Jan 11, 1994 H.HERMAN1 at 01:15 EST Alan, I seem to recall that same thing: about the z80. At least that a bad z80 will not let the 128 boot. Sure hope you have another 'puter til you get this fixed! Howie ------------ Category 4, Topic 44 Message 4 Sun Jan 16, 1994 AMFORD at 16:08 EST I don't even plug in a 'bad' computer's power supply. Always use on of my good working supplies that I am sure of. Yeah, I popped open the C128 to check the fuse (and see how few chips were socketed). About the only thing that comes on is the red LED. :) Howie, only have two reserve C128s. But I got a daughter wanting a computer, so may have to swap out the bbs's C64 and let her blast those space aliens. Er, work on her reading. ------------ Category 4, Topic 44 Message 5 Sun Jan 16, 1994 C128.JBEE at 19:05 EST Assuming you have checked the power supply and you have no screen what so ever, I would hazard a guess that it is (in this order) 1) the 8721 (PLA) 2) the VDC 3) the 8722 (MMU) 4) the 8502 CPu A lot of times when the VDC dies, it prevents the system from booting, though you MAY be able to go into C-64 mode. All but the 8502 should be socketed. ------------ 4