_The Doctor__ Posted February 20, 2023 Share Posted February 20, 2023 replace that chip with an 'F08 in any event. Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 20, 2023 Author Share Posted February 20, 2023 these are the shots of the front and back thanks Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 (edited) Your color pot is cranked almost all the way... what color is the screen when it does boot? double check power supply voltage under load when boot is failing!!! Edited February 21, 2023 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 ok, go over the back solders of the sockets, and improve the damaged tracks with a jumper. In the photo Doctor, the screen is red. I have set the pot color to blue and measured the voltage. I have been turning it on and off and READY appeared, but now I am afraid to turn it off... Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 (edited) Don't be afraid, keep the meter on it, and power it off, wait a 12 full seconds and turn it back on, always wait a bit between power cycles on an XE so memory clears out. You can type BYE and the return key for self test or hold down option during power on for those tests, if your keyboard mylar is good. Edited February 21, 2023 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 I turned it off and again it shows nothing... the blue screen stays... Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 (edited) leave it off a little longer, pay attention to the voltage, if it comes up great if it doesn't leave it on for a bit and then press reset blue screen from Atari or blue screen from TV? make sure power switch is actually working. make sure cap near power switch, and all solde joint near power jack and switch are good, a marginal power switch may need cleaner in it and to be worked... Edited February 21, 2023 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 This is the image of the memories and the back, weld reinforcement and bridge with contact. Could the 0.1uF capacitors be too small? Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 did you read the message about a voltage reading after the swtch as we go? what blue screen, from TV no signal or from Atari? did you test a cold machine power on and a warm machine, reset or power switch flick.. etc. 13 minutes ago, _The Doctor__ said: leave it off a little longer, pay attention to the voltage, if it comes up great if it doesn't leave it on for a bit and then press reset blue screen from Atari or blue screen from TV? make sure power switch is actually working. make sure cap near power switch, and all solde joint near power jack and switch are good, a marginal power switch may need cleaner in it and to be worked... Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 About the voltage, I measure from the switch and it is always 4.99 to 4.98V, while it is on, or when I turn it on. The blue screen is from the atari, because I moved the color pot, when the READY does not appear it is blue, the times the READY came out it is red. I have tried warm and cold reboot. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 no, you are measuring the input of the switch, we need the output of the switch Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 Input off 5.13V - 5.14V Input on 5.00V Output Off 0.00V - 0.01V Output On 4.99V - 5.00V Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 You've got crap in some of the ram sockets where the chips pins insert (visible in your photo) and the sockets may have disturbed surrounding components please clean, blow out chip sockets and make sure chip pins are clean and straight, re seat. Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 Thanks -The Doctor- I took out all the memories, cleaned the sockets with contact cleaner and IPA and cleaned each memory, I checked and installed them, but it's still the same. I have noticed that sometimes when turning on it has an imperceptible sound (2 times) like "bup - bup". Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 21, 2023 Share Posted February 21, 2023 (edited) the other thing to check is without the chips in, is there intermittent connections when testing across all sockets etc as it appears some of the sockets are also two 8 pin sockets butted against each other. could be slightly askew. If you can get it to basic again. type bye and let the tests run. Edited February 21, 2023 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
TZJB Posted February 21, 2023 Share Posted February 21, 2023 (edited) The 0.1uF filter capacitors are there to prevent switching noise getting to the power bus and are specified by design. Each chip has it's own unless you own a 800XLF then you have to put one in for the Freddie chip! Talking of Freddie, do all of your DRAM address lines go back to Freddie correctly? RA7 to RA0 should go back to Freddie pins 25 to 32 respectively. Also check the CAS lines back to the MMMU. See attached diagrams courtesy of Jerzy Sobola. :- Edited February 21, 2023 by TZJB Quote Link to comment Share on other sites More sharing options...
TZJB Posted February 21, 2023 Share Posted February 21, 2023 14 hours ago, MikiPERU said: just checking the bottom of the board i saw this jumper on the MB74LS08, is it normal? Comparing this to your other pictures, I can confirm that this is a factory modification. They normally just short out the pins on the chip at the top where the wiring is. Quote Link to comment Share on other sites More sharing options...
TZJB Posted February 21, 2023 Share Posted February 21, 2023 (edited) Although this has nothing to do with the topic and the picture of the front of your 130XE main board is a bit blurry, I just picked up on R95 being 220R instead of 1K. I recommend that you change this resistor to the correct value otherwise the keyboad will fail prematurely if it hasn't already. It is located as the middle resistor in a bank of three just under the left side of the keyboard connector. Edited February 21, 2023 by TZJB Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 21, 2023 Author Share Posted February 21, 2023 Hello friends, I changed the 8-pin x 16-pin sockets, and I checked the track again but there is no improvement, the red screen continues. I'm going to wait to have a new team and test the other components, thanks for your help to _The Doctor_ , TZJB, TGB1718, xrbrevin, deffroe, MVladimir, BillC, marauder666, it's great to be part of this group, I'll post pictures later in better quality for your suggestions, a big hug Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 22, 2023 Author Share Posted February 22, 2023 Here I leave some photos, your suggestions and ideas are welcome Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 22, 2023 Share Posted February 22, 2023 It seems you are over heating and melting/distorting things, XE's can't take the heat, from the upper component side I see places where solder looks awfully close to the point it might short out. Please understand the traces can not take repeated heat, it views such things as abuse. If it continues to get worse it might be time to consider a helper or shipping it to be fixed. Please use bright lights and magnification to check your work very closely. You had progress and now it seems one step forward two steps back. Quote Link to comment Share on other sites More sharing options...
MikiPERU Posted February 22, 2023 Author Share Posted February 22, 2023 If it's true, it got very hot, I'm going to let it rest and see who can take a look here in Peru, thanks for the honest comment. Quote Link to comment Share on other sites More sharing options...
macsonny Posted February 22, 2023 Share Posted February 22, 2023 On 2/21/2023 at 12:51 PM, MikiPERU said: This is the image of the memories and the back, weld reinforcement and bridge with contact. Could the 0.1uF capacitors be too small? FYI - I have a 65XE that I upgraded to 1 130XE by just adding in a few extra memory chips. Interestingly ALL the 0.1uF capacitors for the memory chips were removed on my board for some reason. When I replaced them the machine refused to work so I just removed them again and all was fine. Not sure why it acted like this? Quote Link to comment Share on other sites More sharing options...
TZJB Posted February 22, 2023 Share Posted February 22, 2023 4 hours ago, macsonny said: FYI - I have a 65XE that I upgraded to 1 130XE by just adding in a few extra memory chips. Interestingly ALL the 0.1uF capacitors for the memory chips were removed on my board for some reason. When I replaced them the machine refused to work so I just removed them again and all was fine. Not sure why it acted like this? That is strange. A 65XE should have the 8 DRAM de-coupling capacitors next to the chips from manufacture. Obviously the second bank wouldn't have them as there wouldn't be anything to de-couple. Nevertheless I have always installed the extra capacitors when adding DRAM and not had an issue and that included the A8 wire commoning pin 1 for a 256K expansion. Maybe you had a short circuit that went away when the solder was removed as the traces are very close to one another? Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted February 22, 2023 Share Posted February 22, 2023 So I’m a little confused here on the actual issue that can be reproduced. When you turn it on after being off for a few minutes do you get a buz noise and a ready prompt? adjust the color pot so you get a light blue screen. once you get a Ready prompt, type bye and run the memory test. I’m curious if your OS and BASIC pass. Do you get and red blocks for anything? Take a picture. press reset and do you go back to a ready prompt? you should wait 20 seconds between power cycles (depending on the speed of your RAM draining) for your troubled board. Quote Link to comment Share on other sites More sharing options...
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