IBM 8512 VGA Monitor, 12": Difference between revisions
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==Known Issues== | ==Known Issues== | ||
As a first generation VGA monitor, the 8500 series has its shortcomings. A dot pitch of 0.41 makes the display fuzzy and monitor dims noticeably when drawing light-colored screens, though this is considered a design flaw, not a sign of failing components. There are several known maintenance issues which are detailed in the link | As a first generation VGA monitor, the 8500 series has its shortcomings. A dot pitch of 0.41 makes the display fuzzy and monitor dims noticeably when drawing light-colored screens, though this is considered a design flaw, not a sign of failing components. There are several known maintenance issues which are detailed in the link to the IBM 8512 page on repairfaq.org (see [[#Related Links]]) | ||
===Power Supply Failure / Squealing / Clicking=== | ===Power Supply Failure / Squealing / Clicking=== | ||
Revision as of 17:32, 9 February 2022
| This device is in the WorkNeeded:OriginalParts category because it was flagged as missing information on the original parts. It may have replacement parts listed but those cannot be assumed to be identical to the originals. If you have a list of the original parts, please feel free to add them by copying the relevant table from EditorsToolbox:Tables | 
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| This device is in the WorkNeeded:ReplacementParts category because it was flagged as missing information on replacement parts. If it has the original parts listed you may be able to search for replacements using the parametric searches available from parts distributors. If you have or make a list of replacement parts, please feel free to add them by copying the relevant table from EditorsToolbox:Tables | 
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IBM 8512 VGA Monitor
| Preliminary Information | |
|---|---|
| Release Year | 1987 |
| Leak Risk | Medium |
| Batteries | None |
| Mounting Technology | Through Hole |
| Capacitor Types | Aluminum Electrolytic, Tantalum, Ceramic, Polymer |
| Destructive Entry | No |
| CRT Guides | |
| General Information · Repair Cautions | |
IBM's first generation VGA display released with the IBM PS/2 computer line.
Known Issues
As a first generation VGA monitor, the 8500 series has its shortcomings. A dot pitch of 0.41 makes the display fuzzy and monitor dims noticeably when drawing light-colored screens, though this is considered a design flaw, not a sign of failing components. There are several known maintenance issues which are detailed in the link to the IBM 8512 page on repairfaq.org (see #Related Links)
Power Supply Failure / Squealing / Clicking
Causes
- Blown filter capacitors (line or transformer side)
Solutions
- Replace line filter capacitors in power supply.
- Replace larger capacitors
- Consider complete recap.
- Use low-ESR capacitors at output
Monitor Turns Red
Causes
- Neck PCB capacitor failure
- Output / driver transistors on neck PCB (see repairfaq.org link in Related Links)
Solutions
- Recap Neck PCB
- Possibly recap color gun circuitry under EMF shielding on main PCB
Disassembly Notes
When replacing caps located under the EMF shielding, be careful to note capacitor heights for the taller capacitors (C340, C354, C357) if the EMF shielding is to be retained. Experience suggests EMF shields may not be necessary for reliable operation - YMMV.
Original Parts
Main (9979800001) and Neck (9979800002) PCBs
NOTES:
- All capacitors listed below are through-hole mounted aluminum electrolytics.
- All capacitances are micro Farads (uF).
- Capacitors C100 - C400 are located under the EMF shielding (near RGB pots)
- Capacitors C400 - C700 are located in the horizontal / vertical control circuitry (middle section of board to flyback)
| RefDes | Qty | Capacitance | Voltage | Diameter/Size | Temp | Series | Notes |
|---|---|---|---|---|---|---|---|
| C115, C215, C315 | 2 | 0.47 | 50 | ||||
| C113, C213, C313 | 3 | 1 | 50 | ||||
| C106, C206, C306 | 3 | 4.7 | 25 | BI-POLAR | |||
| C108, C208, C308, C352 | 4 | 4.7 | 50 | ||||
| C101, C201, C301 | 3 | 47 | 16 | BI-POLAR | |||
| C104, C111, C114, C204, C211, C214, C304, C311, C314 | 9 | 47 | 16 | ||||
| C350 | 1 | 100 | 16 | ||||
| C356 | 1 | 100 | 16 | ||||
| C353 | 1 | 100 | 25 | ||||
| C340, C354, C357 | 3 | 470 | 25 | ||||
| C503, C620 | 2 | 1 | 50 | C620 not present on rev 08 | |||
| C753 | 1 | 1 | 250 | ||||
| C412 | 1 | 2.2 | 50 | ||||
| C401, C516, C556, C601, C602, C751 | 6 | 4.7 | 50 | ||||
| C355, C413, C515, C557, C752 | 5 | 10 | 50 | C557 not present on rev 04 | |||
| C537 | 1 | 22 | 160 | ||||
| C545 | 1 | 22 | 250 | ||||
| C408 | 1 | 33 | 16 | ||||
| C622 | 1 | 33 | 25 | ||||
| C554 | 1 | 33 | 35 | ||||
| C555, C604 | 2 | 47 | 25 | ||||
| C405, C414 | 2 | 100 | 25 | ||||
| C425 | 1 | 100 | 35 | ||||
| C534, C609 | 2 | 220 | 16 | ||||
| C552 | 1 | 220 | 25 | ||||
| C416 | 1 | 330 | 35 | ||||
| C514 | 1 | 470 | 25 | ||||
| C428 | 1 | 470 | 35 | ||||
| C550 | 1 | 1000 | 25 |
| RefDes | Qty | Capacitance | Voltage | Diameter / Size | Temp | Notes |
|---|---|---|---|---|---|---|
| C853 | 1 | 1 | 100 | |||
| C804, C814, C824 | 3 | 1 | 250 | |||
| C806, C816, C826 | 3 | 2.2 | 315 | |||
| C842, C844, C850 | 3 | 10 | 100 | |||
| C843 | 1 | 47 | 16 |
Replacement Parts
Basic PCB Name
| RefDes | Qty | Compatible Part Number | Order Links |
|---|---|---|---|
| Digikey |
If parts are not available or different selection is preferred, you can use the values in the Original Parts section to perform a parametric search.
Kits
- Digikey BOM: https://www.digikey.com/