IBM PC Convertible
http://ohlandl.ipv7.net/5140/5140.html
Computers in Collection
General Notes
Original power jack is a Hosiden HEC, number 0470-01-250 or equivalent (reference, page B-3). Center pin is 2.35mm, and is the positive contact. Mating plug is shown having 9.5mm length and 5.5mm outer diameter. The machine’s case has a 10mm hole for the DC adapter, so take care to buy a DC plug with a plastic molding of less than 10mm to ensure it fits into the hole. Frustratingly, the options I’m finding on Digi-Key don’t specify the plug housing’s diameter. I’m going to give the XP Power VEC50US15 DC adaptor a try (Digi-Key part 1470-3099-ND).
During reassembly, be sure the red power button is properly seated through the panel that covers the power supply. I didn’t take care to do this, and the power button was wedged into the “on” position, which naturally made it hard to turn on the computer.
Floppy Emulation
I used a GoTek “SFRC922D” with FlashFloppy v3.29 inserted in place of the computer’s left floppy drive (drive A). The GoTek had only the S1 and JC jumpers installed, though I believe I overrode the JC setting in my configuration files (interface=?).
I had to adapt the 2x17 34-pin header to the computer’s 2x20 40-pin edge card socket using an adapter from a Teac FD-235. I had the adapter’s “OP” jumper set to connect pin 34 on both sides. It appears this adapter from @TubeTimeUS would do the trick and be a simpler and cleaner solution, too.
# FF.CFG
# IBM 5140 Convertible
interface = ibmpc
host = unspecified
pin02 = nc
pin34 = chg
# IMG.CFG
# I had to force my .dsk files to be read correctly by renaming
# them with a ".dsdd80.dsk" extension. I might've been able to
# rename them with ".img" instead and not had to use this IMG.CFG.
[dsdd80::737280]
cyls = 80
heads = 2
secs = 9
bps = 512
Reassembly Order
- Logic board into bottom tray.
- RAM expansion modules plugged in, snapped into bottom tray.
- Speaker connector attached.
- Place battery compartment, click in corner near modem port, install four screws.
- Mid-cover cable attached, placed over logic board, guide pins slotted into plastic pillar slots rising from bottom tray, floppy sockets installed into clips from the bottom, cover pegs nested into round cups on bottom tray.
- Push red power button from inside to ensure it’s sticking out as far as possible, then install power supply board.
- Install rear cover, install four screws.
- Install floppy drives, install four screws (gently, as it’s said the plastic cracks easily).
- Attach keyboard ribbon cable, insert rear edge of keyboard between floppy eject buttons and protrusions, drop front keyboard edge into place, then push front keyboard edge down to engage locking tabs.
- Open display connector latch, install display into connector, close display connector latch.
- Fold up the computer.
IBM PC Convertible, serial 26-3005553
Obtained from Sean@CCC, October 3, 2021.
System came with a CRT Display Adapter slice attached to the back.
No battery in the system, but somebody thoughtfully saved the battery connector and taped it inside the battery compartment.
Powers up using a 12V@2A power brick. Subtle light horizontal line on LCD, about 20% from the top. LCD contrast is terrible.
Inventory
Case
| Attribute | Value |
|---|---|
| Name | IBM PC Convertible |
| Manufacturer | IBM |
| Type/Model | 5140 |
| Part | |
| Serial | |
| Manufacture Date | |
| Manufactured In | |
| Input | |
| Source | 2021/Oct/03, Sean@CCC |
System Board
| Attribute | Value |
|---|---|
| Name | System Board |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Processor | Intel 80C88 (?) |
| Clock Speed | |
| Source | 2021/Oct/03, Sean@CCC |
Power Supply Board
| Attribute | Value |
|---|---|
| Name | Power Supply |
| Manufacturer | IBM (?) |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (1)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (2)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (3)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (4)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
Internal Floppy Drive (Left)
TODO:
| Attribute | Value |
|---|---|
| Capacity | 720KB |
| Source | 2021/Oct/03, Sean@CCC |
Internal Floppy Drive (Right)
TODO:
| Attribute | Value |
|---|---|
| Capacity | 720KB |
| Source | 2021/Oct/03, Sean@CCC |
Display Slice
| Attribute | Value |
|---|---|
| Name | CRT Display Adapter (?) |
| Manufacturer | IBM |
| Model | 4020 (?) |
| FCC ID | ANO52Y2684170 |
| Serial | A132M106821 |
| Case Markings | “Dec 19 1986” |
| PCB 1 Markings | “ECA30251” “PN2684161” “7550JB” “4051” “4086” |
| PCB 2 Markings | “ECA22148” “PN2684162” “7550JB” “4035” “4086” |
| Components | Hitachi 6J4 HD46505RP JAPAN HD6845P Toshiba TC17G022AT 0007 8649A JAPAN 2 x Toshiba TC5565PL-15 Motorola XE 1503723 (C) IBM 1983 8641A NM 2 x NEC uPC494C MALAYSIA 632K FOX 14.318180 MHz oscillator |
| Source | 2021/Oct/03, Sean@CCC |
IBM PC Convertible, serial 26-0300009
Obtained from Sean@CCC, October 3, 2021.
System came with a serial/parallel adapter slice attached to the back.
There was a hacked-together aftermarket battery in the battery compartment, which had been leaking a bit. I removed and removed the few chunks of battery residue, but it could still use a thorough cleaning.
Powers up using a 12V@2A power brick. LCD contrast is terrible.
Right arrow key was broken off, stem partially in keycap.
Retaining clip at the near right corner of the keyboard is broken off, broken piece is saved.
Left mid-cover pivot is broken off half-way in, broken piece is saved.
Floppy facades are cracked around outside screws, as I’d been warned. Not sure if I did it, but chances are good.
Right floppy’s left screw hole seems to be stripped, which suggests somebody ham-fisted (who isn’t me) was in the machine before, and might’ve done some or all of the damage I’ve found.
Inventory
Case
| Attribute | Value |
|---|---|
| Name | IBM PC Convertible |
| Manufacturer | IBM |
| Type/Model | 5140 |
| Part | |
| Serial | |
| Manufacture Date | |
| Manufactured In | |
| Input | |
| Source | 2021/Oct/03, Sean@CCC |
System Board
| Attribute | Value |
|---|---|
| Name | System Board |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Processor | Intel 80C88 (?) |
| Clock Speed | |
| Source | 2021/Oct/03, Sean@CCC |
Power Supply Board
| Attribute | Value |
|---|---|
| Name | Power Supply |
| Manufacturer | IBM (?) |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (1)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (2)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (3)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
128K Memory Card (4)
| Attribute | Value |
|---|---|
| Name | 128K Memory Card |
| Manufacturer | IBM |
| Part | |
| Serial | |
| Source | 2021/Oct/03, Sean@CCC |
Internal Floppy Drive (Left)
TODO:
| Attribute | Value |
|---|---|
| Capacity | 720KB |
| Source | 2021/Oct/03, Sean@CCC |
Internal Floppy Drive (Right)
TODO:
| Attribute | Value |
|---|---|
| Capacity | 720KB |
| Source | 2021/Oct/03, Sean@CCC |
Serial/Parallel Adapter Slice
| Attribute | Value |
|---|---|
| Name | Serial/Parallel Adapter (?) |
| Manufacturer | IBM |
| Model | 4015 (?) |
| FCC ID | ANO52Y6820792 |
| Serial | A132I132539 |
| Case Markings | “JAN 14 1989” “90113PC” |
| PCB Markings | “PN7396910” “CA30210” “6050JB” “60X5554” “EC A30225” “4888” |
| Components | 2 x 74ALS1034N 74ALS1035N National Semiconductor S+B8748 NS8250AWN INS8250AWN 61X6027 IBM 14 H41L00FQ *M* 10 08 1843.2 kHz crystal 2 x Fairchild uA1489APC 8816 KOREA Fairchild uA1488PC 8829 KOREA Motorola MPQ8002 I8843 Motorola K MJE150 29 8842 |
| Source | 2021/Oct/03, Sean@CCC |