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486DX266: CMOS Battery and PC Speaker

After building this machine, I am finding that I am losing my BIOS settings each time I pull the plug at the wall. The original motherboard owner/restorer replaced the onboard battery with a coin cell socket, but it seems that the 3v cell I put in there isn't powerful enough to keep the charge!

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PC Restorer has a great article on CMOS batteries and the best point to take form their site is that most BIOS' need 3.6-4.5v to keep their memory.

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In the picture above, you'll see the 4-pin header for an external battery. Pin 2 is missing. On this motherboard, pin 1 is positive and pins 3 and 4 are ground.

Using a standard 4-pin header plug from Jaycar, I wired up a 4-cell AA battery pack, but only used 3 cells. This required soldering new wires to allow current to flow between only three of the batteries.

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With this all soldered, a quick test with the multimeter saw ~4.89v on the pins... which was more than expected, but an acceptable value.

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Installation was a breeze and testing proved that my BIOS settings finally held!

PC Speaker

The case I have installed this machine in didn't have a PC Speaker installed by default. Therefore I used the same 4-pin header to rig up an 8ohm speaker from Jaycar. There's no real need to worry about the polarity here as it's just mainly beeps and boops. Who cares which way the diaphragm shifts?

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On first boot, the machine-gun noise of RAM counting up was music to my ears!!

Filed under: Retro No Comments
16Mar/170

486DX266: Rebuilding my childhood PC

I've been itching to do this for a while. There've been some nice 486 motherboards coming up on eBay, but I haven't been in the position to get them until now. A Hippo VL+ board appeared and, although it had suffered battery damaged (and been repaired!), it was a bargain for the price. I've always wanted to tinker with the VESA Local Bus and now was my chance. I did have a VLB board back in the day, but hardly knew what it meant.

Base Components

This was to be a completely build-it-yourself project. Each item was individually selected from whatever came on offer via eBay. First up was the motherboard with 4mb of RAM and that all-important exactly-what-I-wanted 486 DX2/66 processor.

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You can see where the previous owner has repaired a leaking CMOS battery. The wiring has been well-done and is all hot-glue-gunned down. The coin cell slot is in its place, but I seem to still be getting CMOS battery low issues. It could be that the coin cell battery is only 3v when the CMOS needs 3.5v+.

Next up was the VLB controller card. These full-length half-height cards provide two IDE channels, two floppy drives (via one cable), 2 com ports, a game port and a printer port! The HDD activity LED is also attached to this card.

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Finally, the all-important video card. I happened across a cheap S3 86C805i VLB card. It has expandable RAM of which I'll try and fill later on.

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There are only three slots where these cards fit into. You'll also find that they are named as to their purpose! There are two 'master' slots and a 'slave'. For those playing at home, the 'master' slots allow cards that support bus mastering; where the card will receive direct information rather than data via the CPU, and have it's own processing power on-board. The slave slot is for cards that don't support bus mastering but want the additional bandwidth of the VLB.

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A quick trial assembly then took place. Be really careful when doing this on a flat surface! The end plates have tabs that are meant to slot into the case when the board is mounted... when not, they will simply push into your desk/table and pressing further is strongly discouraged!

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Housing

I picked up a AUD$1.00 ATX case from eBay. Yes. ATX. It'll never work, you say? I have previously already put a 386 in an ATX case, but that was whilst keeping its old AT power supply and having the power cord hanging out the side. Not very neat. This time around we're going to do things differently.

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Meet the case, creepy photo, right? It's full ATX... soft buttons and all. It even has an ATX power supply.

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How do we possibly use an ATX supply with an AT motherboard? With an adapter plug! This beauty was found on eBay for the handsome sum of AUD$5.00.

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So, simple mounting of the board ensued. Turns out the back plane is riveted into the case; annoying as previous cases I've dealt with usually allow this panel to be removed for easier motherboard mounting. Either way, the motherboard was mounted in and the adapter was hooked to the power supply.

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The other end was then slapped onto the board itself. Remember with AT plugs, keep the black wires together!

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Great ... so ... now what? The front panel can be rudimentarily hooked up. Reset, Power LED, Turbo LED? and that's it.

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The case was stood up, all cables checked and arranged neatly so as to not cause any shorting issues and then a monitor was connected. The power supply was then jump started. This is simple: simple join the 'dangling' green and black wires together.

It worked!

ATX case + power supply without an ATX motherboard

Here's the trick you've been waiting for. The power button on the front of the ATX is momentary. This means that when you press it, power is conducted for only the timespan until you let go. So, if we hooked this up directly to the green/black wires from the power supply, we'd need to hold/tape the button down until we were done with the computer... not very handy.

Because of this, we're going to use a relay to latch the required power supply wires. The basic idea is that we'll put the momentary button on the green and black wires from the power supply and then latch those down when power starts to flow. To do this, we'll use a drive power plug which will supply us with 12v/5v when we've pressed the power button. This power feed will then latch a relay that'll latch the power button. When we let go, the power will continue as the relay will emulate an extended press!

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So, apologies for the crude diagram, but that's the basic idea above. The relay is a 12v single-pole-double-throw and therefore has power, common, normally-connected and normally-open terminals. Power is used to actually throw the relay and is fed from the 12v drive power. Normally-opened isn't used as we only care about the actuation of the relay. The normally-closed side is therefore put in parallel with the power switch. When the switch is pressed, the relay fires and reinforces the power button.

The best part? It worked perfectly! The machine came on and I played A-Train. The problem? Hitting Reset did as expected... it reset the machine, but I had no way of turning it off without yanking power cables! I originally hoped that reset would trip the drive power and reset the relay; alas it turns out that the 12v stays constant. We therefore have to amend the circuit to allow powering down the machine from the reset button.

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Here, we've taken the reset switch off the motherboard and used it for an off switch. This means that the machine is power-for-on, reset-for-off. It makes sense... doing an actual reset will just mean hitting reset-and-then-power instead of just reset.

In the above diagram, we've used a second identical relay to interrupt the power supply of the first relay. To do this, we've fed one of the coil power feeds of the first relay through the normally-closed line of the second relay. This means that, when the second relay is not active, the current can flow through it to the first relay. Exactly as we want, as we don't want to do anything until the reset button is pressed.

When the reset button is pressed, it'll actuate the second relay and break the current to the first relay. This will, in turn, break the latch on the power switch and the ATX supply will shut off. Pressing the power switch again will re-latch the power and we'll be up and running again.

Actually building it

I used some crappy veroboard and a spare drive power plug that I had laying around. Hot glue then helped to insulate everything. Note that in my initial sketch, I was trying to be overly-tricky and had the 5v power fed through the other side of a DPDT really. This is redundant and really not needed!

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The final product worked perfectly!

Filed under: Retro No Comments
10Mar/170

Compaq Deskpro 386s/20n: RH Linux 5.2

I had tried to load BSD on this thing a while back, but didn't get very far. Recently I found an original boxed-set of RedHat Linux 5.2 and, to my surprise, the system requirements had this machine's specifications as the recommended minimum! I was therefore very happy that I had previously managed to find an 8mb RAM upgrade for this machine.

Installing a big-enough IDE disk

The 40mb Conner that was in there was never going to suffice. I'd previously installed a 256mb 'SSD' disk, but this wouldn't do either. Instead, I'd recently picked up a 1.2g IDE from the flea markets, which won't work straight away with DOS (Use AnyDrive for that), but will work fine in Linux as the bios specifications are bypassed.

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RedHat 5.2 comes with 3 installation CDs and a boot disk. I had previously built a PIII-500 and installed RH from these disks, so I knew the software was in working order. It was whilst installing RedHat on that machine that I saw that it may well also work with the 386. Just for fun, I slapped the boot disk in to the 386 and quickly got the LILO boot loader. After a short while I was in the installer, only to hit my first hurdle: the installation obviously needs CD access! The Compaq has a very slim case, so there was no option to install an internal drive. I'd previously used my Microsolutions Backpack Parallel Port drive under DOS on this machine, so I thought I'd give it a go with Linux.

RedHat comes with a bpcd.o driver for this device but I couldn't get it going! I tried all permutations of configuration for the driver (linux bpcd=0x3bc as a LILO boot command and also bp_base=0x3bc during install), but nothing would get the drive to spin up! Booting into DOS, I found the correct address to be 0x3bc... but nothing would make it work.

Turns out I'm not the only one.

Installing over the network

I could choose FTP from the boot disk, but it them asked for a supplementary disk? I only had CDs at this point, so I couldn't continue.

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The next best option was NFS and so I started searching for NFS Servers on Windows, as that was the easiest and closest machine available to host the required files. There were three options: FreeNFS, winnfsd and nfsAxe.

Of the three options, nfsaxe was the only one I could get working. I had copied the RedHat CD to a folder in Windows and pointed nfsAxe there. I then mounted it on the RedHat installer on the 386, but it quickly failed trying to find files.

Looking at the logs on the 386, I could see it looking for 'RedHat'. Looking at the folder on Windows, I could only see 'REDHAT'. I knew that Linux was case-sensitive, so I realised that this wouldn't work. Once in the RPMS folder, I then saw that all filenames were in capitals and the old 8.3 format!

Oh shit... Windows is reading the CD as ISO file format and not Linux... I couldn't work out a way to get around this natively in Windows. Instead, I had to copy the files from a Linux machine into the NFS server on Windows. As previously mentioned, I'd set up a Linux machine on another box, so I booted this up and mounted the NFS share on Windows. It all worked and I started copying over the CD's contents! Here you need to realise that nfsAxe has a 30-minute trial period! If it detects file activity on the NFS server, it'll start a stopwatch and shut the server down after 30 minutes.

So, the experience was terrible and took quite a few attempts, but the CD was copied over to Windows. I then booted the 386 and pointed it to the NFS. It found the files!! Installation started and showed an estimated time of 1.5hrs to install. Hah. That wont work... the NFS server, even with a freshly timed restart will only stay up for 30 minutes.

Using a virtual machine?

TurnKey Linux has a fileserver image that, when spun up, provides a 'NAS' style linux machine. I downloaded the ISO, set up a VM on Hyper-V and got it going pretty quickly. You'll need to run service nfs-kernel-server start to start NFS as it's not enabled by default. The exports are all configured, so you can test it locally with mount localhost:/srv/storage ./test and see that you can loopback to yourself. I then mounted the CD and copied the guts into that folder.

Meanwhile, the 386 couldn't see the share. I tried disabling nFS v4 and then NFS v3 (at this point I couldn't even loopback mount as V2 is not supported!) but nothing worked. I was worried that it was a network bridge issue between the physical machine and the virtual. I had the NIC set to the physical adapters 'bridge' in Windows, but ... meh ... it hated me!

Enabling an NFS share on 'Workstation' Redhat

What next? Let's set up a real physical NFS server on that RedHat 5.2 machine I mentioned earlier. I'd done the 'workstation' install, so NFS wasn't up and running by default. Firstly I edited /etc/exportfs and added /mnt/cdrom *(ro) as the first export. A reboot just threw 'permission denied' on the 386.

Trying to mount this as a local loopback threw permission denied also? Did that mean a firewall? Folder access? Where am I actually denied? I really had no clue at this point as I thought I'd done everything as needed. NFS seemed to just be a very built-in thing for Linux and should just-work(tm).

If no options are passed to the /usr/sbin/exportfs command, it displays a list of currently exported file systems. Ok, let's check... no.. let's not check... the exportfs only accepts -a. Ok... stuff it... time to install a real version of the OS.

After re-installing RedHat 5.2 in 'Server' mode, I type net *tab* *tab* and to my surprise: netconf appeared...

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Hah! I wonder if this was there in 'workstation' version? We'll find out once the 386 is installed. I set /mnt/cdrom as an export and ticked all of the dangerous options. The bloody thing mounted locally and also worked on the 386.

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Yeeey... activity on the RedHat 5.2 Server CD. We could finally get this installation started... and completed...

5 hours later...

The installation completed and I was prompted to remove all boot media and restart. I did as requested and... hahaha... what the hell... the screen just kept scrolling the magical number 04. The picture below is funny as you can actually see the redraw/scroll at the bottom edge.

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Seems someone else has had this problem also. I let the installer configure the disks, so maybe it got the bootloader wrong.

Hah. Nice. So I then re-installed using 'custom' and also opted to make a rescue boot disk. I chose to install LILO in the MBR and got the same screen as above. Fortunately, the boot disk loaded the hdd perfectly.

It made it to the console... but it took around 6 minutes to boot. I then bit the bullet and started the x-window-server.

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It actually failed to load anything past the xterm. The dock to the right nearly loaded, but bombed out and disappeared. The xterm was functional... slowly. I checked top and saw that there was swap memory, but no physical. This poor thing would be thrashing the page file and not getting anywhere. So, although I already knew the answer, I tried to launch netscape-communicator. No chance... it froze.

Therefore, RedHat will run! But don't expect X11 with 8mb of RAM. Use it for ... a file server? Am sure it'll serve up the web also. Good luck.

Filed under: Retro No Comments
9Mar/170

Using your Sega Dreamcast on a new TV

I had recently been playing my Dreamcast on my old TV, which had a VGA input. Using the DC VGA BOX, I had VGA and audio output from the Dreamcast and all worked perfectly.

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In the last fortnight, I've picked up a brand new Sony KD49X8000D and it doesn't have VGA input! HDMI, Composite or Component... they're the options. It was time to browse eBay for options.

VGA to HDMI

Without doing any research, or reading the product description, I jumped straight in and purchased a cheap straight-through VGA to HDMI cable.

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It was never going to work. It seems to only be for projectors where they transmit random signals via VGA plugs. Don't expect that an analogue VGA signal can just magically transform inside a cable to HDMI.

VGA to RGB

I then saw this cable at trash and treasure last weekend. It's got VGA at one end and RGB on the other. I thought that it might be component, so I paid the handsome sum of $2 to test it out.

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I'd forgotten to test it, but just read online that it also wont work. The description of a similar cable here indicates that this is for specific projectors under specific circumstances.

MINI VGA2HDMI Adapter

I resorted back to eBay and looked for an 'active' adapter. I found this one, cheap, on eBay and thought I'd give it a go.

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In the end, the cabling is a nightmare as there aren't nice small VGA cables available.

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Super simple to connect. But it didn't work first off. Someone else has made this item work before, so I must have something wrong with my configuration. It could also be that my TV doesn't support the resolution over HDMI.

Uhmm... nope.... I then tried another HDMI cable and realised that this one seated in around 2mm further! And worked! Switching back to the other HDMI cable saw it working too: it just needed a bit more of a jab to make proper contact with the converter. Note! These converters are cheap and cheerful, so do be careful when hooking them up.

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Check that out... you can see the TV LED at the bottom... that's the initial picture at 1:1 640x480. Very clear!

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And then scaled... looking great. Sounding o..k.. a bit scratchy at times. Will check my headphone cable between the devices. Anyway. Success!

Filed under: Retro No Comments
3Feb/170

NEC PC-8201A Portable Computer – Black Screen

Here's a new acquisition. It's an all-in-one portable machine from the early 80s. It was sold cheaply as non-working and, indeed, it non-works.

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I hadn't realised how big these things were!? I was expecting something around half the thickness and maybe 60% the width/height. It's actually a really nice machine and I do like the form-factor. This item came quite scuffed and 'used'. All to be expected and nothing to worry about. I purchased it since they seem to have a great array of I/O ports and programmability. They run Microsoft BASIC off-the-shelf and have 32kb of storage.

Initial Inspection

First signs of tear-it-down-before-turning-it-on showed up as soon as I checked out the battery pack. The batteries weren't in there, but there was a LOT of corrosion. The circuit board in the battery pack even seemed to have components missing? Did they corrode and disintegrate away?

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After a good scrub, all was much cleaner... I had already decided to pull the main machine apart first though. Corrosion has a magical property of travelling inside metal (just like electricity) and conquering whatever it can get its green rusty mits on.

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Of course, it had spread. The terminal and battery pack isolation switch were the main victims. Fortunately, it didn't seem that the tracks or other components were affected?

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Both Isopropyl alcohol and cleaning wipes were used to clean up the board. Light scrubbing was also required in the hard to get areas.

Powering it up

After all the cleaning and soldering above, it was time to bite the bullet. I found 4 random AA batteries and slotted them into the pack. My multimeter showed 6 volts, so I slapped it in an gave it a go.

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Flicking the power switch on the side gave no response. I had read online somewhere that the first thing to check is the "Back Up Power" switch. I initially thought this meant "use the internal battery", but it doesn't. It actually means "use the batteries you've just inserted". With this switched over, the power switch on the side saw the unit come to life... well... there were at least a few electrons flowing.

Black Screen Of Death

For now, we're going to disregard the damage to the LCD. you can see that something pointy has taken out a sizable area of the screen... but 95% of it will still be usable prior to needing to replace that.

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After the power switch was flicked, the screen produced the result you see above. Trouble-shooting this is pretty straight forward. As per the instructions here, press Enter, then type BEEP and press Enter again. If you get a beep, then your mainboard is fine and your screen is crap. My mainboard was not fine!

The next bit of googlin' found this result on diagnosing and repairing a black screen. Turns out one of the 245 chips was only half-functioning. I love that the author also found errors in the service manual. Either way, the repair-man found a defective IC and replaced it... as that I had no way of determining what was defective, I started replacing everything.

Component Shopping List

From the service manual, I found the following replaceable chips at my local electronics store.

Original Chip Jaycar's Version
40H139 : U1, U53, 74HC139 (ZC-4848)
40H386 : U51 74HC86 (ZC4835) IS NOT PIN COMPATIBLE!
Jaycar therefore doesn't have a replacement.
40H245 : U13, U42 74HC245 (ZC4870)
40H373 : U15 74HC373 (ZC4874)
40H367 : U??, U?? 74HC367 (ZC4872)
40H138 : U2, U3, U4, U5, U6 74HC138, but Jaycar doesn't stock it!
40H175 : U11, U12 74HC175, but Jaycar doesn't stock it!
603 Transistors BC547?
115 Transistors BC556/560?

Note: The above list is a work-in-progress. I'll update this as I continue identifying and replacing parts.

Find and Replace

Removing components from PCBs is always a challenge. Even with the best solder-sucker, you can still have a very hard time making sure every pin is free. In the end, as long as you don't need the existing IC, snipping legs and then removing those can be a much better option.

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I've used sockets for each IC I'm putting in as well... I've no idea if this whole board is pointless, so I'd prefer to waste a socket more than an IC. I started with the 245 that was mentioned above and got nowhere... still the blank screen... I then replaced a 367 and had no luck either. This was really a crap-shoot and a very slow process. From here I thought there had to be a better option... so I consulted the service manual.

Troubleshooting via the Service Manual

I really should've started here when diagnosing the issues in this machine but, when I had first read it, I saw the word 'Oscilloscope' and got scared off. I don't have one of these, so I didn't think to pursue this area of investigation. I had since come back to it after realising that replacing each of the ICs was going to take a REALLY long time.

On page 54 you actually get to test each of the pins on the CPU itself. It indicates the pin and the expected voltage. Note that the CLK pin is meant to flip/flop and this can't be seen from a multimeter. All you can really look for is a 'half' voltage, as the flicking effectively provides 50% 0v and 50% 5v totalling 2.5v. All of the pins on my CPU came up OK as per the values stated!?

From page 85 of the manual, you get instructions on what voltages are meant to be seen from the power supply board when the computer is powered on. All but one of these turned out to be OK. Pin 10 was meant to be greater than 7.5v, but mine was only just over 7.0v. The manual then tells you that U2, Q16, C1, or D7 of power board are bad. Ok... this is good! Let's replace everything we can.

Something weird happened next. I didn't have the required components to repair the power supply, so I tidied up the desk for the evening. As I put the machine back together (aka. placed it into a pile of loose parts), I accidentally toggled the power switch.

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Wait... what... we've got movement! The screen displayed a bunch of random rubbish. Sometimes a cursor, other times a heap of LOAD statements and at one point I could even type in a command... I didn't get a BEEP though.

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The only thing I can attribute this to is that the power supply board received attention. I had shifted the caps around and also wiggled transistors. Maybe some of these had faulty solder joints? I should've measured pin 10 again here, to see if it all happened because of a 7.5v reading. Unfortunately, I couldn't get it back into such a state. I went ahead and purchased parts to fix the power supply. Unfortunately, I couldn't find the correct transistors at Jaycar to replace Q16 as per the instructions above.

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I replaced all I could but still couldn't get the machine to do what I wanted. Actually, as I first started tinkering, the display of crappy text was satisfying. Towards the end, I hardly had a jumble of pixels. Toying with the ROM did seem to help... I wonder if the chip or socket area was damaged? Maybe static had fried it? Out of desperation, I attempted to swap some transistors around on the power board. Maybe that Q16 was the final issue. I did note that the 7.5v was still very intermittent. It didn't quite appear when the machine was half-working and only appeared at other random times... maybe the board was pulling too much current due to other issues and therefore was never actually going to let the power supply do it's thing?

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Playing switch-a-roo with transistors revealed some information on the power supply. Swapping the 603s between Q2, Q16 and Q3 made either the speaker click, the relay click or nothing at all. To me this meant that one/some of the transistors were faulty. It didn't matter which as I didn't have a replacement. Trying to find actual 603s was impossible but, using the cross-reference tool here, I have just found out that BC556s are a valid substitute.

Or are they? Let's rewind a bit... I assumed that the transistor was a 2SA603... but it actually can't be. Using this complimentary transistor table, it seems that my transistors are 2SC2603 and 2SA1115. It would make sense that one was NPN and the other PNP. I therefore need BC547s (although they seem to be rated 100mA less and the pins are reversed!) for the '603' and BC560s for the '115'. Unfortunately, Jaycar doesn't have 560s, so I'll choose 556s instead, which are just have a higher voltage tolerance and a lower amperage. I might also order the correct components from eBay.

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So, transistors... turns out that on page 108 of the service manual, the components are listed. I was totally correct on the transistor model... well, after I corrected myself. I therefore bought 20 of each from Jaycar.

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Of course, I jumped the gun and didn't correctly review each component. The pins weren't backwards, they were actually out of order!

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So, with the legs crossed, just enough, the order of the pins could be adjusted...

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Whilst replacing the transistors, I also replaced the capacitors. Of course, one had to have exploded. Happened to be the 33uf that assists with the -5v output. I assume it's a cap that stabilises the voltage. I simply used solder to bridge the damage.

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The results started off erratic... but then seemed closer to rendering a real screen?

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And then it happened!

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Keyboard didn't work.. screen was frozen... but shiiiiit... that's the actual main menu! I actually nearly have a real computer! I then replaced all the signal diodes on the power supply.

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With the diodes replaced, the keyboard worked! Note that at this point in time, the board relay was not actuating on power on. It had previously, intermittently... but doesn't seem to be essential? Either way, as above, the menu worked and BASIC loaded. Unfortunately, once loaded, BASIC was useless with a screen full of junk. Any keypress resulted in Memory Full and a system beep.

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I opened up TEX, typed in the obligatory sentence, pressed enter and the machine froze up... the work continues!

One step forward...

And then back to the beginning. I did something stupid over the weekend. On Saturday night I placed the ICs I had purchased over the top of the ICs they were to replace, so as to be able to see what ICs I still needed to replace/purchase. With these piggy-backed loosely, I closed the machine and put it aside.

Forgetting that I'd done this, I attempted to boot the machine the next morning... It presented the infamous black screen and not much else. As I shifted the machine to the center of the workbench, I heard parts move and instantly remembered what I'd done the night before. What a bloody waste of time I am; forgetting that I'd left the ICs in there and hence possibly doing all kinds of damage.

For the life of me, I could not get the machine back to where I was on Saturday afternoon. Such a let down! The only real goal was to hope that I'd only damaged mounted items and not the new items I'd purchased... then again, I could just re-purchase as I'll socket all the ICs.

IC Replacement

Solder suckers are fun, but Desoldering Braid is the best thing since sliced bread! Once you've removed the IC+legs from the mainboard, you'll find it quite difficult to remove the solder from the holes. Desoldering braid does this for you and does it quickly and cleanly. All you have to do is unreel enough to cover the hole and then press your soldering iron directly into the center of the area. The chemicals in the braid them somehow manage to attract the solder!

If it doesn't work the first time, then re-apply solder first. Only use the braid on holes that are full. If there's a gap, then the solder wont jump, it'll only flow! Also, the longer you hold the soldering iron there, the better. Watch as the solder flows into the braid and lift when it stops flowing up.

After removing the TC40H386P, and thinking that the 74HC86 was a replacement, I worked out that it wasn't. A hack was employed to get around this.

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I lost a lot of faith with hacks like the above. Regardless, I ended up replacing half the chips on the mainboard and didn't get anywhere... it was time to wait for the oscilloscope to arrive.

Filed under: Retro No Comments
10Jan/170

IBM NetVista M/T 6825-M23

This poor machine was about to be sent to the recycle center... so I salvaged it and downgraded it. Getting Windows 98 to run was a challenge!

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Windows 98 doesn't like more than 512mb RAM

Found this out the hard way... the installer would boot the CD, start installing and then fail randomly throughout the install. Once it actually made it to the first reboot and then failed to reboot. It threw an error on the dos prompt of which I failed to record. The machine had 512+512+128 in there (which was an odd combo anyway) and I reduced it to just one 512 stick. After this is worked fine.

Sound Drivers

I downloaded and installed around 20 different SoundMax drivers and had absolutely zero luck. 1 month later (when I finally had a use for the machine) I came back to get the audio going; I needed a full multimedia experience.

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I checked out the motherboard and found that it had a AD1887 chipset... turns out that this was made well after the Windows 98 era and therefore finding drivers wasn't easy.

Fortunately, Totempole posted the same issue in the vogons forums! Unfortunately, his links are dead. A little googling found the correct file (although it stated it was for Windows 7 or higher?) which worked a charm! Here it is for safe-keeping: SoundMax AD1887 Driver for IBM NetVista Desktop Workstation (d63z32us.exe).

Note that if you want DOS Sound to work, then you need to specifically enable it.

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And then you can play awesome games!

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NVidia AGP Riva TNT2

This machine came with this card in the AGP slot. There's no on-board graphics in this machine.

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It seems like 81.84 was the final NVidia driver to support Windows 98 but I somehow managed up with 71.84_win9x_english.exe installed. Display Properties shows that this card is an NVidia Vanta? Never heard of it. Running at 1920x1080 in Windows 98 SE is pretty random.. but great for the next trick.

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Now to start producing Director 5 movies for this project and ... playing A-Train.

Filed under: Retro No Comments
30Dec/160

A-Train III SV – Super Famicom

Christmas always provides an opportunity to raid the childhood cupboards. My brother had once owned a Super Nintendo and I was sure it was still in the house somewhere.

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I was looking for it because of this...

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Yes, they made a "Super Version" of A-Train III for the Super Nintendo. Well.. that is actually where I am wrong... it's for the Super Famicom and this is what I got when trying to run it...

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Fail... to emulation we go! A quick google of "Take the A-Train" and "SNES" resulted in the acquisition of a relevant ROM (I own the cartridge, so this is OK, right?) and ZSNES.

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From above, you can see everything worked fine. The game jumps through two menus: the first allows you to chose a previous game, or start new, and the second lets you configure a new game. I'll explain all this soon. I'm now waiting for a USB SNES controller to play this properly.

Note that when you are thrown into the map, the whole world rotates smoothly. The developers seem to have used every part of the SNES graphics hardware to produce very smooth translations and sprite effects. Even the music and sound effects are fantastic! This seems to be very different from the standard PC A-Train III.

30Dec/160

A-Train MD – Sega Mega Drive

Whilst continuing my quest to acuire every version of A-Train, I came across the
Sega Megadrive version on eBay. Never one to resist, I did a quick little bit of research to see if it'd work on a console over here once imported. I stubmled across the following eBay page regarding NTSC Megadrive games on PAL consoles and was assured that, although there's a cartridge shape difference, the games could be made to work.

I then found an AtGames Megadrive Clone (that link is to the Genesis, can't see the mega drive on their site?) for dirt cheap on eBay and everything arrived in short order. I disregarded any sound advice on the clones and just bought it. Here's a brutal review of this console. Update: It actually might be that this cartridge wouldn't work on a real Australian Mega Drive and that this clone saved me and allowed me to play the game.

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As you can see, the game came boxed and in great condition. An interesting fact: the game cost 8700yen at time of release! The instruction manual is huge and I'll need a lot of help to get through it. Fortunately the game fit perfectly into the Mega Drive Clone.

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And the million dollar test...

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What's USA doing there? Time to work out how this game differs!

19Dec/160

A-Train III – PC Engine

After finding A-Train for the MSX, the Famicom, the Amiga and the Megadrive, I googled a little more and found out that version 3 was released for the PC Engine. Of course, this is the actual version three, not I or II that were released on Japan earlier. It's on par with the first A-Train to be released to the west. I found a copy on eBay and couldn't resist!

PC.. Engine?

Yeah, this was a video game console released by Hudson Soft and NEC in Japan. It was later released in the west as the TurboGrafx-16. It was released at around the same time as the SNES and Sega Genesis.

This console made history as the first to have a CD-ROM expansion and then an inbuilt CD-ROM when the Duo was released. The console kept evolving and a second version of the PC Engine CD-ROM format was released. They named it Super CD-ROM². Older machines could be 'upgraded' via a System Card (HuCard) to be able to read the newer CD format.

Multiple variations of the PC Engine were built, check out the wikipedia link for more information.

A-Train III for the PC Engine

This version of A-Train has great sound effects and utilises the CD Audio for background music. It requires the Super CD-ROM² System Card to boot.

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I don't actually have a PC Engine, so I did a little investigation on how to emulate it. Turns out that Magic Engine needs to be purchased and mednafen needs a serious amount of configuration work to boot off a real CD.

Running with Ootake

This couldn't be easier... download Ootake from here and install it. You'll find an icon on your desktop once installed; double-click this. Initially you're greeted with a disclaimer. Insert your Game CD and then choose CD-ROM. You'll need a system card image to boot into the machine as a Super CD-ROM², a little googling should get this for you without too much effort. Once you've selected the file, hit OK...

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Now to work out how to play the game ... Ootake emulates the PC Engine Mouse and this game happily uses it, so it shouldn't be too different from the other versions!

Filed under: Retro No Comments
4Dec/160

Compaq Deskpro 386s/20n: CMOS Battery

So, I totalled the previous motherboard and found a new one online. This one was the 16mhz version (the original was an SX-20) and had a different component layout. At the same time, I also purchased 8mb of RAM (Parity SIMMs!) and a 'new' Dallas Clock Chip/Battery from eBay.

After slapping it all together, the RAM counted up nicely and I could get into the setup as per usual. I configured the HDDs and then saved the settings and rebooted. Instead of working fine, each reboot presented me with the 162-System Options Not Set-(Run Setup) error. No amount of configuration would work. Everytime I continued and went into the setup, it would remove the HDD configuration. I could see that the BIOS wasn't even searching for the HDDs.

This was weird as the system was more-or-less configured back to a standard Compaq factory-issue. Everything was in good nick. I had a hunch though; maybe that Dallas Clock Chip from eBay was actually already dead!? The fact that I hadn't powered down the system meant that the configuration should have applied; this didn't seem to be the case!

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I replaced the battery as per the previous one that I replaced (I actually ended up using the original one on the motherboard for the other 386 I picked up recently.) With the hack in place, the BIOS configuration saved and the HDDs were detected and ... the world was a happier place!

So... if you have a dodgy old Compaq Deskpro like mine: MAKE SURE YOU HAVE A GOOD CMOS BATTERY!