The previous repairs ended when the power supply started to no longer provide enough current to boot the unit so i ordered the Univeral Power Supply from Reactivemicro.com as i’ve done earlier as well. That’s the best you can get for your money. It’s designed for all Apple II and /// models. The Apple /// can be so problematic so it’s more than good idea to go the roots of the possible problems and replace that power supply in the first place. That’s where it all starts anyway.
Also needed a replacement light bulb for the power light as it was burned off. The unit CAN be booted after pressing reset but that’s very annoying at least. Some references say the Apple /// won’t boot if the keyboard “power” lamp is burned, that’s simply NOT true. It does need just reseting the unit.
WHAT WAS LEFT TO BE REPAIRED OR TESTED?
-Ordering and installing the Universal power supply.
-Rubber feet replacement.
-Keyboard power light bulb replacement.
-Keyboard top cover repairs.
-Reparing video chips.
-Testing the keyboard layout with configuration file.
INSTALLING THE UNIVERSAL POWER SUPPLY:
I ordered the Universal Power Supply with the new DC-output cable from reactivemicro.com and it arrived in few weeks (with some +24% tax added). It’s very straight forward to install for the ///.
1) Open and remove the basepan (main logic board) and remove the power cable from the main logic board.
2) Open and remove the power supply from the enclousure.
3) Remove the original power supply and disconnect few cables as per instructions.
4) Install the new power supply PCB, the new power supply unit and attach the new cables as per instructions.
5) Screw the power supply back to the main chassis and attach the new DC-cable to the main logic board.
6) We’re done!
In this case i had to double check few things as the wiring was different than any of the previous /// power supplies i’ve had so i ended up swapping few cables around. But in the end, it worked perfectly.
Only thing that is annoying by design is the DC-output cable that goes from power supply to the main logic board. The opening between the power supply and the “wall” where the logic board is located, is quite small. The memory card connector hits the cable and it’s very tight fit almost damaging the cable itself. I would say that is design flaw by Apple originally.
RUBBER FEET REPLACEMENT:
The two front rubber legs were missing so i replaced them with replacement ones. The ones i got from ebay were slightly smaller (but good for the Apple II) so i placed small piece of another kind of rubber sticker under it (cutting it to correct size) and the height was the same.
INSTALLING THE NEW LIGHT BULB:
These lamps are available these days only online, atleast i couldn’t find any locally anywhere. Those lamps are around $1.00 each depending where you buy them. The shipping in the otherhand… that was pricy. But what can you do? One could, if know how, replace them with modern led-lights. I just wanted to have the original style replacement at this time so i bought 10 pack of original Sylvania 7328 6v 0.2A bi-pin lamps.
It’s very easy and straight forward job – first need to remove the keyboard cover by just removing 5 screws underneath the keyboard and lifting the top of the keyboard part away.
Removing the old lamp is easy, just pull it. It comes off easily.
Replacing the new one is slightly more difficult as you really can’t see anything. Just push gently the new bulb in as straight as possible. The legs might get bent easily so get them straightened if needed. Replace the keyboard cover after you’re done.
I notised the keyboard cover was bit in “suffered” state, meaning the holes where the screws go (plastic pilars with hole on them in middle) had broken off from the right. Those would need fixing somehow or replacement cover.
As i had opened the /// several times over the weeks, last time i had put it together i had ACCIDENTALLY installed the DC-cable to J20 connector for some odd reason… so it would not power up. Now that’s not good! So i installed the DC-cable to correct connector (it DOES read “POWER” on PCB..) and powered it up, it DID power on but it did not display any video on LCD and very distorted image on very right side of the CRT monitor as well. BUT it did boot software so far i could see. So it’s not totally busted! We have (new) hope..
REPAIRING. AGAIN. (get used to it, it’s Apple ///):
Thanks to technical assisstance at Facebook’s Apple /// group, i was suggested to replace the first chip on line, 74LS153 (0.58€/ea locally). So i got few and replaced one. Sadly that didn’t help but i was very kindly assisted further looking into other chips in that line:
U90: LS153 @ L8 dip16 74LS153
U119: S175 @ B12 dip16 74LS175
U141: LS00 @ H2 dip14 74LS00
U146: S86 @ B13 dip14 74LS86
U147: LS11 @ K8 dip14 74LS11
Swapping these however did not help. I had bought few more chips but didn’t test them at the time.
Something odd happened! Later, after a long period of time, i tested the machine again, with different monitor and … it worked. WTH? What just happened? I am not sure if actually swapping the chips helped or something else happened. The “new” Samsung LCD/TV does better NTSC even not perfectly correct colors however. But – i’m not complaining.
On thing i noticed (finally) however:
The European /// have (naturally) different crystal (50HZ) 14.25045/1970002. Making it NTSC/50HZ so that explains why no colors on most displays. It uses Video chip : 341-0060-A (instead of 341-0030-A in North America)
341-0060 – III – ROM 2kb*8 – Video scan decode ROM 50 Hz
341-0030 – III – ROM 2kb*8 – Video elements/attributes generator
TESTING THE SWEDISH/FINNISH-KEYBOARD LAYOUT (configuration file)
As this is Swedish keyboard model (same as in Finland) i thought to see how the localization works with SOS. I booted the SOS Utiltiies and with SCP i loaded up the language/keyboard configuration and saved it. It’s fun to see those ÅÄÖ on screen even i prefer US-layout in a long run. Happy to see Apple did put effort on localization this much. This leads me to thinking, there problably never were any Apple /// original manuals translated to Finnish?
Works in any SOS disk with SOS.DRIVER file on it and the driver added naturally.
Fully functional /// – is that even possible?
So after all the trouble, goofin’ around and repairs, the /// seems to be working fine. My herd of ///’s have grown since i started this article – so more repairs were ahead with two more of these. Luckily slightly easier. /// is great machine with lots of potential. It’s great shame no more homebrew hardware/software have been released to it over the years.
What still i haven’t figured out is that strange “humming” noise that most if not all, Apple ///’s make. It feels like it comes from the speaker… but why? Or is the the grounding in PSU causing this?
FinApple 2020 (c)
Apple /// Forever.