Macintosh Plus black screen repair 

My dad bought me a Mac plus in 1987 to bring to college - I used it until about 1990 and then put it in a box until last year. I recapped it and it works as good as new, even the apple HD20 works and I now have all of my college papers! It was a blast to read them. I also have some stuff I downloaded from bbs’s. Man those were the days, when only nerds and techies were online…

FYI, the Mac Plus does not supply termination power on the SCSI bus. It can be modded in with a diode (that might make for a good follow up video), but most haven't had this mod done. Any device like a BlueSCSI that draws power from termination power won't work unless you supply external power (as you've shown). Even then, sometimes the external power for the device might not be adequate for proper termination load for the bus depending on the device, its termination resistors, and the cable length. I'm not sure how well the SCSI2SD supplies term power. The Zip drive can also be sensitive to termination power level when it's the only device on the bus as its notorious for weak termination. I've used DB25 BlueSCSIs with external power when attached to the DB25 port, but as soon as any kind of cable length is introduced it starts having issues. I bet if you plugged in a real external disk enclosure (with an actual SCSI HD inside) and then plugged the SCSI2SD in as a terminated device everything would work fine. That's because most hard drives of that era will supply termination power. Or an external CD-ROM/SyQuest/Jaz/whatever.

Week 3 of watching your content with absolutely no need to repair anything old tech. Nor having Any background in tech. But enjoying non the less

Sympathise over the annual eye check; it’s amazing how blurry it makes the world and it can even make it near impossible to see in very bright conditions. There’s something very appealing about those compact Macs. Never really got to use one, although remember seeing one during my final few months at college back in 1987. Did at that time get to use a micro vax workstation with a bitmap screen and windowed VMS, along with a Sun 3 workstation.

Always worth reminding people to be very careful not to bump the neck of the tube as that can release (let in?) the magic smoke. I did that once.

Sony use those black plastic push-pins too and I found that an effective way to get them out without pushing from the other side is to use a pair of needle nose pliers and grip the flat part from the edge and pull straight outward.

This really brings back memories. I had found a Mac 512k at a thrift store, ages ago. It had HV issues and I purchased a used board and had it up and running. I have quite the collection of thrift store finds still, and this video makes me want to get the old ones out again and play. Adrian, thanks for putting this up, I really enjoyed it!

These things really are tanks. Mine survived a flood (submerged for hours), and only the analog board needed to be replaced. The floppy drive spindle motor was loud and scratchy and I needed to relube the eject mech, but it still worked perfectly. Cleaned rust from the metal bracket that's soldered to the rear of the logic board, checked the caps, and all is perfect. No parts of the tube rusted whatsoever and somehow got absolutely no water in it. It's very, very hard to completely kill a Mac Plus.

Wow!! A Zip Drive ... that brought back a whole bunch of memories. Those were the greatest thing since sliced bread.

Well I just got a Macintosh Plus and it had the exact same issue and the things you did fixed it! Thank you!!

Great repair and especially enjoyed that it portrayed the real experience of retro computers, back up plans to backup plans to get around those snags that stop a fix. I went through so many options to get nextstep working on a sun box. I pays to have a lot of alternative tech around as they all have quirks.

The original Mac case design may be one of the friendliest designs ever.

Thank you very much, exactly the same prob! Just the boing and a black screen. Reflowing the joints of the connectors did it! 😘

I guessed it was the solder joints on the video connector before I even started watching the video - that was also the last repair I did to a Mac Plus. It was also the last cheap retro computer I bought from anywhere before prices went silly - I managed to buy it off eBay for £10, and it was a local pickup. It's been in my loft for years because the floppy drive scratches and ruins any disk that's inserted. One of my other Mac Pluses has a wobbly picture and a blown SCSI chip, so I was just going to swap the floppy drives over, but I never got round to it.

Even though I'm not a Mac person it's nice to see older Macs getting some TLC 😄

Sometimes it's nice to have a repair that's so easy and quick to fix, cos having to reverse-engineer things to figure out how it works in order to repair it can be a headache, so a simple revival feels quite satisfying... :)

I must commend your excellent walkthrough of this Macintosh Plus repair. Your methodical approach, coupled with your clear, concise explanations, really simplifies what could otherwise be a complex process. It's refreshing to see such dedication to preserving and maintaining vintage technology. I'll certainly be referencing this video in future restoration projects. Outstanding work!

adrian i have to give you credit for being a die hard retro computer enthusiast! i just found your channel and it is great because i love retro computer and game consoles...you have a ton of good videos! thanks adrian!!

There's something about Adrian that I like a lot, which is always adding knowledge about everything that is happening in the video, not only about the Mac; e.g. the tip about the Zip drive's power supply and to not mess with the voltage regulator on the board. That shows a lot of care and attention. Kudos!

The screen is 72DPI, so you want to adjust the screen so that 1” measures 1”. You can use a ruler right on the screen.

The Macintosh Plus was introduced in early 1986 and discontinued in late 1990. IIRC, it was the longest running model of Macintosh; all other models ran for about 1 to 3 years tops.

A few months ago I pulled out a 512k Mac I inhereted. Two issues with it: the internal floppy drive didn't work, and the video signal was intermittent (it would come on if I gave the machine a good whack). I did pull it apart, but unfortunately the piece of card on mine was held in with double-sided tape so I didn't want to pull it off unless I was reasonably confident of a fix. So I saw this, thought "yup that is the fix" and put it on my to-do list. Just took the machine down to my digital basement and reflowed those connector joints, she now works. They were very nasty, and obviously cracked. Thanks!

I have two of these machines, one of them I keep on display in my office with 4 MB of RAM. It has a SCSI2SD in an external hard drive enclosure. The only way I got that to work was because of some tips that you gave me a few years ago I think you again and I’m glad you have one as well. You are right. It is a very reliable machine!

My first Mac. One of Apple’s best machines. I bought mine brand new in 1989.

Thank you. Excellent as usual 😊

Macintosh Plus! The computer I started on, still own it. It still works. Had to reflow some solder joints. Had to repair a crack in the keyboard. Now it's supported by 3 Raspberry Pis - (1) a Pi Zero running a RGBtoHDMI (I have you to thank for being inspired to do it from your Classic RGBtoHDMI video) (2) a Pi Pico running a BlueSCSI v2 and (3) a Pi3b running a USB4VC if I want to use modern peripherals (usb mouse and keyboard, wireless bluetooth playstation gamepads) using the spanking new protocol card for early macs+lisa+adb macs!

My high school’s business studies department had a lab of mac pluses all networked to a LaserWriter II, later on a 2nd mac lab was installed with Mac classics

Adrian's so good at fixing old computers, he doesn't even need to see to get them fixed lol

Nice repair. My aunt had one of these for a long time. Every 3-5 years it would quit and I'd tweak the 5V voltage reg a bit to get it back to spec and it was good

I just took my dad (also a diabetic) to have the exact same thing done on Friday morning. Everything was good for him, I very much hope everything went well for you, too!

That Lazy Susan is a good addition to the bench

Love the Plus. The 1MB memory was awesome for it's day!

Hi Adrian, I'd like to thank you sooo much for the tip about using an audio spectrum analyzer to detect the the HV is present on the tube. I have an HP-150 which had a blank display, and I thought that it was due to a failed flyback transformer. But with the help of a spectrum analyzer I determined that the display was in fact driven, so the cause was elsewhere. Eventually I found that the problem was with the intensity knob(!). Now my HP-150 is working again. Wooow. Thanks again Vassilis

Great video Adrian! I should really get myself a compact Mac at some point.

I love those Macintosh videos. Always hope the next one will show how to fix the issue I have on mine 🤣 great video. Thanks

I was hoping you would have tried a Blue SCSI as well. Great fix, once I got an abandoned 26" color console TV and found a burnt wire on the yoke plug in 2 minutes by doing a visual inspection, free TV! It can be simple or it can be hard. Keep up the good work and videos.

I got 3 of these last summer from an newspaper company that did some spring cleaning, so far I just need to test an OS on the big one, debug some glitchy video and recap another, and figure out what's even wrong with the last one since it might be absolutely dead. There was a mac classic as well, but the inside literally turned to dust when I opened it and the board is almost completely corroded. Did some cleaning but haven't looked at it or the others in over a year, will be working on those and watching your stuff for sure.

You absolute genius! I have a proprietary monitor from a Brother word processor that I repaired. I absolutely cannot work out the sync rates. I never thought of using a spectrum analyser!

Enjoyed Adrian's LongPlay Crystal Quest video. Nice one. Need to change the title of the video to LongPlay Crystal Quest

Love the Zip boot disk I did that all the time back in the day

"Is it booting? It is booting indeed." For a video that came out shortly after Easter, that really tickled me.

Ooooh I had a couple of these back in the day. Tandy IBM clones too. I really like your intro music, and the 8 bit feeling video filter. Very catchy and cool.

Great fix and now I want to play Crystal Quest!

There is that engineering spirit. I cant see well so bonus points if I can fix it!

I enjoy seeing another classic mac restored to working condition for many more years of fun!

I see... on a video recorded on 4/20, it's the "eye exam" that dilated Adrian's pupils! :D

You reminded me that I still have to fix my Mac Plus - the flyback on it died, and the Dalbani sourced one i got never worked - luckily i found out that the one from the SE work, as do ones from the Classic, too.

I used to "operate" on Pluses, SEs, and lower II-series in my high school's two Mac Labs. My initial hope after the successful "bong" was waiting for the tube to warm up and to see the flashing disk with question mark, crossing my fingers that we wouldn't see a Sad Mac. When the CRT didn't come up, but you felt static, my immediate diagnosis was "cold solder joints on sweep board at the mobo connector" followed by "cold solder joint on sweep board at the flyback transformer." I've seen those two failures so often... The high school had a breakout lead that plugged into the floppy port to check system voltages. I actually did, on the rare occasion, tweak the "Voltage" pot when needed, but if I couldn't get both voltages into spec through that adjustment, I discharged the caps & CRT, pulled the board, and packaged it for transport. We had a company we ordered refurbished boards from that had an exchange program, it cost the school $185 per refurbished board. Much cheaper than ordering from Apple. When I graduated in '96, there were far more refurbished boards than original boards in use. We ended up modding fans in all of the Pluses to pull heat out the top, which helped keep them from self-destruction. 11:49 - Congratulations! The common failure points are always worth checking first. (As you said, the compact Macs are fairly bulletproof - aside from the SIM slots.) System 6.0.8 is the latest System that will run well on that architecture. The poor things just can't handle 7 very well. System 7.5 boots in roughly seven and a half minutes, which makes it rather appropriate (4 MB RAM, plus an aftermarket accelerator card boosting me to 16 MHz). Of course, with System 6.x.x, you could have a functional OS, a Word Processor (with Spell Check), a handful of extra fonts, and room to save a few documents all on the space of an 800K floppy disk, which was pretty convenient. A hard drive failure didn't mean you were dead in the water.

Nice, I used to be a Mac tech back in the 90's... I have seen way too many of these... and I am glad you liked and use the Metallic Sharpie! Also, missed you at CoCoFest! But look forward to seeing you at VCFmw in September!

In the '80s I had an Apple dealership on the UK south coast. Had a phone call from the USS Iowa in the Bay of Biscay; their Mac had stopped working and would need it to pay the crew, I understood. They didn't have the long tool to open the case, so Iowa came alongside at Portsmouth for me to fix the Mac. Most of the internal connectors had separated, so I simply reseated them all and it worked. The likely reason for the partial disassembly at sea was that they had been practising broadsides - well, the Mac wasn't designed to withstand that kind of punishment! Had a conducted tour of the ship too, most impressive.

I believe that Zip drives have weak termination voltage. That drive mechanism, while revolutionary in the mid-Nineties, ate up damn near all of the 2000 mA the OEM power supply could output. They also started to droop in voltage with age. Instead of 5.0 ± 0.5 V DC, they'd drift to like ± 0.8 (usually always on the low end). So, if you're P/S has dropped to 4.2 volts, you're down to 1600 mA-barely enough to power the drive mechanism. Termination voltage (talkback) is 0.4 ± 0.1 V DC. So if the output voltage has drifted within that overlap, talkback will be intermittent, at best, because of the drop in milliampere (mA). So yes, a new (or even just more modern rectifier) power supply, will keep that voltage right at 5 volts, thus the full 2000 mA needed. Check the adaptor specs: minimum output should be no less than 2000 mA (2.0 A) and no _more_ than 3500 mA (3.5 A).Otherwise, I've found the sweet spot to be 3000 mA (3.0 A). More than adequate power to supply the drive, the logic, and the termination signal, without drawing more than 0.7 A from mains.

Eyes dilated and you're making content? That's dedication. I sit in a darkened room for a few hours after that procedure (just regular sight tests).

Love seeing Casady & Greene (and Patrick Buckland) show up in the 21st Century.

Love my Mac Plus.

What we did in the past, 80’s. we broke out som ribs in the top and put a fan in there, just a size that fits, running on relative low voltage, so low noise, to increase the airflow and get better cooling of the analog board, to extend the life of the board.

Great video Adrian. I personally found that SCSI2SD does not work with older compact Mac’s than the SE (inclusive). However BlueSCSI units work perfectly.

Love the max plus. Loved the extra ram and the scsi interface. A vaguely remember using one of these with a scsi Ethernet adapter to let it access an Ethernet network and an Apple talk network.

I love your vids sir! :D I have 3 "Plus" to fix in my queue :D

“Not going to have no video signal though” - the one time that grammar is correct 😆

Those Sharpies are really great for black power bricks. They don't seem to fade.

Adrian soldiers on even when he's blind :-)

I have one of these, fell off my table, still works.. only problem i have is I can't find any floppies to get it up an fully working

HA -- I think we were chatting when he gave you that Sharpie at VCF East!

Happy eye checkup! 😁Have to go for my checkup soon. Fellow diabetic

They were making Mac Pluses in 1988, I received a new one as a freshman in college. I believe they were still going for a year or two after that.

i still have my Mac 128k (haven't turned it on in probably 30 years). was forever fixing bad solder joints on the analog board to keep it running. it also has a Mac Plus ROM and 4 megs on a daughter board. my IIsi had it's battery leak to the point that it corroded 1/3 of the board and lifted the traces on the board, so it's completely shot. :(

I have an SE I need to dig out of storage and re-restore, it was damaged in storage a few years back. Never got the opportunity to use a Plus, but I once knew someone who had one as a conversation piece.

What's the firmware version of that SCSI2SD? I seem to think that some early versions didn't work with the Mac Plus? I have to admit, early in the vid, I was trying to tap the side of my laptop to "tap" the Mac Plus a few times. I've seen some vids where they did that to see a solder joint problem... That probably isn't a great idea to do to a running Mac tho... ;-)

Excellent work and video! Looks like you are able to fix a Macintosh with your eyes closed. Lol! Thanks for sharing

ZIPDisks were/are the unappreciated mass storage from that era. They were super!

The first computer I used (I was 5 years old at the time) was the good old Apple ][. The first computer with a mouse and a full GUI I used was a Macintosh Plus. To this day, I very well remember the sounds of the floppy drive on those Macs. I’ll take the floppy drive noises the macs made over the PC ones any day.

Greetings from Venezuela! Love your videos! Care to tell us what video equipment you use to make your videos?

Spectroid sounds like the kind of app that I've been seriously missing out on.

Adrian, enjoyed the videos, I have a Mac Plus with a sad mac face and a 01C82A code displaying, any advice ? Thank you !

6.50$ my god :) Those stickers are collectors :) Good job with the Mac, I have an SE to repair, I guess it's the same ?

Do you have a video where you recommend tools and products for soldering? Irons, flux, braid, etc..?

Here the uk (hull), i most of sold hundreds of them , great machine

Technically, fourth in the line - there was also the 512ke; which was just like the 512k but had the upgraded ROMs so it was compatible with the 800k floppy drive.

The 1989 date codes on ICs are no big surprise. The Plus was on the market for a long time - until 1990

Adrian, I would not be surprised if you can repair this Mac blindfolded! 😉

Ah, you might know. Is there ay adaptors for those older D-34V drives to modern 34-pin drives? I assume they're 26-pin... I have a system with D30Vs in it, but am curious about plugging in a more modern drive with 2 heads...

Cool trick with the audio spectrum. The 22 kHz is audible to me, but then my ears ring for quite a while afterwards. Is there any way to make it quieter?

My floppy emu allows me to select the mode when it starts up. Perhaps it's a newer sw/hw revision?

19:25 The Mac Plus was one of the longest-lived Mac models, being sold from January 1986 until October 1990! So this motherboard would still have been well within the regular production timeframe.

Love the old "Hershey bar" 68xxx CPUs 😊

Damn, after your "quick" game I now want to play that old original Crystal Quest, but I don't have any old Mac to do that.

I have an se and I've been trying to find an acceleration card without luck. Any ideas on where I can search other than ebay?

The Sad Mac code at 22:58 is 0F0002, in case anyone's curious and doesn't feel like going back!

Whats the rotating platform you used with the mac?

Studio lights and dilated eyes is dedication - ouch!

I do believe that there is a firmware setting that needs to be changed to get the sd2scsi working on the Mac plus. I have one that works, and I do remember having to edit the firmware settings on the sd2scsi device.

I have both types of the floppy emu firmwares on the SD, so I can switch between Mac and Apple II mode without constantly downloading firmwares.

I had an SE/30 with the 40Mb disk. Near indestructible one.

dilation..... code word for POT SMOKING! :) j/k ADB, keep up the good work

Aren't later monitors usually 30 kHz or higher? That probably won't get picked up by a phone since it's outside the audible range.

Oh lord, I hate those drops ... first time I had them, it took 4 weeks to wear off .... even street lights hurt at that time!

My mother bought a Mac Plus, it was around $4000 which was very expensive back then.

Did you configure the RAM 1 Mb vs 4 Mb with the RAM jumpers since you plugged in 1Mb instead of 4 Mb

I have one from 1990 or so, one of these days I’ll pop it open and start swapping caps.

I dimly remember the Mac plus was very picky about SCSI termination.