TRS-80 Model 4P Test and Teardown

[@fishx0ff]

The long videos with all the dirty details are great. Don't worry about the length. I really appreciate learning about the depths of the whole system which you only get from the false starts and dead ends, and all that extra time gives me a chance to actually absorb and remember some of it. Not to mention it's a much better reflection of reality--at least *my* reality when troubleshooting something!

[@Dragonborn_1992]

I completely agree with you.

[@ceebee23]

absolutely.....

[@SockyNoob]

Agreed

[@essas.coisas]

I feel the same way

[@sq1rlsqu4d]

Exactly this :) I'm not sure that folks with short attention spans are the target audience of Adrians' videos anyway ;)

[@CapnKetchup]

For these kinds of technical videos, lonnnnnggggggg format is just fine with me!!! Do what you need to do in order to show us how you fix things. Thanks for all you do!!!

[@jwhite5008]

We totally can skip ahead if we want to - not that I ever was bored on Adrian's video. Even if you make mistakes - everyone does - we will gladly learn from those and be thankful. You can cut probing all 16 lanes if they look the same, and repeated disassembly-reassembly too, but other than that - leave everything in.

[@LKonstantina915]

its weird how I never skip, I usually grab a snack and watch. Its weirdly entertaining.

[@TurboCharged_RubberDuck]

The more Adrian Black we get the better! Long videos are definitely NOT a problem!

[@acidhelm]

I like long videos!

[@geordish]

I don’t like long videos. I love them!

[@petefish9401]

I don't love them, I adore them ;-)

[@kittyztigerz]

i agree longer is better i enjoyed it

[@TheGunnarRoxen]

Long videos are better. I love the details!

[@LynxCarpathica]

Indeed, the more technical, and in-depth a part is, the longer the better. More info, more to learn, and more to explore. love the lenghty videos, where you try your best to find the fault.

[@8bitwiz_]

One warning for when you put the whole thing back together: the 80-column horizontal sync depends on a little varcap in the middle of the motherboard, and the CRT will not sync to 80 columns if it is incorrect. I'm pretty sure it drifts over the years too, making the chance that it needs adjustment approach 100%.. This might also be why your HDMI converter is having problems. The difference is that a CRT will show something if the sync is wrong, but digital converters might blank the video.

[@jwhite5008]

Yes! (Had no idea about the variable capacitor, or model 4, but this makes a lot of sense in this situation) Leaving the comment here so that youtube may give it more priority.

[@stevesstuff1450]

@@jwhite5008 :Ditto...!! 🙂

[@TechnicolorMammoth]

I don’t mind the length. I understand that these tear downs, repairs, etc can never be set in stone time wise. It’s illogical to think otherwise. Sometimes a video does have to wait a few days till I get a chance to watch the whole thing, or it’s broken up and watched on breaks or the like. I love these videos. Especially the repair ones, and the longer they are the more I know it’s gonna be a good one! Keep up the amazing work, Adrian. I admire your work ethic and passion. I try to personally emulate that in my personal and work life.

[@Unfinished80]

I'm going through a really hard time in my life right now but your videos are always bright spots on my week. I really look forward to them. Thank you Adrian!

[@sirtanon1]

I feel for you. Keep your head up. Focus on the good things and you'll get through it.

[@Unfinished80]

@@sirtanon1 Thanks!

[@Unfinished80]

@@martinr1834 Thanks!

[@InfiniteLoop]

Adrian, we don't mind the longer videos, we just like the tech and the repair stuff. you're doing a great job.

[@HERRH1]

Really like the technical details and the way you try to make sense of it all looking into those old manuals/designs. 45~60 minute videos are fine as we still want to know all details 🙂. Keep up the good work!

[@tiemenfiat1321]

Your production rate of video's is astonishing for a non fulltime KZbinr. 40 minutes is great and the detailed repairs too. Ga zo door! (Keep on going like this)

[@Nimmbin]

Length of your videos is just fine. I enjoy the everything you create so keep em coming my friend 😁

[@roadsiderebels3039]

You sir, are an entertainer. The longer the better!

[@julieileneowen]

I like the long videos. People can always skip ahead if it's something they're not interested in specifically. But for example, I have a model 4p, which basically works, and I've been wanting to open it up, but knew it was going to be a real hassle, seeing that teardown on what to do, and not do was very helpful to me.

[@parrottm76262]

Another vote for the long(er) vids. Love the deep dives. Those are the most likely to teach us something we never knew. You can always come back later if needed (modern problems).

[@pastedtomato]

"This could be a somewhat quick video" Famous last words. Jokes aside, I love long videos, I really enjoy the troubleshooting and explanations

[@erlkiing]

i do love your longer videos, its something i enjoy listening and watching while i work on my paintings, the more the better!

[@Mil_UwU]

Just came to say I'm a big fan of the long videos!! Cheers!

[@SC-CAJUN]

The length is fine! Longer the better for me 🙂

[@HamJamming]

I really like your TRS-80 videos because back when I was a young guy I owned both a Model 1 and a Model 4 and used them both heavily for over 10 years, under both TRSDOS and CP/M, before I had to switch over to Windoze.

[@Mrshoujo]

Your videos are as long as they need to be. No shorter or longer. If it takes 45 minutes, it was supposed to be. If it's over in 21, cool anyway.

[@k4tfjprojects296]

❤️ LOVE ❤️ long videos... I hunt for them!

[@Astragali]

Adrian, the long-form videos are absolutely fine - I find all your videos very absorbing, so it's always a pleasure to get the longer-duration vids.

[@PatrickFinnegan]

These longer videos are great!

[@SimonZerafa]

Am I the only one that prefers longer videos? The longer the better in fact 😁

[@SC-CAJUN]

Hi Adrian! You need to insert *both* diskettes I included, with the ROM disk in the left drive, and it should boot just fine. The ROM will load first, then TRSDOS will load from the right drive. Your CPM disk might load that way as well, but it has to read the ROM disk first in the left drive afaik. That’s how it was working for me. Good luck!

[@adriansdigitalbasement]

Actually both disks you included do boot the system -- but only once I had the machine on the bench as it just refused to boot at all when assembled. There are other issues as well which I will show in part 2 :-)

[@SC-CAJUN]

Thanks so much for working on it. I had good fun with it for 2 days :-) I hope you enjoy it as well. I definitely saw some issues with CRT blinking out to a single dot in the middle but was hoping some cleaning might help with that. I hope you can get it running stable! It is a really special machine and the size is great. I’m sure this is more fun to move around than the Model II or even Model 3/4, and this one is more capable than the Model I, so kind of the perfect TRS-80 M-X series.

[@danfm1]

This machine looks awesome, this is totally something I'd imagine a hero of early 80s movie would use in like an abandoned lab

[@user-yr1uq1qe6y]

I went to the barber today and the young lady asked me if I was going to be going out for a date or something. I didn’t have the heart to tell her that nope, I was going home to watch several men fix some old computers. We certainly are living life to the beat of a different drum and I love it!

[@MrEd-qg8td]

The 4P did not have BASIC in ROM. That's why the Break key does not let it boot up in BASIC. In order to use Model III BASIC you needed a hidden file called MODELA/III which was the BASIC code in a single file. A Model III disk should have this on it already. And Having a 4P you don't need disks in the drives for it to boot up.

[@Jody_VE5SAR]

Long videos are the best! Now... for a dumb question... since this machine is booting ROMs from disk... is there any chance you can create a disk with your new TRS-80 diagnostic ROM image on it and run it on the 4P?

[@monkeywithocd]

Repair videos I feel should be as long as they need to be. I think the videos work best when you stop the video when you have to take a proper break.

[@logicfry]

I love the longer videos.

[@andydragon69]

Like others here, I love the longer format. I have learned so many things that as a mostly software guy who dabbled in hardware I did not know. I also love that you work on so many different computers, it's eye-opening seeing all the different architectures.

[@gazza8234]

I own a couple of 4Pees. Modified one with internal 360k, 720k and external floppies, XLR8er 512K ram, Hirez graphics and battery backed RTC. Also modified the boot rom so it sets the XLR8er speed at boot, loads the MODELA/III Rom image from the hard drive and can also boot from an IDE hard drive. Luv my 4Pee, best comp Tandy made. BTW check the soldering on the Power Supply output connector. It WILL need repairing also replace the yellow time bombs on the P/S. Good luck.

[@brentboswell1294]

By the way, Adrian, the guys in the RadioShack Computer Store called the TRS-80 DOS "trisdos" back in the day 😉

[@belzebub16]

41:45 I was really supprised to see German messages on the screen, apart from English and French. Was this machine ever sold in Germany or the EU? Because I'm from Germany, but I've never in my life seen a TRS-80.

[@adriansdigitalbasement]

It's a really good point!! I have no idea, I really don't think it ever made it outside the US, Canada, Australia and the UK!

[@timothyp8947]

Have no problem with the lengths of videos - I guess the advantage you have over a normal tv programme is you’re not making a programme to be a particular length… you can make it the 'right' length for whatever it is you’re showing, be that shorter or longer. Enjoyed this episode on another more unusual beast. I like all retro, so don’t mind about brands… this isn’t the '80s when we all favoured our particular machines 😊

[@Homebrew_CPU]

For what it's worth, the little HP pin comes from the late 80's or early 90's and represents HP's PA-RISC line of computers. The program was internally code-named "Spectrum", thus the rainbow on the pin. I don't remember for sure, but marketing may have also used the term "Spectrum" in external advertising as well. I've still got my Spectrum pin around somewhere....

[@charlesjmouse]

Who can take a sunrise? (Who can take a sunrise?) Sprinkle it with dew (Sprinkle it with dew) Cover it with solder and a miracle or two The Tandy Man (the tandy man) The Tandy Man can (the tandy man can) The Tandy Man can 'cause he mixes it with love And makes computers real good (Makes the computers real good)

[@falksweden]

The longer videos, the better. The impatient ones can always fast forward but we who enjoy detailed and long videos can't add content that's been edited out :)

[@Dreamshadow1977]

I have no issue with long episodes 40 minutes to 60 minutes. It's a decent length, and I look forward to new troubleshooting videos.

[@basgialopsos2600]

Hi Adrian Awesome work chap, felt for you trying to get that Model3 rom soft loaded. You are right M4 discs should boot straight to 80 column with no Rom softload. However using my M4 mainboard RGB2HDMI 80 column mode doesn't display properly at all although M3 mode is fine. I've asked the boys on stardom if anyone got 80 column mode working yet .

[@OtherWorldExplorers]

Both Keep it around 45 minutes for most of us. And really long with a few cuts as possible as a tutorial video for those who could benefit from it... Maybe another channel.

[@Gloworm17]

I like a mixture of both. Long videos give me the length and depth of a TV show proper. The short (5-10) videos giving me something to pass the time while doing something else. I can watch the short ones in a restaurant vs having to plan to watch longer ones.

[@DeepThought007]

Adrian I just rewatched the sequence where you tried to boot off of the floppy disks. I noticed every time you tried to boot you booted from the left drive. At least before the monitor started to work. I wonder, do you think you should be booting off the right drive? Maybe the external drive that you connected later was the equivalent of the right drive before you took the machine apart? Just a thought.

[@JohnJones-oy3md]

5:36 - The Model 4P all buttoned up always reminded me of a sewing machine case.

[@projectartichoke]

I'd always rather a video was a bit too long than too short. It's always possible to click ahead a bit if things seem a little slow. But, of course, your content is always riveting.

[@K-o-R]

Aaaaahhhhh scratching the LCD screen 😨 I had to stop and think a moment as to what a "Gatorade" and a "non-Gatorade" version of a computer was.

[@jurelwow]

I vote on long format. hourish is always good i save them for after i get off work. have for a long time!! keep up the good work from van buren arkansas!!!

[@paulstaf]

I never can understand why people would complain about a long video... this isn't network television, you can fast forward through parts you don't care about, or watch it at 2X speed.

[@tarzankom]

I like the longer running videos. 40-50 minutes (or even longer) seem to be a good amount of content.

[@DeepThought007]

Take the time you need to do the videos! That's what makes them fun to watch. You're thoroughness.

[@SockyNoob]

Bubble wrap is so ridiculously cheap in giant rolls, I have no idea why sellers don't actually bother wrapping fragile items in them. It's not hard to do.

[@jrnovosel]

While it's apart I'd retrobrite it. At least the case and front bezel. You can do the keyboard later.

[@Flashy7]

there are great service manuals for these - but let's just remove screws until everything falls apart :)

[@mindbender50]

Its the content that matters...if i see a long video and throughout the video I see trials and tribulations that can help me in my troubleshooting I will love it... time is relative.. even failures are helpful! That being said I have yet to follow you down some deep rabbit holes that I did not view them through to the end I love your channel..:)

[@JamesBondJr]

dip the copper wire in gold and the coin ok im tired of it there the best sound =] that gos for video aswell also you can use fools gold yup yup 💋

[@BrickTamlandOfficial]

as for long videos, i like them a lot more than short videos. but i also get it that shorts on youtube are going to be a big deal and they are going to monetize shorts as well so that could lead to more subs and views and money for you. so I wouldn't blame you if you went and did the shorts at least while they were popular haha.

[@eddiepetrick6222]

The two different successful disk bootups near the end of the video had different opening screens. The first was prompting for inputting the date, and the second had "TRSDOS Ready" in the same place. Don't know if that matters to anyone.

[@8bitwiz_]

The clock data was probably already set (to something) in whatever location it belongs, and checked during reboots. It just doesn't have a battery to keep it set all day.

[@RudysRetroIntel]

Long videos are great but the long time to open that computer, not so much. Hope you remember how it all goes back :) Great video, as always!

[@JamesBondJr]

all in one desk combo cheese wedge desk for coners one cord think about it .....💋

[@dodgydarryl]

I love the honesty of all the false starts and the struggles you have to find these faults. I think if you edit them down too much we would lose the sense of challenge in these repairs.

[@xenonkay]

That packaging ticks all the right boxes and it's way more than just the bubble wrap. Not only does the quantity of bubble wrap provide good padding, but the foam and other filler eliminates crushable voids and provides crucial separation of items from the outer box walls and each other. And equally important, the box itself is in good condition and sturdy. Way too many people make the mistake of using under-specced or worn-out boxes that just tear out, collapse in shipping like a wad of paper, or they cut down or tape together boxes to fit and end up with a frankenbox that has zero edge strength. That leads to the weight of other stuff it's piled under or up against during transport to possibly crush the goods even if it's mummified in bubble wrap.

[@pinchaser]

Thanks for the "Gate Array" text overlay. I certainly heard Gatorade.

[@KralleLion1980]

you got the right mix of details and not overboarding dead air. so if a video is longer, it needs to be. all fine

[@dugmeister65]

Hi Adrian, you mention that Radio Shack has amazing technical manuals, which they do, so why don’t you read them to see disassembly instructions? It would solve a lot of your woes initially…. It would make the video a lot smaller and make it more useful. If folks are trying to learn how to from this video, it isn’t a great experience.

[@ultrametric9317]

WE all love these videos!!! It doesn't matter how long they are. Most of us have spent hour upon hour trying to diagnose computer problems, hardware and software, and we know how time can get away from you. It's fine! You skip over the obvious parts and we get that too.

[@elHosed]

I personally like the longer videos. I usually play them when I'm going to sleep and come back to the parts I slept through later. Gets you at least 5 views from me from each vid as well ;)

[@8BitRetroJournal]

Adrian, you are killing it for #SepTandy2022. Love all of your TRS80 content! Seth is starting to rival Stuart from NH in what he sends in to you.

[@thatredkite8310]

I really love long videos

[@SudaNIm103]

I like the longer videos. I’m usually feeling up to speed with the topics you cover; Often the most enjoyable aspects of your videos are brief off-hand comments: you reasoning aloud about a particular symptom, or rhetorically offering a brief bit of insight into why a troubleshooting approach I’d have waited to pursue is in the forefront of your mind. It’s often those moments that leaving me feeling like I really learned something scarce and valuable. As much as I enjoy the rare cases where I’m maybe one step ahead of you and I’m yelling at the screen; it’s the times I’m left a bit shellshocked by your experience and insightfulness that are my favorite. ❤

[@TheRattlebunny]

I completely agree. Longer videos are great. I’m dealing with a diabetes related infection in my leg which is keeping me from my own channel, but worse it’s keeping me out of my own lab. So, I live vicariously through your videos and those of your fellow recent panel members. So, thanks and keep doing such a great job. 👍👍👍

[@JamesBondJr]

Toshiba C-500 color portable TV AKA hobo computer just add a power bank /raspberry pi =] your welcome

[@JamesBondJr]

easy 100$

[@baremetalHW]

Long format... people can fast forward...

[@Derpy1969]

This R2 unit has a bad motivator. Look!

[@Vermilicious]

I think 30-60 minutes is a good range for a video. But of course, more interesting stuff can be longer too, but it's probably a good idea to break them up a bit. But that's already the case, so I have no complaints! That's an interesting looking computer you've gotten right there, "portable" and all.

[@Fhensleytx]

Wow, 130+ comments just a few hours after posting this 48 minute video! Adrian, your fan club is alive, well, tuned- in, and loving the in-depth stuff. Great job!!! Also, would you ever be interested in doing a video for a unique TRS-80 clone from back in the day called an LNW-80? If so, let me know and perhaps I can assist with getting you one. Take care!

[@isoguy.]

Be more than happy with 2 or 3 hour vids.

[@JamesBondJr]

why dont you recycle tube monitors and put raspberry pi's in them and sell it for the right price =]😈💋

[@JamesBondJr]

like old droid phone to computer =]

[@JAMIEvx]

I enjoy your longer videos as much as the shorter ones!

[@BobPlank_KK4DIV]

I really enjoy the long videos. Keep them coming. Since finding your channel, I have really learned lots about repairing old electronics and I enjoy seeing all the details. Someone gave me an old TNC used in ham radio packet communications with some leaky battery damage that I am going to attempt repair after being inspired by your videos. I opened it up, saw a Z80 processor and some other components that looked familiar and thought to myself, I may be able to do this. Again, thanks for the videos and I appreciate the long ones.

[@wintermute740]

I like your videos. Long or short, I don't care which, because they're always both entertaining and educational. I could have never restored a 5150 to add to my collection without your videos.

[@volodymyrzakolodyazhny]

Short or long - it depends. Interesting repair is like a detective film. Yours are typically fine. If you add small ones - ok.

[@Codeaholic1]

I'm all about the long ones. ;‐)

[@drgiller]

The shirt is awesome!

Hi Adrian. The MC-10 was NOT compatible with other CoCo's, unfortunaltey. Because of that, it was a flop. I bought one back then in liquidation for pennies on the dollar. They also sold a 16K memory expansion pack. Thanks!

[@AnotherMaker]

Thanks for the awesome content as always. Thanks for the tip on using the RGB2HDMI. I'm definitely going to make up a cable and us that moving forward. Every model 4 I have, had PSU issues, so I finally just made an ATX test harness and it's so helpful on these machines.

[@ChildrenOfTheRosary]

If all else fails, read the directions!

[@s.lancaster2830]

I like long in-depth videos. Once or twice a week I have the need for some long form computer-related content. And your channel is perfect for that

[@ObiWanBillKenobi]

30:36 I heard “Gatorade version.” 😆

[@LordChariot]

I'd love to see you retrobrite this one.

[@Kikay0n]

I think the length of your videos is always perfect

[@SmilyTheMare]

length isn’t important what is important is the quality making sure u include anything that can help others is what matters

[@tony359]

Very cool video! those machines are so primitive and so fascinating at the same time! :) Looking forward to part two.

[@RyeOnHam]

Love the long format. Longer would be fine. I watch you at 1.5 speed and pause it to watch other videos if I want to.

[@MrJavix09]

your long videos are great. I just love the great work you do explaining everything. you've got me thinking to finally go ahead and take a soldering class so that I can try to fix my Amiga 4000 myself since there are no known fix computer shops around, only LOTS of potatos. 😅

[@automateTec]

Right arrow is 5 seconds. Left arrow too.

[@ovalwingnut]

Like McDonald's.. "I'm loving it"... Thank you for the ride along.

[@droganPaul]

Long videos. Let us see your whole journey and save yourself too much editing. No need to change... it's freaking working...

[@tommuller817]

longer is much better...I know youTube like 15 minutes best ...but please don't follow youTube