If these Jan Beta videos are anything to go by, the Jan Final Release videos are going to be out of this world!

@JanBeta

Жыл бұрын

Haha, thanks. I‘m not sure if I’ll ever manage to reach release candidate status but I’m working on it! :D

@jumhig

Жыл бұрын

Definately an improvement on Jan Alpha anyway.

Of all the retro systems I've had the pleasure to deal with and use, whenever I see an Amiga revived or saved, it warms my heart a little. Vielen dank Jan. Es freut mich.

Kudos on keeping the board original, Jan. Such an older example of the A500 should be preserved in its original form. I was never a fan of modifying boards, cases or anything else. I'd gladly plug in a modern accelerator or other peripheral, but I can always go back to the original when I want to!

@JanBeta

Жыл бұрын

Yes, I kind of feel the same. Putting new capacitors in would maybe be a good idea if the Amiga is going to be used in the future but I somewhat want to keep the changes minimal on the other hand, too. Not an easy decision!

I'll come back and watch this carefully as I'm trying to get my 2x 500s back up and running. Look forward to sitting down and watching it properly.

@JanBeta

Жыл бұрын

If you need more in-depth A500 troubleshooting videos, I can recommend GadgetUK here on KZread, he has a plethora of repair vids for all kinds of faults. :)

@Kholaslittlespot1

Жыл бұрын

@@JanBeta Thanks! There is hope!

My favorite computer will forever be my Amiga 500 I bought in 1988 at the PX when I was in the Army.

@JanBeta

Жыл бұрын

Yes, the Amigas are amazing! Still one of my favorite systems to this day. It was absolutely mind-boggling to see what they could do back in the day (and it somehow still is)!

@dls2684

Жыл бұрын

Ditto, except I bought mine in the Navy Exchange 87. Blew my mind.

Not super ignorant, Jan. Only wrong. The means by which we all learn, if we are willing. Might I suggest: Beware of those who would disguise their intolerance with the false virtue of accusation. Another excellent video, thank you. FWLIW: If this is to be considered a museum piece then minimal intervention would seem best. Recapping? Probably leave it if functioning as long as there is no risk of damage. For myself I'd give it a full, sympathetic, restoration. Maybe no longer 100% original, but as long as it's healthy and any replacements aren't screaming their presence that's a job well done. (eg Replace the caps and the FDD if needed but keep all the Rev3-diagnostic stuff like the dodgy connectors)

@JanBeta

Жыл бұрын

Yeah, I think that's my preferred way to go on. I'll communicate with Stéphane and the community and we'll see where it's going to go. In my opinion, the Amiga should be used rather than stored away and gather dust. There are some museums that let people play with the exhibition pieces so maybe that would be an option.

Colour me impressed! Very satisfying to watch this brought back to life. Thanks for sharing the vid.

@JanBeta

Жыл бұрын

Thanks! Super happy that it was such an easy fix in the end and all the original chips still work fine! :)

YES one hour Jan Beta video! Looking forward to this 😃

@JanBeta

Жыл бұрын

Hope you enjoyed it! :)

I love that your days without an accident board has the USS Defiant and the USS Voyager registries on it, I gather that isn’t a massive coincidence haha

@JanBeta

Жыл бұрын

Well spotted! :D I rewatched both series a while back and absolutely loved them (even more than back in the day when I first watched them on TV).

love working on these old amigas

Great job, Jan! I learnt a lot and I am happy that you saved this piece of home computer history.

@JanBeta

Жыл бұрын

Thank you! I'm so happy that I got it working again! :D

Congratulations on fixing the board with the minimum (but necessary) deviation from the original "museum" parts. I am of course refering to this square IC socket. I vote (as always) in favor of fixing the floppy too, even if that means changing one or two components. Good luck.

@JanBeta

Жыл бұрын

Thanks! Yeah, definitely going to take a closer look at the disk drive. It would be amazing if that could be rescued, too.

Great Video as always Jan. I especially like the use of 'Hunky Dorey' Not used enough these days in my opinion 🙂

If I remember correctly you can run a program to exercise the drive heads . That normally gets them to move to all track limitations. And Speedtest the disco rotation.

Approve: My Rev 3 serial 4013 has the same video bodge on the underside of the board! Also the cut trace and the R ☑️

@JanBeta

Жыл бұрын

Ah, nice! Thanks for letting me know. I guess they did that on all the early boards then!

Kudos to you Jan and all those people who commented with their insight. Great video, great job.

Shout-out to Nico D lol The only guy I know who lives in Belgium who sounds Dutch lol Happy New Year and I hope it's a good one Jan.

@JanBeta

Жыл бұрын

Happy new year to you, too! :)

My original Rev5 Amiga 500 had serious stability issues when I started using it again (around five years ago). I only had to look at it the wrong way and it would crash. A replacement Agnus socket fixed it nicely. I also did some recapping and replaced some other IC sockets while I had it apart. My keyboard is one with a Commodore (Chicken Lips) Key and an Amiga Key as well.

@JanBeta

Жыл бұрын

So yours is an early Rev 5, nice! Yeah, the sockets Commodore used are often a cause for trouble. I’ve had to replace many of them (both in Amigas and other Commodore machines) because they didn’t make good contact. They probably bought the least expensive ones available at any given point. :D

Well done! Nice long video that I enjoyed very much.

@JanBeta

Жыл бұрын

Thank you sir! It was fun to dig in and figure out things. Glad the fun translated through the video. :D

Another great video, Jan. It’s great to see another machine live :)

@JanBeta

Жыл бұрын

Thanks! Super happy I got it working again! :D

As you already have some running A500 - i'll personnaly keep this one as Museum piece :-) - Thanks for this Nice Vidéo

Happy new year! I also had a flashing caps lock LED issue. I fixed that by resoldering the controller chip on the keyboard. Still have the occasional boot where the Esc key is not working though.

@JanBeta

Жыл бұрын

Happy new year! I am going to take a closer look at the keyboard PCB for sure. There might be cracked joints, wonky capacitors etc. At this point I’m pretty convinced that there’s an issue with the board rather than with the connector (which I cleaned meticulously and it seems to be just fine).

Excellent video and work! Thanks for sharing

@JanBeta

Жыл бұрын

Thanks! :D

Hi Jan, great video. Please do not recap since it is working now in nearly original condition. Great work, I’m looking forward on the cleaning video and a shake down with some programs to see if really everything is working well.

Epic repair, great work!

@JanBeta

Жыл бұрын

Thanks! Super happy I got it working again! :)

Il lavoro eseguito e' fantastico,2 video eccellenti.sei il top!!

happy new year Jan !

@JanBeta

Жыл бұрын

Happy new year! :D

Happy new year!! :3

@JanBeta

Жыл бұрын

Happy new year!

Thanks Jan. This has been super enjoyable to follow. I think I had a rev3 in the pile of A500s I accumulated. Unfortunately, I gave it hardly any attention, no idea how early it was?😬

@JanBeta

Жыл бұрын

Thanks! The Rev 3 boards are relatively rare, they seem to have changed the production to Rev 5 pretty early on (for FCC approval reasons as far as I understand - the Rev 3 boards produced a lot of noise it seems).

Very great repair. Perhaps you could dismount the diskdrive completely to clean and lubricate al parts where needed.

@JanBeta

Жыл бұрын

I'm definitely going to dig deeper into the disk drive soon (literally). The main board repair took so much time that I couldn't really fit in an exhaustive troubleshooting of the drive. But I'm not giving up on it yet!

Good job mate!

My guess with the floppy: Head misalignment. If the head isn't correctly aligned you can have floppies that boot perfectly and others that don't. More so, if you have floppies made on other not perfectly calibrated drives. This can sometimes ad up to a complete misalignment on the disk side. Regarding the "capacitor problem": You could use a ceramic SMD-Capacitor and solder on some "legs".

@JanBeta

Жыл бұрын

Yeah, I'm going to look into that. My primary suspect are still the caps though but who knows. Definitely going to run alignment tests on the drive to figure that out. :)

@tobiasfenslv6428

Жыл бұрын

@@JanBeta Please do - I have a box with 15-20 glitchy A-500 drives that I would love to fix at some point 🙂. I have heard of the problem with misaligned heads - would love to see a vidoe on how to diagnose/fix this

That’s nuts dood!

Hey Jan, I would goon fixing this beautiful Amiga. What's the deal having such museum piece, but it doesn't work... Also testing of external Floppy Port, Serial and Parallel Port was missing, consider soldering test hardness (it's easy!)... - My last drive (the only one I couldn't fix) had wiggling heads (plastic holder of heads had too much play on the stepper leadscrew, so depending on last move before read, it ended up at different positions and so was misaligned)... - Measure speed of drive (if it's stable or not. Often the reason why you need to replace caps)... - Try to find signal/test point on PCB where the head signals are, and figure out (oszi) if heads are misaligned (low signal strength in general, strange signal difference between tracks or heads, signal difference between disks (which might be ok depending how exact your other drives were calibrated that wrote the disk)... Yes caps might be an issue... - For signal strength and aligned tests always use professionally written disks from factory (original disks). They should be perfectly aligned. (I finally got alignment software... Ami..Alignment System by Free Spirit, software is available, but test disks are rare or expensive) I guess that's my 50cent... Have fun and good luck!

@JanBeta

Жыл бұрын

Thanks for the tips! Very useful for further diagnostics. I'm not giving up on that disk drive yet! :D

This will be my evening movie 😮

@JanBeta

Жыл бұрын

Hope you enjoyed! :D

@Geomanb

Жыл бұрын

@@JanBeta yes very much - loved it!

hey, jan alles gute im neuen jahr und danke für die hartware fxing clips...! de Graukappe aus chemnitz

@JanBeta

Жыл бұрын

Frohes neues Jahr auch! Freut mich sehr, dass dir die Videos gefallen! :)

haha i said YES! when the kickstart logo appeared

Happy new Year Jan

@JanBeta

Жыл бұрын

Happy new year!

The "AddressError" page is triggered by misaligned memory access. You'll note that A0 is an odd number. f80000 is the start of ROM, and it attempted to read E6A1 bytes into that area, likely with a word or long word load. It would be nice of the fault page also listed the source instruction that caused this though. Also a link map file listing all the interesting address locations in the compiled diag rom would be useful.

@jaycee1980

Жыл бұрын

DiagROM does have a bug in the memory test which caused an AddressError when it finishes testing less than 2MB of chip ram. It's not fatal and not a problem.

@JanBeta

Жыл бұрын

Ah, I see. That would explain it!

Hallo Jan, klasse spannendes Video. Was mich im Detail interessiert: könntest du mal deine ganzen Sprays zeigen, bzw. verlinken? Was kaufst du? Welches Reinigungsspray? Welches Schmiermittel? Welches Kontaktspray. Leider sieht man das nicht genau in den Videos. Was genau ist zu beachten? usw. Viele verwenden ja Schmiermittel falsch, z.B. sie nehmen für alles WD40, aber das schadet ja oft eher, eventuell wäre das auch mal wichtig für ein eigenes Video.

Is changing the electrolytic comparators considered a bad thing for keeping the board original? I would personally think it's ok to do because when those does decide to go bad the computer could get damaged beyond repair if left unchecked in a closet somewhere.

46:00 I couldn't hear what was playing from the Amiga, but the filter only kicks in at about 7Khz, so maybe what you were playing wasn't affected?

Good effort Jan! Well done so far. I agree that desoldering PLCC sockets like that is not 'fun' but it was absolutely necessary to replace it. The keyboard connector is a little strange as the cable seems to have a basic DuPont connector on it but the motherboard has a locking pin header. That would explain why the cable will not mate with the board header properly. Was this factory or has someone replaced the keyboard cable connector? Those Varta batteries are a nightmare and the bane of many a vintage computer restorer! As for what to do with the machine now, it very much depends on what is going to happen to it. If it is actually going to sit in a museum or vintage collection and never be used then clean it up as much as possible, put it back together and leave it alone. If, however, it is actually going to be used then recap it. There is no real value in having factory original capacitors. With regards to the disk drive, it is obviously working, at least partially. It may be worth trying to get it working properly but since it is part of a special machine you may consider sending it to someone who has more experience in fixing them rather than trying to do it yourself. Again, for the future, it depends on what is intended for the machine. If it is not going to be used then a non-working drive is not an issue. If it will be used and the drive cannot be repaired then a replacement one would not be the end of the world. Keep up the good work! 👍 😁

@stephanerieppi

Жыл бұрын

As the owner of this machine, I'm seriously wondering what I'm going to do with it. Sure, I'll play with it a bit when I get it back, but (with the exception of the keyboard which is better than anything Commodore has released in the past), it's not really a machine for everyday use. I have other Amiga's that are better, have more memory, a better processor, bug free Gary, etc. As a wise man once said, "It belongs in a museum". As much as I'd like to open my own retro-computing museum, I can't afford it and I doubt it will ever happen. That's why I sent it to Jan in the first place, so that he could show it to as many people as possible and document every aspect of it (which he has done wonderfully - and more than that, he has frankly exceeded my expectations). Once it's working at 100%, working on its aesthetics to make it look like it did when it left the factory seems like the next logical step in the restoration work. And as there has been no yellowing on this plastic - the interior is the same colour as the exterior - and on the keyboard, it will be mostly a matter of cleaning with IPA and soap! Maybe no retrobrighting needed! The caps... not sure. I'd say to extend its lifespan it would be a good idea, but as Jan says in the video, that's for the community to decide. Once it is 100% functional and 100% aesthetically restored, perhaps a final, slightly different "documentary" video could be produced, using all the knowledge gained during the repair and restoration, including the valuable insights found in the comments section of the video series. This would fulfil part of its "museum" destiny. Then, when I get it back, if I am contacted by a (serious) museum in Central Europe (to keep it where it was supposed to be and allow me to visit it) that promises to take care of it (and turn it on for events), I am all for it. Beats waiting for my own death in a box and then being thrown away by my descendants.

@spacedock873

Жыл бұрын

@@stephanerieppi Hi There. Well done in acquiring this machine. 100% working may be a bit of an issue with the floppy disk drive unless it is looked at by someone with in-depth knowledge of repairing these devices. If you wish to go down the museum route I am sure that you would be able to find one that would accept it on "extended loan" so that you still maintain ownership but it is able to be seen by the public. With respect to the capacitors, it also depends on whether you want to take the risk of the old capacitors just starting to leak over time and damaging the motherboard. Much as it is fun and interesting to ask "the community" what to do, in the end it is your machine so you have the final decision. No matter what you decide thanks for letting Jan and other vintage enthusiasts see this piece of history. 😁

@stephanerieppi

Жыл бұрын

@@spacedock873 Hi! Not sure about the FDD, we'll have to see what else Jan can (wants to) do for it. Thanks for the "extended loan" idea, I'll definitely consider it. As for it being my machine, as I said to Jan... I'm just the guy who gave 120 EUR to a local seller three months ago and got incredibly lucky. So, technically, sure, it's my machine. But I don't feel very legitimate about it and I'd like it to be handled more like a community project - I mean, of course, with a definition of community as "people who are legitimately interested in it and have knowledge about it".

Pulling a datecode 7/87 Agnus with a cheapo puller. You have quite some nerves, sir 🫣 Good that you repaired this fine machine appropriately. I for my taste would leave it un-recapped and I would save this drive instead of replacing it with a fd354e, as there is a chance that it is original. And if it is, it would be a very special drive 💾

@JanBeta

Жыл бұрын

Ah, the pullers usually work fine in my experience. :D The socket was pretty worn out, too, so it was easy to not damage the valuable chip. I'm definitely going to dig deeper into the disk drive. I am very much convinced it is the original drive the Amiga shipped with so it's definitely worth trying to rescue it.

There are some disk drive tests you can do on the Amiga Test Kit, they might give you some insight into whats wrong with the drive. As for the caps, I think I would test them in circuit with the capacitance test of the multimeter and only replace anything that looks really wrong. I suspect however that all the caps will ok, I haven't recapped my Amiga 500.

@JanBeta

Жыл бұрын

Yes, I’m going to try the alignment tests for sure. Kind of horrified of aligning disk drives because so much can go wrong (especially with those double sided drives). We‘ll see! I guess the caps in the Amiga are probably all still in spec. I have a fancy ESR meter that I can check them with. I looked at the supply rails with the scope briefly and they all appeared to be super clean so not too worried about the filter caps at least. Recapping would be preventative maintenance mostly, in case the Amiga is going to see some extended use in the future. I guess using a good power supply is more important than the caps on the board though. 👍

You can use MLCC caps as bipolar. They have no ploatrity, so works great as a replacment. Easy to buy till 10uF. I have a big box with them from ebay or ali. handy to have such set.

ach, don't sweat it. Mistakes happen and can be corrected. No need for ppl to throw tantrums over it. ;) Nice rep vid btw. C64 FTW!

@JanBeta

Жыл бұрын

Thanks. I just felt a bit embarrassed about the whole language thing and needed to briefly apologize at least. :D

Hi Jan. Regarding bipolar caps. Look at TDK FG22 Muliilayered ceramics they have 33uF/16V trough hole. They might be useful.

@JanBeta

Жыл бұрын

Yes, that might be an option. I’m looking into ceramic and polyester caps as replacements!

Did you try that disk test on the diag disk once you got the drive to boot from it? I don't know what it does, but maybe it will test the drive speed and/or head alignment, which are the likely cause of the problem.

@JanBeta

Жыл бұрын

I'm definitely going to try that next. I just took a preliminary look at the drive to rule out some common faults yet (fixing the main board took long enough). More diagnostics and troubleshooting coming soon. ;)

Hi Jan, have you tried cleaning the heads and adjusting the risk speed?

@JanBeta

Жыл бұрын

Heads have been cleaned but I didn't do much else yet. I'm going to do some more in-depth diagnostics soon.

I usually watch long videos on X2 speed( i call it Eminem mode 😁) when i realize i am pretty comfortable with the accent and speed.Unfortunately,some KZreadrs are on Eminem mode by default.Being a German guy,he is actually good in English and even uses lots of collocations.👍

@oidadesgibtsned

Жыл бұрын

Have to admit, I like his calm, soothing way of speaking.

@JanBeta

Жыл бұрын

Thanks! That's quite a compliment. I feel like my English got a bit better since I started making these videos a couple of years ago. I find watching my earlier videos pretty unnerving myself these days... :D

Very nice

If you really want it to be a museum piece you should leave it alone (except for cleaning). I agree with Adrian Black when it comes to recapping. Known models like the A1200, yes recap, but not an old C64 or A500, they are not commonly known to fail and cause corrosion (except for any Varta battery, but it's not a cap). 🙂 Recapping increase the risk of lifting a trace or pad the next time it actually need to be recapped, there is no future proofing by recapping. The new caps may be of worse quality. Plus recapping is very boring to watch, plenty of videos that covers that already. Just my opinion🙂.

@j-fharbec379

Жыл бұрын

I agree on this one. Don't recap unless there's a problem. These machines were not part of the "capacitor plague" that affected late 90's machines. I'd leave the Amiga board alone. For the disk drive, I would try to fix it first before replacing it. It's the original drive that came with the machine so it's worth keeping. The solder mask is gone on some of the memory expansion, try to add fresh solder mask on this.

@samuraidriver4x4

Жыл бұрын

All caps go bad from age, however i do agree on if it ain't broke don't fix it. For the disk drive it is definitely an avenue worth exploring.

The same problem had mine Amiga back in the 1988.The service replaced the socket.

@JanBeta

Жыл бұрын

Yeah, the quality of the sockets Commodore used in their machines is legendarily bad. I've seen so many of those fail, no wonder they even failed when they were new.

I get that memory error in Diagrom on every machine where the chip memory is below 2mb. I am not sure if it is just the version of Diagrom I have, but it's like the memory test element is hard coded to test 2mb of chip memory regardless of the actual amount of chip memory you have in you machine. So it seems that once you have exceeded your maximum installed chip memory, e.g. 512kb, the test then fails with an address error as there is no more physical chip memory to test.

@JanBeta

Жыл бұрын

Ah, that would explain it! Thanks!

@al.d9592

Жыл бұрын

Had the same thing. I think it expects 1mb of chip. However, it throws this error at about 480k when you only have 512 installed. So just ignore it

Mine also had that resistor burned. "It worked fine when I used it last...". Turned out, one of the two 3300µF caps was shorted and the other had very low (high?) impedance, a few hundred Ohms.

@JanBeta

Жыл бұрын

Oh, might be a good idea to take a look at those caps then. I scoped the supply rails and they looked very clean so it's unlikely anything is as severely wrong with the caps as in your case. Still going to look into that, thanks for the heads up!

When comparing the board seen in the video with my own rev 3 i see that the lower left corner (left of the RAM) is populated on the board you work on but mine (manufactured w27 87) is empty. I wonder if you, or any viwer, know the purpose of that part of the PCB?

@JanBeta

Жыл бұрын

That’s the area where an oscillator is populated on some boards I think. Some have a crystal near the RAM (like the one I’m working on), some have an oscillator close to the Denise chip (X1 and Y1 on the board). Not sure why they did that.

@jaycee1980

Жыл бұрын

@@JanBeta probably pricing options... initially the separate crystal and suitable gate IC to form the oscillator may have been much cheaper than the oscillator cans.

I would have changed the resistor with a 0.5 watt 1 ohm resistor as it would still prevent a new fail as it would endure short surge without blowing as fast while still doing the same protection

@JanBeta

Жыл бұрын

Yes, I considered using a higher wattage resistor but decided against it to keep the machine as original as possible. Would definitely make sense from an electronics point of view!

Hallo Jan. Bzgl. des Diskettenlaufwerkes. Ich glaube die "alten" Laufwerke können keine HD-Disks (High Density) lesen - nur DD (Double Density)... Im Video kann man leider nicht genau erkennen, welche Disketten du verwendest. Möglicherweise ist die Test-Disk eine DSDD und die anderen nicht?

@JanBeta

Жыл бұрын

Du hast recht, die älteren Laufwerke haben Probleme mit HD disks. Die Testdisks sind aber alle passende DD disks, die in meinen anderen A500 problemlos laufen. Das ist also hier nicht das Problem.

I don't know for sure but the switch on the side of the Amiga casing looks like it probably was used for turning the memory expansion on and off. My first thought was some kind of ROM switcher (which makes sense as you could do more things with later ROM's and then switch back if you had compatibility issues) which has since been removed but the fact that you had to dig through your parts bin for a jumper makes me feel that it was probably for the memory module. Why you would want such a function is beyond me though as I have never heard of any Amiga software that objects to a 0.5 MB memory expansion.

@stephanerieppi

Жыл бұрын

When I received the machine, the cable for this switch was actually connected to the pins where Jan placed a jumper. This was a very common mod at the time (I didn't know anyone at the time who had the 512 KB expansion without the switch). The reason for this is that a handful of very old games (or cracks?) would not boot if more than 512 KB were detected, for reasons that are still not clear to me to this day. This is now completely unnecessary (these games have since been fixed) but many cases have ended up with an unsightly hole. A shame, really. Let's see how Jan will fix this in the probably upcoming aesthetic restoration video. :-)

Seems someone's being Defiant with their Voyager days... :P

@JanBeta

Жыл бұрын

Haha, well spotted! :D

I confirm that the cut trace and bodge for the video hybrid on the back side is present on my rev 3 motherboard.

@JanBeta

5 ай бұрын

Thanks! That is very good to know. So it indeed seems to be a factory mod in these early revsion A500s. :)

I have a gut feeling its the caps in the disk drive. I have resurrected a few that either refused to read or were very intermittent by recapping them.

@JanBeta

Жыл бұрын

Yep, I think that might be the issue, too, from my experience with these drives.

@alex1520

Жыл бұрын

@@JanBeta I am surprised its such a common failure point with the amiga disk drives and not just the built in drives too, I have repaired external ones with the same treatment, caps... Funnily enough I remember repairing my first drive and when looking at the caps they looked fine, no bulging, nothing oozing from the bottom of the caps that the naked eye can see, but as soon as the soldering iron started to heat up the capacitor legs, there was that familiar smell of rotten fish that the electrolyte gives off as it gets hot, knew it was caps right away at that point. Have you considered getting an ESR meter or the capacitor wizard unit at all, these help a lot.

@JanBeta

Жыл бұрын

I have a fancy ESR meter actually. I’m going to try to measure the caps in the drive in-circuit.

Agnus-scracthing by Dj Beta!!! lol!

Hallo Jan, wäre schön wenn du dann mal ein Update gibst ob das Laufwerk wieder funktioniert nach dem Kondensatortausch... habe ähnliches Problem bei meinem alten Chinon FB-354 Rev. A DANKE!

@JanBeta

Жыл бұрын

Hi! Ich hatte noch keine Zeit, weiter am Amiga-Projekt zu arbeiten, habe aber vor einiger Zeit schon mal ein Video zur Reparatur von Chinon-Laufwerken gemacht: kzread.info/dash/bejne/fYOfvM1pgsrHgKQ.html Vielleicht hilft‘s ja!

@j.t.4255

Жыл бұрын

​@@JanBeta Ja, danke, das habe ich mir schon angesehen :) ... ich denke, ich werde die Kondensatoren (großen Elkos) tauschen, mal sehen, ob es dann die Disketten wieder liest... klicken tut es ja, es fängt halt nicht an, die Diskette zu lesen...

what are you using as contact cleaner?

@JanBeta

Жыл бұрын

Mostly Teslanol T6 Oszillin for the contacts. The other stuff is another product from Teslanol called "Lectro Clean", that's more of a general purpose PCB and component cleaner.

Strangely, my A500 is also a rev.3 but the date code has been removed, and printed as silkscreen on the top side, date 13-87. So a few weeks newer, with a new *factory change (fix) a transistor soldered on U33, which is not on the slightly older PCB. My PCB also has the small soldered jumper, but it is also another path that is disconnected and a wire is soldered from EMI434 to pin 18 on HY1 *I am the original owner, so I know it is a factory modification.

@MitzaMaxwell

Жыл бұрын

Mine also have the resistor

@JanBeta

Жыл бұрын

The transistor is a fix for the GARY timing issues in the early revisions as far as I know. :)

Hi Jan, around 11:40 min marker you talk about the fact that is a resistor between the VCC and chip U4, but my thoughts are exact the same as the comment that was posted under the schematic?! It's a capacitor and not a resistor. Are am I missing something else? Regards, Boudewijn.

@fgaviator

Жыл бұрын

No, the schematic shows an EMI filter with 0,01µF. An EMI filter is a component with three terminals: the two outer terminals are connected through an inductance (with a very low ohmic resistance). The middle terminal is connected to a capacitor which taps to the middle of the inductance's windings. The inductance suppresses current spikes, while the capacitor smoothes voltage spikes. That's what an EMI filter is supposed to do. But for some reason Commodore had an issue with these early PCBs, so they replaced the EMI filter - by bridging the outer terminals with a 1 Ohm resistor (so, using an ohmic resistor instead of an inductance). The resistor now still limits the current on the Vcc supply - but no longer filters current/voltage spikes, like the EMI was supposed to.

@bgeelen2602

Жыл бұрын

@@fgaviator Thanks for you clear explanation. Regards Boudewijn.

Regarding the filter, as I commented on the previous video, it's fixed (always on) on rev3 Amiga 500 motherboards. Toggling the power LED (bit 1 of $BFE001) will not toggle the "LED" filter like it does on later revisions.

@JanBeta

Жыл бұрын

Oh, so the filter is always on instead of always off! I was wondering that. Thanks for clarifying!

Hi, as a collector you want to have an A500 Rev 3. In everyday use it can get frustrating as Rev 3 boards have a lot of cold solder joints. Likewise, joystick inputs can be choppy (oblique jumps up). Guru error messages may also appear more frequently 🤕 ACA500 turbo cards do not work together with Rev 3 boards, be careful here too. The well-known "World of Wonders" intro works fine with Rev 3 and Kick 1.2, but not with Rev 5 and Kick 1.3 🤔 Try it 😎kzread.info/dash/bejne/aoiK1cOKXdypodI.html . Nice video Jan! 👍

@nemesis2264

Жыл бұрын

If I remember correctly World of Wonders required the OCS chipset where as later A500's had the ECS chipset or a mixture of both. I pretty sure I have seen an OCS A500 with Kickstart 1.3 run it with no problem but it was a while back so maybe I'm wrong.

@micv2

Жыл бұрын

This wow- intro was on floppy disks from Carlifonia Games, purchased in the schoolyard of course. No problems with my friend's Amiga rev 3 with Kick1.2. With my A500 rev 5 and kick1.3 the intro was broken. So there were differences between the Amigas A500, I wasn't thrilled.. It's been a long time..😊

There should be a jumper (might be a solder jumper) to swap the memory expansion from slow memory to be fast or chip memory.

@JanBeta

Жыл бұрын

I think they added that for the later board revisions only. The contacts may be there but they are not marked on this Rev 3 board.

Regarding the recapping: do it, but only for capacitors that measure off-values in circuit (as far as such a measurement is possible).

@JanBeta

Жыл бұрын

I have a fancy ESR meter that can perform in-circuit measurements quite well. Might be worth a try.

Usually if you have the beginning of the disk working like with Amiga test disk and not the middle, you have an alignment problem. Try to realign it.

@JanBeta

Жыл бұрын

Good call! I’m going to try the Amiga Test Kit/DiagROM alignment checks and see if that gives me any clues.

Those plcc sockets on the A500 seem to be a common fault

@JanBeta

Жыл бұрын

Yes, very common in my experience. Especially on the Rev 5 and older boards it seems.

Flemish is the dialect of Dutch that they speak in Belgium (wel in Flanders, the Dutch/Flemish speaking part of the country). Not sure what the German they speak there is called as I unfortunately don't speak German.

@stephanerieppi

Жыл бұрын

Trying to settle the question once and for all: Flemish/Dutch is spoken in the north of Belgium, French in the south, German in a small part of the south-east (about 75k people) which is adjacent to Germany. The Brussels Region is even more particular, since Flemish/Dutch, French and a little German are spoken there, but also many other languages, including a lot of English, as the EU headquarters are in Brussels. Only three languages are official, and they are Flemish/Dutch, French and German. The Constitution is available in the three languages. English is more of a "lingua franca" in Brussels.

@milk-it

Жыл бұрын

I used to know a German-speaking Belgian living in the German speaking part of Belgium, and she spoke high German with a northern German accent. I could be wrong, but I don't think they have a Belgian dialect of German. If they do, it would be pretty close to Plattdeutsch I suspect. Correct me if I'm wrong! Danke 😋

@VincentGroenewold

Жыл бұрын

@@stephanerieppi Thanks, my goodness what an important thing wasn't it... it ruined the video. /s /s :) People can be so quick to defend something, who cares.

@Brpwndood

Жыл бұрын

@@stephanerieppi Well, I am going to be facecious by giving you high marks for trying to settle this question, which Belgians can be quite nationalistic about, with trying being to key word. This is a generally accepted description of the language issue in Belgium but far from a definitive settling of the issue once and for all. The reasons include that the Flemish area which that language is spoken extends far south into France in areas to the west. Moving eastward we encounter Waloon, a french dialect and finally into the Province of Luxembourge where Luxemborgish is spoken also. In BXL only french/flemish can be considered native, while a high proportion of other languages are spoken due to presence of international organisations like EU, NATO, multinationals and so forth. Except for few people coming from the Netherlands there is absolutely no dutch-speaking going on in Belguim, that would be flemish, which varies per province. lol. Of course generally most Belgians speak two or more languages pretty well like english, flemish, french, german and Spanish. Unless someone lived there and knows people from all the areas and been there on the ground there is no way for them to know this so they are forgiven haha

The Ramtest or chipmem test... test all the way up to 2Mb, since you only have 512kb chip it will fail.. There is not only you who point this out in Amiga repair videos on KZread. That is normal try the test on a 2Mb Amiga and you will have a full ok test.. if the chipram is good though.

@JanBeta

Жыл бұрын

Oh, the test passed. It just threw me the IRQ errors after it ran through. I think it detects the amount of RAM installed and the memory locations quite well and only tests what is actually installed in the system. At least it should. :D

I thought the old (pre 600/1200) caps were fairly reliable ? If it ain't broke...

@JanBeta

Жыл бұрын

Yeah, the through-hole caps are usually pretty robust in the Amigas. They have a limited life-span by design though so I'm not sure if it's a good idea to just wait for them to fail in the future (which they certainly will at some point).

I’d say recap it so it’s reliable and usable. Electrolytic caps are a wear item. Leaving them in is like leaving the original motor oil in a classic car: it might run just fine but it’s set up for disaster in the future. I don’t think recapping will change its historical value.

@JanBeta

Жыл бұрын

Yes, I came to the same conclusion and carefully recapped the board in the meantime (see the next video in the series). :)

@00Skyfox

Жыл бұрын

@@JanBeta Yep, I watched that video minutes after making that comment and didn't bother going back to change it.

I replaced the battery on exp card with cr2032 never leak

Common theme with this Amiga seems to be corrosion, I suspect theres some more lurking in a hard to see place thats giving you the keyboard issues

@JanBeta

Жыл бұрын

Yeah, I'm going to take the keyboard apart in the next episode of this series. I suspect the issues can be resolved with lots of cleaning and maybe some re-soldering of joints on the keyboard PCB.

@alex1520

Жыл бұрын

@@JanBeta Might also be corrosion or a flaky connection somewhere giving the flashing caps lock too, I can only hope its something that simple :)

KS 1.x cant read FFS disks :D use ONLY OFS formatted disks :) or change KS to minimum 2.0 :) and test it again :)

@JanBeta

Жыл бұрын

Oh, KS 1.x can read FFS disks if the driver is installed on the disk. I tried several standard Amiga file system disks and also some games with their own formats. Most failed to read. I don't think it's a matter of the file system.

@cezaryz1232

Жыл бұрын

@@JanBeta yes, y must have L:FastFileSystem, clean it ... JUST try OFS, and tell us.

I'd be in favour of a complete recap. Running vintage electronics on their original caps is akin to running a classic car on it's original oil, tyres and brakes.

@JanBeta

Жыл бұрын

Yeah, the electrolytic caps definitely have a limited life-span. I guess it depends a bit on whether the Amiga is going to be used (which I would kind of prefer) or if it's going to end up as an exhibition piece of sorts.

i get guru meditation failiure on my amiga. i dont see that much in these videos

@JanBeta

Жыл бұрын

That’s probably because the Guru is generally caused by software and not the hardware. I occasionally get Guru meditation errors when I use my Amigas but the videos are repair focused mostly so they don’t appear in the footage frequently. ;)

@tankensomteller5713

Жыл бұрын

@@JanBeta ahh, didnt know that :) thanks for the reply

The video gives the impression that that the battery was handled fairly casually. This is about cadmium and cadmium is a very nasty substance: Once in your body it will never get out again and cause difficult to diagnose health problems. Some precautions and words of caution would therefore be in order when filming the removal of a leaked battery.

@JanBeta

Жыл бұрын

Oh, I genuinely didn't know that there's cadmium or any other dangerous substance in those batteries. Thanks for the heads up! I'm going to be more careful in the future!

there, also not meant to be a gap between the connectors on the ram exp.....

@nemesis2264

Жыл бұрын

When I had Amiga's all the ram expansions cards I had left a gap at the connector like that but my accelerator card did not. It depends on the depth of the socket that is fitted on the expansion card but will not cause any problems and is nothing to worry about as long as it is plugged in as far as it will go.

@JanBeta

Жыл бұрын

That is very common with those aftermarket RAM expansions. I guess the connectors were less expensive than the "deeper" ones that would fit the expansion port perfectly. They usually work fine though so it's more of an aesthetic problem I guess.

workbench screen, not kickstart....... :)

@stephanerieppi

Жыл бұрын

@@nemesis2264 Small Nitpick: 1.2 shown here doesn't have any animations. They appeared with 2.0x. :-)

@JanBeta

Жыл бұрын

Debatable! It's the screen stored in the Kickstart ROM asking for the Workbench disk. So I guess we are both right to some extent! :D