Commodore Amiga A500 Repairs Part 4 (White Screen / Bodge Mod / Terrible Floppy Drive & More)

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GadgetUK - Retro Gaming Repairs & Mods

5 жыл бұрын

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This time a look at a rev 5 Amiga 500. This one has a few faults, some of which are only discovered later.
Part 1 - • Commodore Amiga A500 R...
Part 2 - • Commodore Amiga A500 R...
Part 3 - • Commodore Amiga A500 R...
#commodore #amiga #repair

Пікірлер: 104

@GadgetUK164 5 жыл бұрын

As per my comments in an earlier part - the NTSC version of the 500 would have shipped with an 8370 initially. Eventually the 8372A / 8372 was fittted to later boards. FB354 - Floppy button 3D model from Tormentor22 on Thingiverse - www.thingiverse.com/thing:3166315 You can get it printed from Shapeways or somewhere else that does 3D printing. You just upload the .stl file. When asked for the measurement settings - it's in mm.

@thomassmith4999 5 жыл бұрын

There's a Rev 3 and Rev 4 (very rare). The first Rev 5's where mid/late 1987, the mechanical keyboard was last used in Late 1987 (early Rev 5). All rev 3s and 4s should have the mechanical board.

@d0nKsTaH 8 ай бұрын

God this looks like my old "Revision 3 style" board... if it were Rev 5 and somehow I forgot that detail.... I sold mine on ebay more than 10 years ago (as recent as 2013 but possibly even before that.) I know mine had attempts to add jumpers on the pads near the Agnus (or ROM?) and the expansion bus so I could use the A501 as CHIP Ram for use with an 8272 (1mb version). I don't see any evidence of that. That failure put that board into a "for parts only" status... the Crystal was removed in hopes to use that as an 020 Crystal I had.... That failed because the M-tec i-020 board only allowed the crystal to use for the 881/882. So my 25mhz 020 purchase was wasted. I know I didn't socket anything on this board so that audio ports hack wasn't anything of mine :P Maybe I'm looking too hard to try and see if someone's repaired my old stuff LOL and made videos about them. But that floppy does look close... lol That and all the corrosion on the RF shield... I guess people get their grimy hands all over everything. Use a Coke Cola to scrub it ... that should fix it. Along with some Chrome paint and sealant. Same can be applied to that floppy drive casing. Coke and steel wool to clean with :D I'm gonna try and dig up my old pictures.. I got an idea where they are just can't get to them atm. If I do I'll have photos of all three A500's I sold (different revisions) including the last one I got, an A500+ btw that OSC is definitely a PAL OSC. It has lower frequency than a NTSC one.. KYO as well. Completely different than the one I sold which was present... but left unconnected.

@doctorsocrates4413 5 ай бұрын

I think commodore usually only gave their machines a 6 year life span at most...it's marvellous that here in 2024 they are still being used...great video and i love what your doing...best wishes.

@retrolane3481 2 жыл бұрын

Yes it's weird alright to have missing pins, I just brought a 500 plus and successfully removed battery from board,saved! zero damage thank god, your youtube channel is top notch educational

@GadgetUK164 2 жыл бұрын

Thanks =D

@tahustvedt 4 жыл бұрын

I bought myself an Amiga yesterday. After watching all your videos I almost hope it's broken som I can have some fun troubleshooting and fixing it.

@georgelea4297 5 жыл бұрын

its Sunday everyone's gone out, so I'm having breakfast enjoying another one of these great videos thanks Chris

@sweetlilmre 5 жыл бұрын

Gadget and the case of Paula's missing pins. Sounds like a Famous Five novel 😂

@GadgetUK164 5 жыл бұрын

LOL =D

@wolvenar 5 жыл бұрын

Thank you for another great vid. I learn more tricks from you and your followers all the time. I've been in the field electronics of as hobby and jobs since the 1980s, and yet I am still learning new things.

@GadgetUK164 5 жыл бұрын

Thanks =D I am always learning new things from the comments too!

@sethrd999 5 жыл бұрын

Great Fix on this one over all, I got my A500 around mid 87, most of the other Amiga's that friends had were all kickstart 1.2, mine was 1.3 ECS from OCS. I removed the shielding on the side edge connector ( upper ) due to heat ( alot of it ) with my Action Replay 2 in there. I did have an A501 in the trapdoor slot also. Later I did have the floppy button ( thin ) arm snap making it useless, but a friend had a number of spares that sorted that out. One other thing that did happen that made me have to dive back into the case was the Joystick (1) connector pushed in, this required some interesting maneuvering to get it to push back in and slide all the pins back out level so to make a good connection.

@GadgetUK164 5 жыл бұрын

Thanks =D Yes, I remember fixing a few Amiga mouse ports over the years! Not sure what happened on some of the early models, but as you say, pins got pushed back somehow - and broken off on occasion.

@MRMIdAS2k 5 жыл бұрын

Sarcasm returns, we like that. (We is probably only me, but whatever, more of it please)

@Four_X 5 жыл бұрын

Top video Chris, with the case being in a poor shape this Amiga 500 might be a good candidate for a case mod and gotek drive install. looking forward to part 5 bud.

@AdamSommer70 5 жыл бұрын

Another great Amiga video, can't wait for the next part!

@GadgetUK164 5 жыл бұрын

Cheers =D

@d0nKsTaH 8 ай бұрын

One more thing I noticed for info sake to others reading... That resister you replaced... I've seen that same resister burn like that on MANY A500 boards... same one... That's from someone hot plugging in/out a printer or whatever while the machine is on. A huge no no.... A part of me wonders if they (Commodore) use an appropriate gauge resister or if they should have had something stronger. But either way the cause is most likely a careless owner thinking he can just plug in stuff (or remove) something while the machine is "ON". its a good defense in a way in which maybe that'll go (like a fuse) rather than an important chip

@jaycee1980 4 жыл бұрын

In addition to audio and disk control, Paula is also the interrupt controller. If Paula doesnt generate any interrupts, the self test will hang.

@GadgetUK164 4 жыл бұрын

Thanks! I never knew that!

@dedr4m 5 жыл бұрын

Great repair series.... Glad to of found them as it helps I know what to look out for when I goto test my A500+... I'm currently working on an A500+ where the datapath is near obliterated by the leaking battery.... Before finding the A500+ for £10 at a bootsale with a box of disks, PSU, mouse and RF box (To connect to areal of a screen), I did find an amiga A600 in a public bin on some industrial estate.... Unfortunately the keyboard traces were corroded away.... At the time it was in the way at work as they wanted tidyneddfor a customer visit and I foolishly chucked it out assuming beyond repair... If I had kept the A600, I'd of modded that board into the A500 case and used the A500 keyboard (by modding the A600 PCB to accept the keyboard).... Well, at least the A500+ board is keeping me busy for now.

@GadgetUK164 5 жыл бұрын

Amazing what you can pickup on boot sales lol! I think one of my earlier 500+ repairs was picked up by my parents on a boot sale for £3 or something lol!

@iamdkk 5 жыл бұрын

Great video - but we did notice you scratched Agnus ;) at least you show people the holes through the back method :) Loved the floppy drive repair!

@GadgetUK164 5 жыл бұрын

Thanks! I've shown the PLCC removal process on part 6 (I think!) should go up soon!

@keithmcgerr3056 5 жыл бұрын

Great video as always more please!

@GadgetUK164 5 жыл бұрын

Thanks =D

@tails64dsntchannel8 5 жыл бұрын

Really need to give my A500 more love, i paid 15€ for it, it has been smashed up but the board was mostly untouched, fixed it and just used it for a while as it was, i might hunt for a case the next few days.

@RetroComputingwithMike 5 жыл бұрын

I really like the level of detail in this video, i don't have an A500 but if i had, and it needed repair, this video would certainly be a great help :-)

@GadgetUK164 5 жыл бұрын

Thanks =D Much appreciated!

@coyote_den 5 жыл бұрын

Cut and trim spare sockets until you can socket the entire chip, solder any broken pins to the socket, then stick the chip+socket in the board socket.

@GadgetUK164 5 жыл бұрын

Thanks, yes - that was what I was originally going to do but decided it would be cleaner to just fix the 4 pins. I have done the technique you are talking about on a SID chip on my channel previously. In that case the pin stub was pretty much none exposed, proving very difficult to solder anything on to.

@Neffers_UK 5 жыл бұрын

It's Sunday, the wife is away at a craft fare, the son is at his girlfriends. Feet up, Gadge vid and a beer. Cracking. Also, bonus mouse poo! Edit; Now to watch the rest on Paytreon :)

@GadgetUK164 5 жыл бұрын

@GameTechRefuge 5 жыл бұрын

Nice repairs Gadget. Bricked a PC floppy drive recently trying to remove a jam near the T0 sensor. Fixed the mechanical issue/jam but the head alignment is way out now. Without an alignment disk, a scope and the technical docs for the drive its a brick. 45:54 Lesson learned the hard way .

@GadgetUK164 5 жыл бұрын

Thanks! What a shame =/ Some drives are certainly easier to work on than others! These Amiga drives are bullet proof imo. I must have fixed 12 of these in the last 2 years so far I think (2 or 3 more coming up on various vids).

@zxkim8136 5 жыл бұрын

Nice vid Chris 😁😁😁 Kim 😁😁😁

@jochenblacha7241 5 жыл бұрын

Gadget: "This gonna be the shortest repair in the world" Me: You missed the burned up resistor near the external floppy connector so far... ;-)

@GadgetUK164 5 жыл бұрын

I spottted it lol =D Took me a while though - I was fixated on other things!

@104d_3rr0r_vince 5 жыл бұрын

Common problem that burned resistor near ser/par. Seen that before :-/ Also tried to repair a friend's A500 with this kind of keyboard, 2 tapes. Changed everything but nothing positive. We then just replaced it.

@vix_in_japan 5 жыл бұрын

Yes there was the Rev 3 before this and there are a few rare rev 4s in existence. Motherboard itself I think had 2788 silkscreened on it above the Rev5 :)

@Plan-C 5 жыл бұрын

Good stuff. Another real charmer to repair 🤣

@GadgetUK164 5 жыл бұрын

Thanks mate =D

@d0nKsTaH 8 ай бұрын

23:37 this is where Flux and a pair of helping hands grips would have come in handy :D

@GadgetUK164 8 ай бұрын

The solder contains flux! You can see it all around the pin (wet looking). It was oxidised in a way that no flux would help.

@FernandoelChachi 5 жыл бұрын

I told you about how ChipQuik behaves. I won't tell you that it works better here than there for you... LOL. It depends on many things and in your case you've seen something rare: You couldn't solder anything to some pins on the socket... but later you could solder the pins to the inside of them. Come on, it's the same metal on both sides so something very extrange there... In my case (your same problem with broken pins on a chip) I could use a socket and solder new pins and cutted ones all together using ChipQuik as I told you. And the metal parts to join are very separated and ChipQuik helps and that's what I'm repeating here.

@GadgetUK164 5 жыл бұрын

Sorry, I am not following you? I used a few different types of flux here - including chipquik flux and could not solder onto the face side at all. The outward facing side of the pins would not solder at all - as shown on camera. However, the inside would - using the same fluxes.

@gamemaster2618 5 жыл бұрын

Lovely video . Sad for Paula ... she didn’t do anyone any harm .... in order to improve boot speeds to see the 1.3 floppy icon sooner while debugging faults simply put a jumper on the right two pins of the floppy data lead . Tricks the machine into thinking floppy is attached and boots a lot faster . works on all 500s that I’ve tried . Make sure to google which pins I mean, probably a page on Eab or something .

@GadgetUK164 5 жыл бұрын

Thanks! Nice idea! Doesn't it come up saying DF1: Bad on the desktop though?

@gamemaster2618 5 жыл бұрын

GadgetUK164 - Retro Gaming Repairs & Mods well it wouldn’t load the desktop because there isn’t a workbench on the a500 by default unless you have a Ide expansion on the bus fingers .

@GadgetUK164 5 жыл бұрын

@@gamemaster2618 What I mean is - when you boot Workbench lol =D

@gamemaster2618 5 жыл бұрын

GadgetUK164 - Retro Gaming Repairs & Mods how can you boot workbench without a floppy though ? Kickstart screen comes up faster by jumping the two last pins on the floppy header . But in that case floppy is unattached and you don’t have a ide . No desktop or workbench can load lol . Faster floppy screen though !

@GadgetUK164 5 жыл бұрын

@@gamemaster2618 Haha =D Yes, what I mean is - when booting Workbench (after the icon coming up faster) - does it show DF1: Bad?

@csabasanta5696 5 жыл бұрын

Hi, For a chip extractor look into the Wiha picofinish 268.

@Floydzabarber 5 жыл бұрын

Awesome video as usual! I always learn something when I watch your videos. I am curious, you mentioned demagnetizing the head on the floppy drive, how would you go about doing that? I wonder if that would work with a bunch of original Xbox optical drives I have where the magnetization has become so strong that the drives have issues ejecting the tray, even with a new belt. Keep up the great work Gadget!

@GadgetUK164 5 жыл бұрын

Yes, in theory - you could demagentize the metal part on the XBOX drives - maybe go lightly over the magnet part too. That might help there! I may give that a try on mine because both of mine suffer from that (despite new belts). You can demagnetize using a tape head demagnetizer - something like this - www.ebay.co.uk/itm/Analogue-Studio-Tape-Head-Demagnetiser/392296317884?hash=item5b56aec3bc:g:LgcAAOSwLURbaw~C

@Floydzabarber 5 жыл бұрын

@@GadgetUK164 I will definitely give that a try, thanks for the advice.

@andymann1231 5 жыл бұрын

I think pins just dissolve over time in the same way that tin foil just grows around fuses no one ever owns up to it lol

@GadgetUK164 5 жыл бұрын

Haha =D

@amigawarez6795 5 жыл бұрын

nice vid

@GadgetUK164 5 жыл бұрын

Cheers =D

@Mirandorl 4 жыл бұрын

Hello, if you have standard legged electrolytic capacitors, should you be able to test to see what their capacitance is by using a multimeter whilst they are still on the board? I am trying to find out if mine have blown but the meter just "works" for a bit and then return 0L after about 30 seconds. Its the Brymen meter that EEV blog recommends. Sorry I am still learning with electronics and wasn't sure if the legs of the caps are covered in clear resist, making it impossible to just measure off them.

@GadgetUK164 4 жыл бұрын

You cannot easily test capacitance in circuit, because other components are connected to connection points. You can with a good ESR meter check the ESR in circuit, but in either case I would normally remove a capacitor and measure out of circuit to be 100% sure.

@bwack 5 жыл бұрын

Another Amiga 500 repair video!! 😍 😍 I also had broken pins on my VIC-II chip. I took another IC, cut a pin off it put it down in the IC socket together with the VIC-II, and managed to solder the loose pin with the VIC-II pin. It has to be some left of the pin to make it work though. Wait you just did that in this video :) How did you manage to get the solder to stick to the ic pins at around 26:40 ?

@GadgetUK164 5 жыл бұрын

=D The strange thing is I could solder onto the inside of the stubs, but NOT the outside. Something wierd had happened to the other side of the pins. I am guessing it was just corrosion - but even scratching them and using a few different fluxes I could not solder onto them at all - never had that before!!!

@bwack 5 жыл бұрын

@@GadgetUK164 ok. Maybe the corrotion goes deep into the metal since break off...

@GadgetUK164 5 жыл бұрын

@@bwack I think you're right!

@NicolaiSyvertsen 5 жыл бұрын

The shielding on the Amiga is to protect other equipment from EMI coming from the Amiga, not to protect the Amiga in any way. A lot of people just get rid of the shielding and just keep the bottom shielding if any. Basically shielding to please the FCC during certification. You don't see nearly that much shielding on modern electronics where each component is is better certified for EMI and only actual RF components still have metal cans covering them.

@GadgetUK164 5 жыл бұрын

Yes, I realise that - I just like to keep systems complete where I can. It is perhaps an idea to get rid of it though to keep the internals cooler.

@JohnGotts 5 жыл бұрын

Don't want to cause interference with your neighbor's baby monitor. Best to shield these old and noisy devices per spec.

@leebishop6555 4 жыл бұрын

I've got a second hand Amiga 500 but as soon as you put power into the amiga it blows the fuse in the power supply. Any ideas what may cause this to happen, if I just plug the power supply into the wall socket and switch it on no fuse gets blown. Here in Australia there doesn't seem to be anyone about that can actually repair them.

@GadgetUK164 4 жыл бұрын

Most likely a shorted switching transistor in the PSU, or a shorting bridge rectifier in the PSU.

@ingodiekmann8321 5 жыл бұрын

Hey GadgetUK164, Very nice Videos, thanks a lot. I am frommen germany and wonder hat you mean with a liquid you call APA. Is it an cleaning alcohol or something like that? What Tools do you prefer for cleaning?

@GadgetUK164 5 жыл бұрын

Thanks! It's IPA - Isopropanol Alchohol 99.9% I primarily just use cotton buds and paper towel for cleaning things.

@Error42_ 5 жыл бұрын

Yeah. "Use a dip extractor..." they say.... like I did the other day and it slipped resulting in a half extracted chip, the half being one entire side of bent pins still attached and the end pins that were extracted mangled as it slipped over them :-( I'm going back to screw drivers or other flat pry tools for larger chips!

@gamemaster2618 5 жыл бұрын

Error 42 aye dip extractor isn’t really useful as chris said they’re on tight .

@MaverickM1 3 жыл бұрын

Geez, use left amiga key and cursor keys to move the mouse. Shift +amg and cursor keys for large steps.

@GadgetUK164 3 жыл бұрын

Yeah, aware of this! It was more of a case of showing you can do this kind of thing!

@Skauber 5 жыл бұрын

One question, the tune at the orange-y title screen. Is that taken from somewhere? It sounds so familiar, but I can't remember where I heard it and it's driving me crazy. lol. Sounds like it's from something I played on the Amiga when I was a kid... Anyone know where it comes from? :)

@GadgetUK164 5 жыл бұрын

Haha =D I thought the same thing - I cannot work it out either! The 'cracktro' intros often used music from other games. Not sure which one though!

@Crashedfiesta 5 жыл бұрын

Oooh! Samsung keyboard. I probably have a spare function key if you need one (still watching vid). :)

@Crashedfiesta 5 жыл бұрын

In fact, I did a blog about keyboards a while ago. crashedfiesta.blogspot.com/2018/05/keyboards-more-interesting-than-you.html

@GadgetUK164 5 жыл бұрын

Excellent article =D I was unfamiliar with the "Space Invader" model!

@josephneale10215 5 жыл бұрын

👍❤️

@philoffhistree6700 5 жыл бұрын

get a tinning brush for the pins

@GadgetUK164 5 жыл бұрын

What on earth is a tinning brush?!?!?

@projectfanboy 5 жыл бұрын

I suspect someone sold thier duff parts Amiga after fixing their own.

@giuseppelavecchia775 2 жыл бұрын

Chissà chi e' stato a saldare quei 2 orrendi cavetti ai connettori rca dell'AMIGA,non erano neanche cavetti di preaplificazione,ma normali cavi elettrici,peggio di cosi si muore

@hadessuk 5 жыл бұрын

I bought enough cheaper kits that buying an iFixit screwdriver kit meant I could give all of them away and have one kit with everything.

@GadgetUK164 5 жыл бұрын

Yeah, the iFixit kit looks nice! When I can afford one I might get one to review.

@JohnGotts 5 жыл бұрын

Highly recommend it!

@philoffhistree6700 5 жыл бұрын

you know you can use autdacity to get rid of all that hiss you have on your mic

@barryhill3771 5 жыл бұрын

Cant help but feel the Amiga booting is so much slower than what I remember back in the day. I had a few amigas and that is very slow. Would boot different colours screen but very quick. Maybe just me but very sure. Seems to take ages.

@Plan-C 5 жыл бұрын

if you want keycaps printed - send me the .stl

@GadgetUK164 5 жыл бұрын

Thanks!! I managed to source one already!