That power supply label was great! Really added to the build

Anyone else shouting at the screen around 15:00 "Dude, you have your probes backwards!"? Also I could see you sweating through the Australian summer. It's 34 degrees here in Perth today so you have my sympathy.

You totally missed out a great tie-in. With that t-shirt, you needed to insert a "I have the power!" clip from He-Man! :)

Very nice project! Great work!

Good job mate! And such an interesting topic, too. Looking forward to the follow-up.

Great work with the power supply!

I wish I had 1/10th of your skill level here!! Very well done, sir.. that's one nice looking power supply.

Awesome build and the computer should run much cool er now! Love the look of the box with the label!

@MrLurchsThings

3 жыл бұрын

Thanks mate. And thanks for the tip on the 5v fuse 👍

Rectifiers. You mean regulators. 😊

Great job. Love how you rerouted power for this. Well done.

I sold these things when they were new back in the 80's. A fun machine that returned "SN ERROR" everytime you typed something wrong :-)

Great video, I enjoyed that. Thanks.

Fantastic video! I've been meaning to do something very similar for some of my Dragons, so I will probably follow on your exact footsteps. I'm not sure I would have thought of the two fuses, but that's a great touch.

@MrLurchsThings

3 жыл бұрын

Thank bwack for that 👍

You can get all-in-one IEC connector modules with a switch, fuse, and a power light for about £10 and would be *way* safer than having random folks off the internet try to correctly wire up all those safety-critical AC mains components together. IEC socket on the outside, a pair of switched contacts (and an earth point) on the inside.

Absolutely amazing to see the Dragon 32. I actually still have mine from when I was a kid along with all of the cassettes, some cartridges, joysticks, tape player etc. I feel like I need to see if I can get it working again! I'm assuming I'll need an older TV however! 😂

@ChrisThomas-lt8jd

Жыл бұрын

Yes, they only support RF out, or if you buy or make a cable, Composite. I made my own Composite+Audio lead, and connected it to a Commodore 1084s monitor, and it works well. If you want to go retro, try and get an older LCD from 2000-2010 as these can have Composite in. Best thing to do is find a local house clearance company, and let them know you'll buy any TV they have that fits the bill.

It's definitely summer down under. :) Stay cool, sir! :) (thanks for the video too!)

The -5V reg isn't screwed down because the screw connection (and centre pin iirc) is at -5V rather than ground. If you do attach it to the heatsink on a 'working' power board with an original PSU you'll short the -5V line and let the magic smoke out. Oh and the picture quality of the dragon is notoriously terrible. Mine's still rather ghosty/ dot crawly even after a recap and playing with the video trimmers.

@MrLurchsThings

3 жыл бұрын

Afterwards I plugged it into my Sony Trinitron CRT and it’s pretty good. Still noticeable dot crawl, but the rest is way better.

@MrFamousmoose

3 жыл бұрын

@@MrLurchsThings Clearly the Sony's more forgiving of marginal composite signals than modern LCDs and cheapo upscalers :)

@spacedock873

3 жыл бұрын

Yes, the 7905 "floating" catches out a lot of people who don't know what they are doing. To be honest this is almost certainly a design fault but since the -5V is only used for the DRAM memory chips the regulator is not heavily loaded so can get away without being bolted to a heatsink. The other option would be to use a thermally conductive electrically insulating pad between it and the heatsink. Realistically modern switched mode power supplies generate very little heat when providing the amount of power that a Dragon needs so they are absolutely fine inside the case.

Electronics in the shed in Aussie summer. Not ideal. Stay hydrated.

looks great!!! :)

Good job on the safety features, although you shouldn’t have needed that ducktape if you heat shrink tubed the solder points inside. Whether or not you do that on camera, please consider doing that for the mains side at least.

@MrLurchsThings

3 жыл бұрын

I had, but had a couple things of small touch up bits to do this morning so went through and double checked everything.

Nice, this one is in focus too! ;-)

DE-9. The B size is larger.

Loved the video, the label on the PSU really made it shine, great work. I owned a Dragon 32 back in the day. Bought one, boxed about 18 months back. Made a video cable for it last week, and plugged it in (after checking the PSU and internal DC voltages). All was good so flipped it on and it worked! The keyboard was very oxidized on about 95% of its key switches. So used de-oxit + lots of keypresses to revive. Also the picture was horrible, lots of crawling, it that appears to be because the chroma part of the composite was overdone. I dialed it back, and now it's decent enough. Next stage, I also need some way of loading the old programs, and I need to get some peropherals like the joysticks. Really nice to have the Dragon working again :) I wonder if its possible to get to a LUMA / CHROME set of signals on the motherboard? Would be lovely to get LUMA/CHROMA out.

Did something similar for using a PAL A500 to use here in the US with the same power supply. Wondering if I should add a fuse as well now.

I think i prefer the solution where the psu is in the case. Leaving the original DB9 sitting there expecting non-standard voltages just sounds like asking for trouble.

@MrLurchsThings

3 жыл бұрын

It’s now clearly labeled. Also, Dragons are so uncommon here in Australia that the chances of this machine ever meeting and OG PSU are pretty minimal.

@TheTurnipKing

3 жыл бұрын

@@MrLurchsThings I kind of wish there was just an easy power-board upgrade with modern components, to be honest. Take maybe 15v in from a common or garden laptop supply, or one of those new intel 12VO supplies, run it through a few regulators for your 12v, +5 and -5, then take the composite straight back to a DIN or standard composite, maybe take the audio off to the old RF jack instead. The Dragon seems pretty compelling to work on, to be honest.

I wonder when we will get Pt2?

What is the maximum operating temperature of the meanwell unit and how hot does the inside of the jiffybox get?

@Rodville

3 жыл бұрын

I was worried about that especially when he covered the ends in tape. Shouldn't there be a few holes or slits in the outer plastic case for heat dissipation?

@MrLurchsThings

3 жыл бұрын

I’ve had it running for quite a while while building/testing and even in the summer heat it didn’t get warm enough to be concerning.

@MrLurchsThings

3 жыл бұрын

Like I said, I didn’t have any heat issues - but had some time this morning so.... twitter.com/mr_lurch/status/1350596382118215680?s=21

I was legit thinking that was the Apple II clone until the very end when you booted it up ... a brief WTH? and then the realization ... oh yeah, Dragon is Coco, it's Franklin that's Apple! LOL

@Doug_in_NC

3 жыл бұрын

The Dragon isn’t exactly a CoCo clone. Motorola sold a chipset kit based around the 6809, and both Dragon and Tandy adopted it, resulting in very similar and almost compatible machines.

I can't understand why someone doesn't build and sell Dragon 32 PSUs anywhere! We don't all have the skills to solder and not all of use a C64 which has so many options for a new PSU...

Great video! I'm thinking of replacing my Dragon 32 PSU so this will really help... I was wondering if the Mean Well unit would fit inside the case? (I get that you decided not to, but I quite like the idea of avoiding an external box). The 2A fuse on the 5V out is something I'd not considered - cheers!

@MrLurchsThings

3 жыл бұрын

Ive seen it done, but its not pretty.

Another great video! Just one thing you might want to improve for next time - you were a bit zoomed out at the start when working on the circuit board. My tiny monitor and old eyes couldn't really give me as good a view as I wanted.

@MrLurchsThings

3 жыл бұрын

Yup - 30c+ day in the shed = low concentration :( If this heat keeps up I may actually have to clean up my office and shoot these types of things back in there again.

Look like me when I do some diy stuff or repairs/restore job, way too much swearing. But most of the time, i get the job done and don’t hurt myself. So that’s helping in some way I guess 🤷🏻‍♂️

Useless bit of trivia - I remember 10-15 years ago coming across a company in California that was sitting on a large stock of NOS Dragons. IIRC they were selling them off for very reasonable prices and finally sold out 3-4 years ago.

@OzRetrocomp

3 жыл бұрын

That's right... VWestlife made a video about it (I think it was branded the Dragon Tano). Still kicking myself for missing out!

Noticed the desoldering tool you were using as an Anesty. Does yours work fine? I've had nothing but problems with mine and opted to get a yihua which is more powerful imo

@MrLurchsThings

3 жыл бұрын

As long as its kept cleaned and maintained - no prob at all

Hopefully nobody ever plugs in an original power supply.

@MrLurchsThings

3 жыл бұрын

Should probably make a label. Mind you, in the incredibly unlikely case of me selling it, it’d be sold with the PSU.

@ownpj

3 жыл бұрын

Some reverse polarity protection power diodes would cause the thermal fuse in an original psu to pop fairly quickly while protecting the dragon from the worst of the AC input.

@MrLurchsThings

3 жыл бұрын

Label: twitter.com/mr_lurch/status/1350596382118215680?s=21

Neat that you got a Dragon 32! I like your design decision to move the PSU external and provide just DC. It's what I decided to do with the Commodore 1541, making the "1541-DC" here: kzread.info/dash/bejne/Yqhq3NqiZZDHdJM.html

@RetroTechChris

3 жыл бұрын

I love it!

dat shirt

Dude, music is too loud!!!!!!!!!!!!