Saturday, April 15, 2017

Commodore 64 on Sony PVM 14M1J Monitor

Look what the cat dragged in...
After I confirmed in my last post that the video output of my C64 is actually working fine, I was ready to look for a more permanent video display solution. Since any the original Commodore monitors is hard to come by these days, and even more so in Japan, I had to look for something else.

Being in Japan, though, helped me out for a change. In the retro computing community it is well known that the professional line of Sony monitors, originally used in TV broadcasting and medical applications, are the best option for scanline hunters and retro gamers like me.


I was lucky enough to snag a 14 inch PVM from Yahoo Auction for only ¥6000 plus ¥1400 shipping, while an equal model probably costs you something like 200 bucks anywhere overseas before shipping.

Unfortunately, despite the careful packing job, it didn't quite like the transport and the plastic front bezel got cracked. Nothing a little Duct Tape can't fix and it has no influence on its functionality and picture quality, but it definitely lost all it's resell value.



The PVM 14M1J model has 4 inputs in the back. Two of which are composite, one for s-video and one RGB with sync switchable either as external c-sync or as sync-on-green.

It has 600 TV lines, automatically detects and handles both PAL and NTSC sources, plus has a slew of options to tweak via the on screen display.

More details on Sony's official PVM-14M1J page in Japanese.


All I needed now was a relatively cheap Commodore 64 S-Video cable. I got the one to the left off of Ebay for about 14 bucks. There's always several listings with different connectors (e.g. 1 or 2 audio connectors  although the C64 only outputs mono, s-video and/or composite connectors). No use to go with the lower quality of composite video when the PVM takes s-video, so the choice for me was clear.



And now I have the perfect display option that's arguably even better quality than what I had back in the 80s when I owned an original Commodore monitor.


Wednesday, April 12, 2017

Hunting for a display solution for my Commodore 64

My plan when getting the C64 was all along to make use of my old Eizo E67T VGA CRT that I kept lugging along throughout all my apartment moves for the last 15 plus years. It wouldn't be much nostalgia to slap on an LCD screen after all.
The problem was, the set I bought only came with an RF cable, the lowest quality solution to get video out of the C64. The AV port, though, has pins for both composite video and s-video with s-video obviously being the preferred option:



There's a ton of guides online on how to construct your own s-video cable with just about everyone suggesting to add a resistor on the Chroma line since the signal is apparently not up to specs, too strong, and modern displays would have trouble handling it correctly. I was going to order the parts from China and the guide linked above to make my own cable, but patience got the better of me and I ended up ordering a proper one off of a guy our Commodore Facebook group crowd suggested.
He used high-end connectors and even slapped on a ferrite core to cut out interference. You can generally find good options for $15~20 when searching for "c64 s-video cable" on eBay.

That was step one. The Eizo unfortunately doesn't have an S-Video in, though. Besides the standard VGA plug it has RGBHV BNC connectors but can't handle the 15kHz PAL signal and being in NTSC land here in Japan I had to stick with my Eizo. So I needed to get an upscaler. The online community apparently had mixed results with devices like the one to the right. An "svideo to vga" search on Amazon reveals a whole slew of these things, always the same case, always different branding and ranging from like 12 to 40 bucks.

I decided to go for one somewhere in the middle of the price range hoping it'd heighten my chances for success. It said to handle both PAL and NTSC and came with an OSD to select several different output resolutions/frequencies from 800x600 up to 1280x1024.

 That all didn't help and the result was horrible and completely unusable as you can see on the right. No colors as if it couldn't detect the PAL signal correctly and the still picture here doesn't do the brain shattering flickering it put out any justice either. So I returned it and went for the fancy 40 bucks option, a device produced in Japan with similar features but it certainly looked more high-end and didn't come in the same old casing like all the many other Chinese versions.
Being made in Japan, though, had absolutely no influence and the result was unfortunately exactly as useless as with the other. So back to the drawing board.

 Even though the seller assured me that the unit was tested working, it dawned on me that I never actually saw a correct picture coming from this breadbox. Could it be that the upscalers worked properly all along and that there is a problem with the VIC-II chip or some other issue with the machine itself?

Time for some proper testing then. Unfortunately, the cable I ordered only has an S-Video lead and all the LCD screens and TVs I have lying around the house only have the typical yellow RCA connector for composite video input. This requires some outside the box thinking...
Pin-out diagram shows composite on pin 4 and ground on pin 2. So, some alligator clips, 2 Arduino starter kit jumper wires and an RCA cable later and I had the Frankenstein construction ready to the left here. Then, lo and behold, on my huge LG TV via composite-in finally the nostalgic blue on light blue start screen I've so dearly missed:

Tuesday, April 11, 2017

Commodore 64 arrives, finding modern PSU replacements...




Thanks to my awesome friends and their generous baggage allowance on their trip to Japan, I'm now finally united with my auction purchase and more excited than a little kiddo on Christmas to finally be in possession of my breadbin 64!

Time for some unpacking and testing. The seller ensured me that he powered it up and all was still working fine, so hopefully there won't be any nasty surprises like the dreaded black screen of death welcoming me. Everyone online warned me about the danger of using the original power supply, though, and how it could fry your RAM chips and more. But Japan being on 100V while this PAL box came with a 220V PSU, I didn't have any use for it anyway. I purchased this Y-cable instead that lets you plug in a 9V AC and a 5V DC adapter separately. I already had plenty 5V DC adapters lying around and just ordered a 9V AC adapter from Rakuten.

To power the 1541-II floppy drive was a bit trickier, but fortunately people pointed out that you could get both 5V and 12V DC from old ATX PC case power supplies. I ended up ordered this AC adapter meant to power old IDE disk and CD drives. Sourcing the right 4 pin DIN plug that goes into the floppy drive proved a bit tougher, but some extensive Aliexpress searching revealed the right one eventually too.

That sorts out all the power needs, but getting the video to display in any meaningful manner will be a whole other story, so stay tuned for that...