While working on developing the A2VGA Pico IIc/IIe video cards (not to be confused with the other Apple II video cards with the A2VGA name which work in a completely different way) I had a small project in mind that would be good to have around so as to show off the video cards. I'd been slowly collecting the main components and I figured it would be a reasonably quick build. As it turned out, I was able to knock it over in a weekend (for the most part). No prototype project is complete without issues. However, I was able to get around the few issues that popped up pretty quickly.
I've been looking at using an iPad as an Apple IIc monitor, on and off, for over a decade but my previous attempts were focused on doing this by trying to feed a video signal into a working iPad. This is much easier to achieve now than it was in the past (due to newly available iPad Apps and new hardware) but this time around I had an alternate option. I had a well-used iPad3 in the cupboard whose battery had been stripped out years ago due to it swelling up and cracking open the case. If I repurposed just the LCD screen, then I could produce a more efficient solution with less display lag. As a bonus I would have the opportunity to test out a retina display, since the iPad3 was the first iPad generation to contain one.
The result is iLoveThisMonitor, a repurposed iPad into a funky IIc monitor. It turned out better than I had envisioned (for both the aesthetics and the display quality). The 9.7 inch screen is a nice fit with the dimensions of the IIc and the round corners of the screen/stand don't take away too much from the stying. It's not the best period correct looking solution out there but for the ease of construction I'm happy with it for now.
The iPad case came with plenty of scratches and dings as a result of being dropped a few times. I had no reservations about defacing it to suit my purposes. I could have found a case that enclosed the electronics, but I wanted a quick build and I also wanted the A2VGA Pico to be visible. Reusing the existing iPad case resulted in not having to worry about mounting and positioning the LCD screen in an enclosure. I like how the openness shows the functional parts of the monitor. It gives it an industrial looking edge. Especially when viewed from behind. I've left enough space so that I can easily remove the current VGA cable and use this monitor to display any other VGA or HDMI input.
This is not the first iPad to be repurposed into a monitor. There are dozens of examples online of various custom conversions to get tips and inspiration from. However, in my situation, I wanted a compact solution with an attached IIc video card, and I wanted to see how the A2VGA Pico performed when matched with a retina display. I was not disappointed.
It was difficult to get pictures of the resultant outcome. The iPad screen is very reflective and to get some decent shots of the system I resorted to taking pictures in low light. The IIc comes up ok but the screen background appears as if it is bright and glowing (not dark like it really is). I tried taking shots of just the screen in darkness and although it comes out ok, the photos I manage to get come out oversaturated. I can't get the shots of how nice it looks in person. This is probably due to my inexperience in photography and not having the right tools for the job. I guess people will get to see it when I attend Apple II enthusiast gatherings. If I do manage to work it out then I'll post some pictures at the end of this blog.
Construction:
The first step was to obtain an iPad LCD screen. I didn't need to do anything here except look in my spare parts bin. The well-used iPad was just waiting there, ready to be repurposed. I decided to reuse the case as well. Since there was not going to be enough room inside the case to mount the electronics, they would all need to be mounted externally. I was considering placing acrylic sheets over the top of the electronic boards but then decided they were going to be too much work and not really necessary for my purposes.
The most critical part came next i.e. sourcing the correct LCD controller board. To do this I took the iPad LCD screen's model number (LTN097QL01-A01) and searched online for a matching controller board. AliExpress and eBay are the main sources for these boards. Since LCD screens come with various connections and resolutions it is important to get the right controller. In my situation I came across two controllers that would do the job. The older one was made up of four PCBs (video processing board, LED power supply board, menu push button board and LCD connector board) and the new one was made up of three PCBs (the LED power supply was integrated into the LCD connector board). I chose the newer model. It was more expensive but resulted in having less components to mount.
I connected up all the electronics to make sure I could get a working device. There would have been no point in continuing if this had not worked. At first, I had the backlight working but no picture and no menu. It turned out I didn't have the tiny LCD connector cable in far enough into the adapter plug. This was my first attempt at performing this task. Luckily it did not take me long to work out what I had done wrong and I'm happy that I didn't fry anything.
Once I confirmed that I had a working system, I stripped out as much as I could from inside the iPad case (except for the LCD screen of course). This helped in making the case very light. It also resulted in the magnets being removed which is a good thing since I still use floppy disks with the IIc.
The panel needs to be powered using its own power supply. The video output port on the IIc can supply 12 volt power but it is only rated to 3.6 watts. This is enough for the A2VGA Pico card which consumes 0.3 watts however it is not enough for the LCD panel which uses roughly 5 to 9 watts depending on the brightness level.
It took me a while to work out how I was going to position the components on the case. This included the consideration of where the stand was going to be attached and hence the type of stand I was able to use. Once I committed to a layout there was no going back. The holes were drilled, and the parts started to be attached. Initially I had planned on hiding the menu push button board inside the iPad case but as I connected it up, I found that it did not fit. It may have fit if the switch bases stuck through the case but putting in small square holes into the case sounded like too much effort. I ended up mounting the board on the outside instead. I used polycarbonate screws to attach the PCBs to the iPad case. This made it very easy to trim their lengths. Trimming the lengths was important because there was not much clearance space inside the iPad enclosure.
For supporting the iPad, I picked up a tablet stand from Umart (a local PC supplier). I only needed the base and the arm so the top part was removed. It's connected to the middle of the iPad case via the Apple logo which is comprised of a thinner sheet of aluminium and a bit of plastic/acrylic. It's very flimsy so at some stage I plan on adding in a thicker aluminium sheet to obtain a sturdier fit.
I used a VGA gender changer to join the A2VGA Pico to the LCD controller. However, I didn't end up using this in the final build. This was because I could not find a version of the VGA gender changer that allowed both boards to be facing in the same direction. I ended up building a custom cable instead. This custom cable resulted in some electrical interference i.e. a small wavy pattern. The wavy pattern does not show up when using the VGA gender changer or when using a proper VGA cable. I attempted to fix the issue by adding in an alfoil shield but that did not help much. It's not a big deal but I will try and make up a better quality cable at some stage.
To finish it all off, a custom IIc video port cable was made to suit. I chose a rainbow coloured cable in this instance to keep with the retro look.
Conclusion:
Combining a premium video card with a premium LCD panel has fulfilled my goal of creating something that is going to give me the quality I was after without having use my CRT monitors. I also think the monitor will do a great job in promoting the A2VGA Pico IIc/IIe (the video cards that I have been working on for the past few years). I'm really happy with this build.
Take it easy and happy hacking.
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