Atari Centipede lands in the forest, audio repair

Centipede audio fix

I bought Matt C’s Centipede from him! Of the classic arcade titles, I think Donkey Kong and Centipede are my #1’s. They’re the games I remember playing as a little kid the most. Both games have cool sounds for the time and were good looking machines. The Centipede machine was close to solid, the big thing missing was sound. Matt had taken a shot at it, but never finished.

I bought a cap kit from my friend Buffett, to recap the G07 monitor while I was at it. Compared to the other monitors I’ve been dealing with recently like Sanwa 29E31S and Wells Gardner K9200 the G07 was a breeze.

On to the sound issue. First thing was fuses were blowing on the AR2 board which is a power supply / audio amp combined. So I needed to tackle this. Nothing looked out of place, everything seemed okay. Threw it in with a new fuse and it blew. I then tried it again and rapidly removed power and felt components. One of the caps was very warm, which seemed odd. I looked at it closer and one of them was installed backwards. Matt had recapped it, but looking at the board everything was right. But two caps were configured in a way that seemed odd circuit wise to me. I pulled up pics of the PCB and sure enough one was backwards based on pictures. But the board has a + screened right in between them both with no -, I can see where this error came from.

Put it back in. Fired it up !!! Oh yea, annnnnnnnnnd. No audio.

Someone had installed a home brew hack to move the volume potentiometer onto the front with a small hole where the sound can be adjusted without opening the cabinet. I decided to split the problem in half, and fed the audio from there to an external speaker. Got sound. So it’s the potentiometer! So I checked sound after it and… it still worked. So it wasn’t that. Huh? Pulled the speaker and one of the copper braided leads going to the speaker was fully missing. Just totally gone. Ordered a new speaker, and a new track ball. Sound was back! And track ball was solid. And it’s now in the home lineup and won’t be leaving!

Thanks Buffett and Matt !!!

Amiga 2000 Motherboard Clean Up

Amiga 2000 clean up

So I got this hit on a wanted advertisement on Craigslist. I was after an Amiga 2000 system to go with the Pangolin QuadMod16 I bought off of someone via Reddit. Oh yea, I forgot to mention, QuadMod16 in the hizzy! As I feared. As I expected. As I somewhat wanted (to save a computer from death.) The A2000 time/date/config battery had wicked it’s corrosive guts into the system board. The system booted though, so I mostly did my best to neutralize it with vinegar and baking soda.

I cleaned things up. The system was very very nicely loaded, including a Toaster, DPS TBC, DPS PAR, DPS s-video to toaster board, 030 accel, fast ram upgrade and more. I replaced the hard drives (one had failed, one was working but crazy loud) with a SCSI2SD. The one trick is the SCSI2SD boots slower than the Amiga so a soft reset is required after power on to get the system to load from the SCSI2SD board.

The toaster works but I have no way to sync up sources, the TBC-IV seems to not work. The PAR works. Most software seems to work via WHDLoad, although one or two guru meditate.

The corrosion inside is fairly bad, and I fear that in the future this system might still fail. The accelerator that takes over the role of the main CPU might be the saving grace. Also, the ISA slots have corrosion on the connectors. Seems like it might be okay, but time will tell.

The monitor will need to be pulled apart and switches cleaned, and the focus is off quite a bit. Probably could use a recap but that seems like a daunting task.

The keyboard restoration is in another post, it took a lot of work.

Overall I’m thrilled to finally have an Amiga 2000 with the proper specs. The QuadMod16 is another project, it didn’t seem to work or the software is locked to the board — I’m going to ping the original creator for some insight. But Amiga is rocking! My 600 suffered a pretty bad issue and I’m having someone else do the repairs. During the process of 2000 restoration I took a stab at two dead A500s I have, and was not successful in anything after a good number of hours of work. I found bad RAM and replaced but past that neither work at all. Oh well.

BeeCard Reader/Writer project

Beecard reader

A work in progress, so far I’ve managed to build a BeeCard reader (writing doesn’t work) around an Arduino Mega (ATMega) and a BeeCard purchased from someone who sells old Atari parts (Atari Portfolio.)

I had tried to use the Portfolio BeeCard (32K SRAM) in my Korg Wavestation however it doesn’t provide the battery voltage on a certain pin therefor the keyboard always rejects it as a low battery.

My attempts to write data to the writable BeeCards I have has yet to work. I’m not sure where I’m going wrong, I’ve tinkered with the various control lines and can’t seem to get a write to happen.

My read ability might of been an accident? But it’s what I needed. A sloppy python script dumps the card to a file. Not sure if I will revisit writing the writable cards.

Halloween – TouchOSC + Pangolin Beyond + FreeStyler DMX + CellDNA/LED video wall

Halloween hit and I wanted to do something cool. The goal was to be able to hit buttons on tablet, and trigger a lightning type effect. I wanted to trigger DMX stobe and LED up-lighting (Color Kinetics) in time with blanking the LED video wall segments and firing off a cue in Pangolin Beyond that contains sequenced static beam shots terminated safely. I also wanted to be able to trigger a few other cues in each program.

Cell DNA allows midi input which is able to switch which cue is playing. However, the laptop I was running it on (that also had the duty of spitting out scraped video over gigabit network to the LED panels) struggled. I didn’t have a ton of time to scale the video down optimally.

FreestylerDMX can talk midi. Beyond can talk midi and OSC directly.

Touch OSC usually targets a single endpoint, so in my case I ended up running the TouchOSC midi endpoint aimed at Beyond, which has a feature of doing midi through. From there I simply shot the output into the rtpMidi utility which then got the commands onto the network as a broadcast protocol and delivered them to both the computer running CellDNA (borrowed from MAGFest) and the one running FreeStylerDMX.

CellDNA was the only thing that had a lot of issues, and that was it drowning in the video codec I believe.

The outcome was a pretty cool looking halloween display that simply wasn’t scary enough. The wind blew away the output from the fog and haze machines often — though some people caught the lasers. And it was cool when kids would straight up ask, “Is that a laser?” Yep.

But needs to be more scary.

Elmco First Class Slushie Machine, Gearbox repair

Elmco First Class Transmission Repair

So this machine is something of a pain in the ass. I decided to pick up a slushie machine before MAGStock, to bring to MAGStock. I didn’t jump on the more expensive Bunn unit and opted for a Elmco unit which was located farther away. The journey to get the machine from Ocean City Maryland was fun, and I visited 5 arcades on the trip. But, so far the repair of the machine hasn’t been the easiest.

For the first post, I’ll talk about the gearbox. In a slushie machine if the slush mix is just water it will freeze. There has to be a certain content of sugar. And when cleaning the machine, or running it it seems like it’s a pretty big risk of it happening. The machine has a optical sensor on the input side of the gearbox so the controller can monitor the RPMs of the motor, but there isn’t an encoder on the output side. If there was one on the output side it could cut power to the motor and save it from expensive damage. But no, they put it on the wrong side.

When I bought the machine, it appears that one side had a cracked gear. The gears are easy to buy, and to be honest removing the gearbox wasn’t too bad! It was made to be serviced, probably because they break easily. So for $60 you can get a new plastic gear and be set!

This fully fixed the machine, until slush mix dripped down into one of the controllers and it died. So that repair is in another post (I’ve cleaned it up but haven’t tested it yet.) Slushie machine ownership is not to be taken lightly, setup and tear down time (and mess) is pretty strong. The bowls sit on a seal and the seal doesn’t always seal so well until everything is cold.

Galaga Arcade Cabinet Bottom Panel Repair

This one is checked off and done, although the pictures don’t show it. This was quite a PITA, honestly.

The place I live had a condensate drain clog. The floor has a drain, but the concrete was graded in a manner that everything flows away from the drain. This led to it getting in carpet, then soaking up into my Galaga cabinet which is made of particle board.

I used Milwax wood hardner and soaked it into the wood really good to stiffen it. I removed the broken soaked bottom panel and replaced it with a cut piece of plywood. It took two tries to get the cuts right, as I measured it wrong on one of the attempts (oops.) Also, given that the wood was flared out a bunch it didn’t go so easily. I added some L brackets, and also lots of pieces of wood glued to the side and bottom. I ordered new leveler feet, although I’m still nervous about having the cabinet sit on the replacement board 24×7. I might just leave it and the new game that is joining it sitting on 2x4s in case the carpet gets soaked again.

Pictures are of the initial removal, I didn’t seem to have any of the replacement in the album and it’s back on it’s feet.

Galaga Cabinet Repair

Image Engineering “DV” laser show decoder to ADAT direct digital idea

This is mostly a documentation post trying to tie together some thoughts.

A few years ago I worked to reverse engineer schematics and operational theory of the Image Engineering DV decoder for video tapes with digital data of laser shows stored on them. These decoders demux 10 DACs worth of data stored on video tape to drive two color laser projectors.

I have a bunch of tapes, and I would like to archive the content before the tapes degrade.

My original research got me to the point where I found the clock and data coming into the portion of the circuit that demuxes it. But I never put a ton of time into getting a microcontroller to decode it since it requires using an interrupt to detect the break in timing to mark frame start — and once I do get the data moved to a computer I need a solid clocked format to store the content and that seemed problematic. (Tying it to a WAV file as sound card captures audio was one thought.)

Then I picked up a ILDA to ADAT converter from DZ/Ed O’Keefe. They’re awesome people from the laser show hobby/industry that make some nice converters. I was originally using modified ADAT to do this operation but wasn’t happy with signal levels, was out to get their ADAT to ILDA box to give me a nice reference to how things should work when I stumbled across the other version. Thinking more about it, and knowing a little bit about the chip in the box I got to thinking…. if I used parallel to serial shift registers in place of the ADCs I could wire the input side to read the data from the DACs in the decoder. The ADAT system (in my case a HD24) would be sampling the data at 48Khz and the DV playback systems runs slower.

Looking into the wavefront ADAT encoder IC, it doesn’t provide all of the clock signals to clock the ADC chips. I found some info on what could be the circuit needed to do the clock dividing:
https://groupdiy.com/index.php?topic=11498.120

In this case their clock is 44.1khz and I would rather run 48khz. Also, since I need 10 channels then two chips have to be wordclocked together and hopefully the ADAT is happy.

To keep cabling limited between the old board and any new board I was looking at the schematic I drew out in the past. It’s been 3 years and it took a bit to get back into it. Data bus + chip selects into something that can store state into some sorta shift register that is compatible with the data output of the ADCs that are normally used to feed the Wavefront AL1041AG chip:
http://www.wavefrontsemi.com/UserFiles/File/AL_Info/Wavefront%20AL1401AG%20OptoGen%20Data%20Sheet.pdf

Pangolin QuadMod32 replacement ribbon cable

A few years ago I picked up a computer w/ a Pangolin QuadMod32 board. This card is an output driver for laser show software from the industry leader, Pangolin. I had a bunch of issues with the card, and managed to work out a deal to buy/swap for a replacement. I own Pangolin’s latest Beyond software which is very powerful and much better so this is strictly a historical endeavor. At SELEM 2016 laser enthusiasts meetup I brought both the luggable Windows 98 machine with LasershowDesigner and an Amiga 500 running the original LSD1000 software. When tearing down I noticed that touching the ribbon cable going to the QM32 board the image was jumping all around. It was obvious that the ribbon cable has issues. On the last digikey order I threw on a DB25 IDC male and female connector, and finally got around to building a replacement cable.

It will get tested next time I break out the laser projector and will report how well it worked. Note, the QM32 is before the ILDA spec so previously I built a converter that takes the QM32 output and converts it to ILDA.

Hopefully one day I will find a QuadMod16 card, which is designed to go in the Commodore Amiga 2000.

 UPDATE 8/01/2017

First off, I had a problem in my converter that is a DB-25 to DB-25 that converts the older QM32 output to the ILDA standard. I had the red – signal tied to shutter, which was where most of my issues with output were coming from. After fixing this, my new cable worked 100%.

Also, I now have a QuadMod16 card as well. Will be making a cable for that to go from the card to ILDA.

Commodore 64 repair, machine #2

So the prior Commodore 64 audio issue had seemed to be resolved, but when I went to test it with an actual demo it didn’t seem to work. Frustrated I figured I should look into the 3rd C64 that was given to me by Matt C and Mike W. It came from the surplus of Grande Junction in VaBeach, but had markings on it like it had come from CHKD Thrift in it’s past.

Originally there was no life on powerup, but then that changed. It was spotty and upon poking around the glass fuse holder was to blame. Reflowed solder on it and it will still problematic, cleaned the fuse and holder and it was still spotty, bent holder to get tighter grip on fuse and that cured it.

Next sympton was pink screen, orange screen, but not working. Searching online I found a bunch of pointers to things I had already tried (voltage checks.) Finally pointers said it might be the PLA chip, so I desoldered the one out of the donor board (#2) that supplied the SID chip for #1, and placed it in the socket of #3. Came to life, and there was sound from the demo loaded from the SD2IEC.

The metal shielding in #3 was way rusted, and bottom plastic heavily stained. So I combined some parts from #2, and wirewheel cleaned the top shield (which acts as heatsink for ICs.) I sprayed it with yellow rustoleum paint and it looks like a sad Tonka truck but it will perform it’s function and hopefully not rust more.

So check mark on a C64 finally. Claude and Tom are printing me a case for the SD2IEC — whoot! Now to find more d64 images.

HES Technobeam case re-foam

Technobeam Case – ReFoam

A number of years ago I picked up 4 High-End System Technobeams from Hard Rock Cafe in Atlanta. They needed a little work, so I fixed them up. I am a fan of High End Systems products, and had owned some Intellabeams prior.

A few years went on and my Technobeams started going to a few events. They would usually get tossed in a large truck unprotected, and given their shape are vulnerable to the plastic heads getting damaged. I didn’t want that to happen so I kept an eye on craigslist. Finally some cases (and fixtures) popped up in nearby Delaware, and I picked them up. The 4 technobeams had a proper home. The case configuration is sort of annoying, as the yoke has to be moved in a position fairly different from the way I normally hang them to store them. But to have a case that allows it to sit elsewhere would take a lot more room, so it is what it is.

But the foam. It was this melty sticky nasty probably open-cell smelly stuff. Mildewish, tacky and gross. It had to go.

Over the weekend I finally got a chance (and some help from Supersoaker and Christian and others) and replaced the foam with fresher closed-cell foam. It’s stiffer, a bit of a tight fit but hopefully the smell will be gone forever. This material was recycled from other flight cases, and we used a Harbor Freight hot knife to cut it. I see it as practice for when it’s time to make custom foam to hold all the flat panel TVs for MAGFest.