Jump to content

Sam Bushman

Members
  • Content Count

    27
  • Joined

  • Last visited

Community Reputation

4 Neutral

About Sam Bushman

  • Rank
    Space Invader
  • Birthday 09/24/1987

Profile Information

  • Gender
    Male
  1. Well, color me "excited". Thanks for all the effort Rey!
  2. Well, I tried building a simple composite mod based on one of the variants of the famous BenHeck mod floating around the internet. After installing it, I lost all video picture. After removing the mod, the lack of video remained. I'm *hoping* I've just damaged the video modulation chip and can just replace it. Without that chip working, no composite mod will work. Furthermore, I don't plan to perform any mod that will disable the use of the Expansion Module #1. My next step now is to order another LM1889 IC chip and install it. Hopefully this will get me back to where I was before my screw-up with the homemade Composite mod. What's really hurting me right now is my own lack of knowledge about what to be looking at or testing to identify the source of my woes. The best I can do at this point is half-educated guesswork :/
  3. Looking at the schematics posted on Console5's Tech Wiki, I *think* I've interpreted it correctly and found the pin on the Video Modulation chip (LM1889) I should expect the signal from Pin 7 of the sound chip to get to (in this case, pin 15 of the video modulation chip). I found there was infinite resistance going from the pin on the sounds chip to pin 2 of the RF Modulator's daughterboard. I soldered a wire connecting C88 to C100 to match the schematic (despite not seeing any obvious traces on the motherboard). After Making this connection, I had a connection between the sound chip and the video modulation chip on the appropriate pins. I still wasn't getting audio on the final RF signal though For funzies, I soldered an RCA cord to Pin 2 (Audio signal) and Pin 1 (Ground) of the RF Modulator daughterboard. I again got sound (just like when I soldered the wire directly to the sound chip). Therefore I can conclude the audio is now making it's way through the ColecoVision's circuitry. I am now suspecting the video modulation chip is the problem. At this point, I think I can confidently perform a composite video mod without other potential problems preventing it from working.
  4. So I'm a dummy. When I disassembled the RF Modulator, I failed to solder the grounding tabs of the top board of the modulator to ground (previously being serviced by the RF modulator metal casing. Once I got the top board grounded, the video became stable. I still am not getting any sound. Does anyone know where I should be looking on the RF Modulator for the sound signal. I assume the signal from Pin 7 should be getting routed to the modulator (and eventually out the RF port) somewhere. My initial following of the leads just piped through a resistor in the RF Modulator area and to C88. Any thoughts on that would be helpful. Thanks for all the feedback so far.
  5. I have done no AV mod. The only modifcations made were to the video RAM and the power switch. I still assume there is an issue with the RF Modulator if audio is not coming out of it, and I'd like to fix it. The video going in and out is also troubling (and all the composite video mods I've seen pull the signal from the modulator).
  6. Hey guys, so a few weeks ago I purchased an "as-is" ColecoVision off eBay. The graphics were all garbled on the display, so I assumed it was either a power or video RAM problem. Being a very novice electronics tinkerer, I figured I could give a go at repairing the console. After replacing the power switch, verifying the power supply was providing the appropriate voltages, replacing the video RAM with the 5v RAM mod, and repairing some broken traces on the RAM bus I got functioning video! However, I am not getting any audio out of the Coleco. I next wired an RCA cord to Pins 7 and 8 on the audio chip and confirmed it is outputting audio. Suspecting a broken trace somewhere between the audio chip and the RF modulator (due to my experience with the memory bus) I used my multimeter to follow the signal from Pin 7 (audio out) along the various hops on the board. Confirming no break between pin 7 and the last point before entering the RF modulator, I removed the metal box from around the modulator, separated the daughterboard from the modulator, and reconnected the board with wires so I may explore inside it. I have found no broken trace or component between pin 7 and C88. The only symptoms I now have are the staticy audio (and no game audio as far as I know), and the video signal occassionaly gives out. I'm stumped as to what the possible issues could be. I've made a YouTube video of the issue in hopes of getting some interesting leads from those on this forum. That video may be found here: https://www.youtube.com/watch?v=ME-nVOafMpA Thank you for any time and advice provided for this.
  7. I was very careful with the decal. Most of the adhesive stuck to the plastic as opposed to the decal. It all went back together fine (although making sure the decal was lined up properly was a bit of a pain. My usual technique for stickers and the like is just to take it slow and to peel large edges at a time (letting the combined tension of the peeling edge's material keep it from tearing). I am considering doing an RCA-out mod on my Voice for video capture (I already have composite out on my Odyssey 2). The Voice is just great.
  8. Right after I posted that last message, I checked my cabled and found the serial to USB cord was not connected all the way. Things work now and I feel a little dumber Apologies for the spam.
  9. Alrighty, so I don't have any change in the attempt to configure the baud rate of the SSC after setting the DIP switches and confirming the card is set to "Terminal". I boot the Apple 2e, press Ctrl + Reset to go to the AppleSoft Basic prompt, press Ctrl+A to bring up the APPLE SSC: prompt, and input 14B. The result is a system beep and ?SYNTAX ERROR. At this point I'm not sure what I'm doing wrong. Any ideas? For documentation's sake, the terminal looks like this: ]IN#1 ] APPLE SSC: 14B ?SYNTAX ERROR ]
  10. Alrighty, so I found some pictures of the jumper block itself and based on those pictures I am going to assume the dot on the top of the block denotes pin 1. Furthermore, I am basing my assumptions on the following diagram: Apple II Super Serial Card jumper block wiring. 1-+ +-16 | | 2-+ +-15 3-+ +-14 | | 4-+ +-13 5-----12 6-----11 7-----10 8-----9 Based on these assumptions, pin 1 should be on the opposite side of the block from the arrow's direction (the indicator of the mode the card is configured to). Based on all that, I believe this card is currently hard wired for "terminal" mode.
  11. So I am working on bootstrapping ADP Pro on my Apple 2e. I am trying to use the serial method of bootstrapping. When I attempt to set the baud rate through AppleSoft Basic, I get a syntax error. Because of this, I decided to look at what the current DIP switch settings were on the card (I got the system recently). To my surprise, I found that the jumper block for the card was missing. Instead, a bunch of the pins are just soldered together (picture attached). I have found a couple diagrams of how the jumper block is wired, however I don't know how those diagrams correspond to either "Modem" or "Terminal" mode (they usually just describe how the numbered pins on the jumper block connect to one another). Could someone let me know what mode this card is currently hard wired to? Also, if there is a reasonable way to get a replacement jumper block that would be helpful. Thanks for your time
  12. Offhand, I don't have any good answers for you. When I got mine, it was missing the coaxial box, so I bought a composite video mod board off ebay (the one I got and love is here: http://www.ebay.com/itm/Magnavox-Odyssey-2-Philips-VideoPac-G7000-A-V-Composite-Video-Mod-Kit-DIY-/181078338355?var=&hash=item2a291c2b33:m:mSCwRzUx9ZsBq4WsG9nui5w).Then again, if you aren't getting color then perhaps some video line on the board is damage and this wouldn't do you any good. If I find any interesting info, I'll post it here.
  13. Done and one is on the way. Thanks for the suggestion That reminds me of how the vine in Pitfall was drawn using the "ball" object on the 2600.
  14. I had bought an O2 with a malfunctioning joystick. Some models' joysticks don't use switches for detecting button presses, but instead have a hard plastic skirt that presses against a plastic membrane and causes contact between conductive material on the membrane. I repaired these joysticks by disassembling the sticks, using a multimeter to determine the problem spots on the membrane, and applying some conductive ink to said problem areas. Ever since, the sticks work fine. Overall, the console is very easy to take apart, I have a lot of fun with the games (short play cycles, colorful graphics, and some interesting history with the developers of some of the games), and there are some cool add-ons (The Voice module, the Chess Module [Videopac only]). Also, there is an easy to install (if you know basic soldering) mod for getting composite video out of the O2. Pre-made boards can be found on eBay.
  15. Very cool. I look forward to hearing about your progress on this. What are you using to get code on the Odyssey?
×
×
  • Create New...