Post by Tom Maneiro on May 11, 2010 20:42:47 GMT -5
Having somehow learned how not to fry the soldering iron, i decided to do some manteinance and modding to my stock Model 1 NTSC Genesis, so i will log my adventures (and potential nukes) on this thread.
First things first: my TV has stereo audio inputs, but my headphone jack was broken (i actually tried to "unplug" it a long time ago, but the pins on that cable are directy soldered from the cables to the PCBs, so i ended ripping it), so i had to survive all these years with crappy mono. But no more! Now the headphone PCB is socketed And i got my stereo BACK! (BTW: fuck emulators - the real deal is a MUST)
(This was my first time soldering a pin header, and finally i learned that the desoldering braid is only good for breaking bridges, not for desoldering ICs and other parts Fortunately, i also got a cheapo analog multimeter - really handy gizmo - no sloppy soldering for me)
Having fixed the audio, now was the time to have PROPER video. My Model 1 didn't came with any AV cable, so i had improvised one with a 32X AV patch cable, staples, some spare RF cable, a couple of crappy RCA plugs, and lots of electrical tape. Extremely hacky, very filmsy, but it did the job... But i wanted my patch cable back, and having no money for purchasing a proper AV lead or even new plugs, i scavenged in my parts box.... and found the following:
- A 5-pin DIN plug from a old AT keyboard. It fits on the AV port of the M1, and has the required pins for ground, video and mono audio.
- An AV cable from my digital camera: 3.5" to RCA A/V 3-lead cable. You can find these for almost nothing on any electronics store.
- A 3.5" female audio plug from some random PCCHIPS motherboard audio bracket, with some ribbon cable still attached to it - big time saver!
Then...
After some probing, shaking, soldering, and lots of electrical and packing tape (i'm not Benheck, so i don't have hot glue ), here is my finished "adapter":
And with the camera AV cable attached...
You may ask "what's up with that brown/black thingy that looks like a dongle on the red plug? Now here comes the interesting part: the 3.5" plug on this cable has 3 rings plus the tip. The innermost ring is GND, then the other two rings are the audio signals, and the tip is the video output. Sadly, the 3.5" socket from the PCCHIPS soundthingy don't reach that innermost ring, so the cable was lacking a ground path. Since it was impossible (for me) to mod the socket, and i didn't wanted to hack the camera cable at all (hey, i STILL use that camera from time to time), i had a brillant idea: bridge the unused red audio lead with the plug shielding (the Genesis AV port is mono, not stereo, and on a M1, you are already taking the stereo from the headphone jack), providing the required grounding. I took a broken RCA->3.5" adapter, bridged the tip with the ring, and created a nice "terminator" (a-la-SCSI). It does the job, and whenever i need to use the camera, i just remove the terminator and plug that lead to the TV
I called the adapter "MD-C1" Test time!
My gamepad also required some love: i have a SG ProPad 6 (a really neat pad, with autofire, PROGRAMMABLE shoulder buttons, and a LED display for setup/testing) that had seen better times... now it requires lots of cleanup on the contacts, and had a couple of broken button membranes (B and C - the buttons still work, but the contact thingy is "floating") and the D-pad was acting funky. Here is the sucker, victim of a mercyless button masher:
Teardown time!
I had to sand a bit the contacts - alcohol was NOT enough for cleaning it uo (use fine-grit sandpaper - never enter home without it!), and the D-pad was no longer funky. FYI, this pad uses a custom ASIC (surface-mount "STD KG25", made in late '94), not your typical lame 74HC157. The PCB is built to last, sadly the contacts are very prone to corrode
Finally, the lamest and simplest of all mods: changing the LED! No Genesis mod is complete without the obligatory LED swap. Blue/white LEDs are all the rage these days, but i didn't had one of those on my stash. In fact, i only had one LED that fits on the Model 1 (without case modding): a green LED. It actually looks nice, and it's MUCH prettier that that boring Ninten-doh red LED:
Well, everything is working nicely for now...
Next stage:
- Region switches (no need for now, but SOMEDAY i will have to get a flashcart)
- Integrated AV plug - no more funky/hard-to-find DIN plugs or a gazillon of cables on all holes
- OVERCLOCKING, YEAH!!!
Now, some questions:
- Is that internal metal shield really needed? Look, FCC does not mandate over my house, and my shield is way too rusted (not mentioning that it's also full of sharp edges... and you know that rust + sharp edges = nasty diseases if you get cut). Could i just get rid of it without harming my Genesis or causing weird interferences? This is my shield.
- I also want to kill the RF box (i could use that space for something more useful, like a custom AV port or something). How many pins/parts will i need to desolder? Will the Genesis keep working without it, or is some rewiring needed after nuking that crap?
Finally, some random pics of mein American MegaDrive(tm):
- Here is how you test your console using the Robocop vs Terminator cart:
1) Do your A/V cables and mods
2) Insert cart
3) Enter sound test and put your favorite tune
4) Poke the cart (just touch it a bit)
5) Fax the crashdump to +1-714-833-8717 while the music keeps playing
(I wish that BasiEgaXorz could do nice crashdumps like that... WEIRD ERROR MAN!?)
- My (unused) 32X. Want it? It even has the L@@k-RARE M1-M2 AV patch cable... Still want it? Get me some $$$$
- HELLOMOTO!
(MC68000P8 POWER! - no shitty un-overclockable Signetics crap)
See ya later... need to do some Vectorman first
EDIT: Moar picz here: media.tsdx.net.ve/workbench/genmod/
First things first: my TV has stereo audio inputs, but my headphone jack was broken (i actually tried to "unplug" it a long time ago, but the pins on that cable are directy soldered from the cables to the PCBs, so i ended ripping it), so i had to survive all these years with crappy mono. But no more! Now the headphone PCB is socketed And i got my stereo BACK! (BTW: fuck emulators - the real deal is a MUST)
(This was my first time soldering a pin header, and finally i learned that the desoldering braid is only good for breaking bridges, not for desoldering ICs and other parts Fortunately, i also got a cheapo analog multimeter - really handy gizmo - no sloppy soldering for me)
Having fixed the audio, now was the time to have PROPER video. My Model 1 didn't came with any AV cable, so i had improvised one with a 32X AV patch cable, staples, some spare RF cable, a couple of crappy RCA plugs, and lots of electrical tape. Extremely hacky, very filmsy, but it did the job... But i wanted my patch cable back, and having no money for purchasing a proper AV lead or even new plugs, i scavenged in my parts box.... and found the following:
- A 5-pin DIN plug from a old AT keyboard. It fits on the AV port of the M1, and has the required pins for ground, video and mono audio.
- An AV cable from my digital camera: 3.5" to RCA A/V 3-lead cable. You can find these for almost nothing on any electronics store.
- A 3.5" female audio plug from some random PCCHIPS motherboard audio bracket, with some ribbon cable still attached to it - big time saver!
Then...
After some probing, shaking, soldering, and lots of electrical and packing tape (i'm not Benheck, so i don't have hot glue ), here is my finished "adapter":
And with the camera AV cable attached...
You may ask "what's up with that brown/black thingy that looks like a dongle on the red plug? Now here comes the interesting part: the 3.5" plug on this cable has 3 rings plus the tip. The innermost ring is GND, then the other two rings are the audio signals, and the tip is the video output. Sadly, the 3.5" socket from the PCCHIPS soundthingy don't reach that innermost ring, so the cable was lacking a ground path. Since it was impossible (for me) to mod the socket, and i didn't wanted to hack the camera cable at all (hey, i STILL use that camera from time to time), i had a brillant idea: bridge the unused red audio lead with the plug shielding (the Genesis AV port is mono, not stereo, and on a M1, you are already taking the stereo from the headphone jack), providing the required grounding. I took a broken RCA->3.5" adapter, bridged the tip with the ring, and created a nice "terminator" (a-la-SCSI). It does the job, and whenever i need to use the camera, i just remove the terminator and plug that lead to the TV
I called the adapter "MD-C1" Test time!
My gamepad also required some love: i have a SG ProPad 6 (a really neat pad, with autofire, PROGRAMMABLE shoulder buttons, and a LED display for setup/testing) that had seen better times... now it requires lots of cleanup on the contacts, and had a couple of broken button membranes (B and C - the buttons still work, but the contact thingy is "floating") and the D-pad was acting funky. Here is the sucker, victim of a mercyless button masher:
Teardown time!
I had to sand a bit the contacts - alcohol was NOT enough for cleaning it uo (use fine-grit sandpaper - never enter home without it!), and the D-pad was no longer funky. FYI, this pad uses a custom ASIC (surface-mount "STD KG25", made in late '94), not your typical lame 74HC157. The PCB is built to last, sadly the contacts are very prone to corrode
Finally, the lamest and simplest of all mods: changing the LED! No Genesis mod is complete without the obligatory LED swap. Blue/white LEDs are all the rage these days, but i didn't had one of those on my stash. In fact, i only had one LED that fits on the Model 1 (without case modding): a green LED. It actually looks nice, and it's MUCH prettier that that boring Ninten-doh red LED:
Well, everything is working nicely for now...
Next stage:
- Region switches (no need for now, but SOMEDAY i will have to get a flashcart)
- Integrated AV plug - no more funky/hard-to-find DIN plugs or a gazillon of cables on all holes
- OVERCLOCKING, YEAH!!!
Now, some questions:
- Is that internal metal shield really needed? Look, FCC does not mandate over my house, and my shield is way too rusted (not mentioning that it's also full of sharp edges... and you know that rust + sharp edges = nasty diseases if you get cut). Could i just get rid of it without harming my Genesis or causing weird interferences? This is my shield.
- I also want to kill the RF box (i could use that space for something more useful, like a custom AV port or something). How many pins/parts will i need to desolder? Will the Genesis keep working without it, or is some rewiring needed after nuking that crap?
Finally, some random pics of mein American MegaDrive(tm):
- Here is how you test your console using the Robocop vs Terminator cart:
1) Do your A/V cables and mods
2) Insert cart
3) Enter sound test and put your favorite tune
4) Poke the cart (just touch it a bit)
5) Fax the crashdump to +1-714-833-8717 while the music keeps playing
(I wish that BasiEgaXorz could do nice crashdumps like that... WEIRD ERROR MAN!?)
- My (unused) 32X. Want it? It even has the L@@k-RARE M1-M2 AV patch cable... Still want it? Get me some $$$$
- HELLOMOTO!
(MC68000P8 POWER! - no shitty un-overclockable Signetics crap)
See ya later... need to do some Vectorman first
EDIT: Moar picz here: media.tsdx.net.ve/workbench/genmod/