Welcome, Guest. Please login or register.
Did you miss your activation email?
October 01, 2014, 09:19:17 PM
Home Famicom World Search Calendar Login Register

+  Famicom World
|-+  Family Computer
| |-+  Technical & Repair Assistance (Moderators: manuel, MaxXimus, The Uninvited Gremlin, L___E___T)
| | |-+  New and improved sega genesis model 1.
0 Members and 1 Guest are viewing this topic. « previous next »
Pages: [1] Print
Author Topic: New and improved sega genesis model 1.  (Read 1904 times)
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« on: May 08, 2012, 06:11:47 PM »

copied from my forum:

Lately I've discovered that the cxa2075 in the model 2 genesis isn't generating an image that's as perfect as I thought.  So I decided to revisit messing around with that video circuit in the model 1 genesis.  My modding / hardware knowledge has come a long way since I last worked inside the mdoel 1 so as to be expected the results have been pretty great so far.

I first tried working with my va5 model 1.  I removed all the previous wiring which was a huge mess mostly because it's one of the first systems I ever mucked around with.  After cleaning the internals up I remembered that the model 1 is terrible when it comes to rainbow banding.  I've had a lot of people swear up and down that replacing a capacitor fixes the rainbow issue but nobody seemed to know which capacitor it was.  Earlier I had been mucking around with the model 2 genesis.  I noticed that when feeding the colour subcarrier line from the system into the video encoder that the image stability was much improved but the rainbow banding appeared.  When running the video encoder off of a separate crystal oscillator I didn't really notice any rainbow banding but there was other stability issues with the image.  So this lead me to believe that the rainbow banding is mostly caused by the colour subcarrier line that comes straight out of the vdp chip.

I figured if there was a capacitor to replace that would fix the rainbow issue the capacitor would probably be somewhere near the vdp chip.  Ironically the capacitor that was closest to the vdp chip where the colour subcarrier came out from had been crushed.  I have no clue what crushed that capacitor....but maybe it was gods way of pointing me to the right part to replace.  The cap was a standard 10 uf cap so I replaced it, wired up everything nice and neat, turned the system on, surprisingly there was no smoke coming from it.  Next I attached the cxa2075 circuit into the header I wired up, turned it on, everything worked fine!  First thing I noticed....the vertical bars were pretty weak...pretty much as weak as my model 2.  Second thing I noticed, there was barely any rainbow banding....I don't know if this's because I replaced this one capacitor or something else.

The VA5 vdp outputs rgb that's pretty good but the va6 and later vdps output noticably better video quality.  So today (when my client stops hounding me) I'm going to do the same thing to my va6 and see if I get the same results.  Also with the va6 I'm hoping to get rainbow banding before replacing that capacitor (hopefully it's not crushed) so I can do a before and after comparison.  I'm glad that I got such good results as I love the look of my model 1 megadrive.

*post #2*

As promised I did some farting around today and again had some great results.  I cleaned up my va6, fixed a few things to restore it back to factory condition, and went to work on it.  Installed the cxa2075 circuit and indeed the s-video picture looked a little better than my va5.  The rainbow banding on the va6 was actually just as good as the va5 but no caps had been replaced so I guess that had to do with the cxa2075 circuit.

With the cxa2075 I got a bit of jailbar effect going so I decided to see if I could fix that.  I tried adding a low pass filter to the luma line in the s-video output but that made the bars worse (strange).  I then tried adding a low pass filter in the chroma line and that made the bars weaker.  The filter isn't strong enough to completely get rid of them but it was strong enough to make them not annoying or even noticable unless I'm infront of the tv.  I would have tried a stronger filter but I used my strongest capacitor so I'd need to buy stronger ones to do that.

Anyway here's a screenshot comparison between the s-video from the built in cxa1145 vs the cxa2075 when I bypass the built in encoder.  Keep in mind both of these screenshots are taken from the same system just running different video encoders with different circuits for each.





Strangely adding the low pass filter to the chroma line made the rainbow banding a little worse but since it got rid of the jailbars it's a good trade.  Also the rainbow banding isn't strong enough to be annoying when playing games so no big deal.  I absolutely love the colour encoding of the cxa2075 it has an even bigger pallette range than the cxa1645 which is amazing.

Another thing to take note of is the model 1s which came with a cxa1145 work a lot better when you bypass the built in encoder to a cxa2075 circuit.  My model 2s which came with the garbage samsung encoder are possible to bypass to a cxa2075 but when I plug the s-video output in my capture device from the model 2 with the cxa2075 I had all sorts of strange interference going on.  This's probably because the signals were designed to be fed into a samsung chip instead of a sony chip like the model 1s that came with sony chips.  The bizarre thing is that the model 2 with the bypassed encoder looked fine on my tv, but on my capture device it was insanity.  The cxa1145 based model 1 with the same mod looks just as good on my tv and capture device.

I consider this job done.
Logged

80sFREAK
Sharp C1
*****
Gender: Male
Japan Japan
Posts: 2192


« Reply #1 on: May 08, 2012, 10:56:54 PM »

Well done. But it's a trade and colors looks little bit dull.
Logged

I do not have paypal, facebook, twitter accounts. Don't ask me why.
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #2 on: May 09, 2012, 01:04:41 AM »

Well done. But it's a trade and colors looks little bit dull.


I had the colour strengh turned down in my capture card they aren't dull at all.
Logged

80sFREAK
Sharp C1
*****
Gender: Male
Japan Japan
Posts: 2192


« Reply #3 on: May 09, 2012, 01:41:33 AM »

Ok, i see
Logged

I do not have paypal, facebook, twitter accounts. Don't ask me why.
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #4 on: May 10, 2012, 01:26:38 AM »

Ok, i see

I was actually thinking of adding a resistor to the colour they look a bit strong on my tv but I decided I like them like that so I left it.  Was enjoying some good castlevania bloodlines today the quality is amazing it looks like a vga moniter on my big crt.

Post Merge: May 13, 2012, 12:14:18 AM
Managed to get rid of the rainbow effect I had previously going on.







win!  Cool
« Last Edit: May 13, 2012, 12:14:20 AM by Drakon » Logged

sconley666
Disk System
***
Gender: Male
United States United States
Posts: 159


A rockstar with a Nintendo Fetish!


« Reply #5 on: May 16, 2012, 01:28:42 AM »

That looks amazing Drakon. You always do amazing work, ever since I ran across some of your posts on NA.  I always enjoy seeing what project you are working on and enjoy the tech when you give details. It's a favorite part of the hobby for me. Thanks again for sharing!
Logged

Also sconley666 on NintendoAge
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #6 on: May 16, 2012, 12:22:21 PM »

That looks amazing Drakon. You always do amazing work, ever since I ran across some of your posts on NA.  I always enjoy seeing what project you are working on and enjoy the tech when you give details. It's a favorite part of the hobby for me. Thanks again for sharing!

welcome!  Except I'm permanently banned from NA now.  So I come here and to other forums where the mods aren't mentally retarded.  Also if I were to post this on sega16 where it better belongs guntz would constantly attack me saying it's been done and I'm just copying other people and I use too much hot glue etc etc.
« Last Edit: May 16, 2012, 12:29:43 PM by Drakon » Logged

80sFREAK
Sharp C1
*****
Gender: Male
Japan Japan
Posts: 2192


« Reply #7 on: May 16, 2012, 12:42:35 PM »

That looks amazing Drakon. You always do amazing work, ever since I ran across some of your posts on NA.  I always enjoy seeing what project you are working on and enjoy the tech when you give details. It's a favorite part of the hobby for me. Thanks again for sharing!

welcome!  Except I'm permanently banned from NA now.  So I come here and to other forums where the mods aren't mentally retarded.  Also if I were to post this on sega16 where it better belongs guntz would constantly attack me saying it's been done and I'm just copying other people and I use too much hot glue etc etc.
LOL Looks like we have some refugees Grin Do you really using too much hot glue? Huh
Logged

I do not have paypal, facebook, twitter accounts. Don't ask me why.
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #8 on: May 16, 2012, 05:39:11 PM »

I use more hot glue than other people.  I've had wires pop off just from moving stuff around so I like to use hot glue to keep everything in place.  A lot of my early stuff used excessive amounts of hot glue just to be on the safe side of things but it all worked fine.  A lot of other "modders" liked to pick on me when I was new and complain about stupid things like the amount of hot glue I used.  I never stated that the early stuff was any final product it was a work in progress but all they could do was complain about little cosmetic things.  In fact I know a lot of people who have modded stuff that broke when moved around because there was nothing holding the soldered wires in place.

Another thing I'll get a lot is I'll come up with a new mod where parts of what I did have been done before in other mods.  Next thing I know I get these modding trolls accusing me of stealing someone elses work.  Usually because I take other peoples work and find new ways to use it with really cool results, so cool that people pay good money to hire me to do it for them.  I guess these other modders are jelous that they didn't think of using their own work in such a practical way first.

A lot of other forums *cough* sega16 nesdev nintendoage *cough* let these angry trolls run around saying angry stuff all the time and never do anything about these people.  So I generally don't post my work on those forums.  They all liked to pick on me when I was new to the scene and when I wasn't very good at modding.  Then once I got so good I was making more money from it than they ever did they suddenly started focusing all their hate at me.  That's probably why I was getting accused of stealing someone elses work when really all I did was take their work and improve on it.

It got so bad I had guntz following me around and trolling my work on every forum I posted on.
« Last Edit: May 16, 2012, 05:54:28 PM by Drakon » Logged

sconley666
Disk System
***
Gender: Male
United States United States
Posts: 159


A rockstar with a Nintendo Fetish!


« Reply #9 on: May 16, 2012, 08:37:10 PM »

It got so bad I had guntz following me around and trolling my work on every forum I posted on.

what the fuck is his deal.  You know I actually only have posted on NA once in months.  That place is just so critical and unfriendly.  I know there are people on both,  I don't mean that everyone on NA or DigitPress is a prick, but the overall demeanor of NA has gotten so clique-y.  The whole thing is a pissing contest like "YOU DON"T HAVE STADIUM EVENTS?!? For shame...."  Its like yes, yes I do.  Its called world class track meet and it sucks under either name, hell I have stadium events on an offical multi-cart and the best game on it is MARIO!   I don't know.   It isn't about playing the games at all.  You like to tinker with the tech to make the playing more enjoyable, what the fuck deal is it to other people.  I don't get it.  It sounds like someone needs a life if their internet usage is solely used to make other people feel like shit, or to troll people and cyber-stalk people to be an asshole.  You know I talked to Dain a few times and I think that his attitude and purpose for making the site isn't what it has become.  I actually know a guy local to me who was an original NA member and he sold off his collection and quit using NA because of the way people act.  If you don't spend $1000-2000 a month on unopened games that are VGA graded and go to the Campout then you are a piece of shit and will be treated as such.  POW
Logged

Also sconley666 on NintendoAge
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #10 on: May 16, 2012, 09:15:39 PM »

Yeah that about sums it up I kept posting how stupid all those people were and they went and complained to the biggest @sshole mod in the world.  Mr jerk mod started openly flaming me in a thread so I figured if a mod is allowed to do it then I should be allowed to.  So I flamed back and he was so pissed.  Ironically what I said that finally got me banned wasn't rude at all it's just everyone there is so sensitive.  I agree with you that not everyone on those forums is bad I made a lot of good friends there but all my friends who're on that forum never post openly they just used hidden threads.  I don't get why those good people don't just find a better forum.  All my friends were so sorry for me when I got banned I couldn't care less I hated that forum it's nothing but a complete slime-fest.  And it's not like I made huge business from that forum most of my commissions comes from people on youtube.  The people who hired me from NA were all cheap and whiney and tried to make paypal claims behind my back for delays that weren't my fault which I had already explained.

Then there was assembler games.  On assembler games people were complaining about me converting doom carts into other games.  Seriously...it's doom on the snes....being converted into better games so they can run faster....what's the big deal?  Doom on the snes has good music but there's plenty of other ports of doom that're way better and doom isn't that fantastic of a game to begin with.  All the people on assembler games could do was complain about me sacrificing doom pcbs for conversions instead of focus on what I was trying to do.  I mean there's a reason why people paid 100-150$ for these converted superfx carts and everyone said that they got their moneys worth.
« Last Edit: May 16, 2012, 09:20:54 PM by Drakon » Logged

80sFREAK
Sharp C1
*****
Gender: Male
Japan Japan
Posts: 2192


« Reply #11 on: May 16, 2012, 10:39:23 PM »

*ROFL* Totally, 100% agree with you, guys. Yet, it's hard to be bright, but this is the key of progress and evolution.
Logged

I do not have paypal, facebook, twitter accounts. Don't ask me why.
sconley666
Disk System
***
Gender: Male
United States United States
Posts: 159


A rockstar with a Nintendo Fetish!


« Reply #12 on: May 16, 2012, 10:56:57 PM »

Oh, and god-for-fuckin-bid anyone ever have an opinion there that is contrary to the high school hardcore collectors views.
Logged

Also sconley666 on NintendoAge
Drakon
Twin Famicom
*****
Gender: Male
Canada Canada
Posts: 705


Retro console modder


WWW
« Reply #13 on: May 16, 2012, 11:28:05 PM »

Oh, and god-for-fuckin-bid anyone ever have an opinion there that is contrary to the high school hardcore collectors views.

Haha.  I made some comments about them all living in their moms basement on welfare and nobody there having a job or any money and I got mob flamed.  Seriously they were complaining about my prices which are already lower than they should be.  My prices don't nearly reflect what I should be charging to pay my bills.  I just set my prices at what they are because I enjoy doing these mods.  People who hunt me down from youtube never complain about my prices they all seem to actually have jobs.  Really 150$ isn't a lot of money I know people who pay $1200 a month in rent and that doesn't even include electricity and water bills.  And yeah people at nintendoage always seemed to have to jump all over me when I had a contradicting opinion.  I didn't care that they had a different opinion but they always had to make such a big f#cking deal about it and couldn't just accept that we have different views.  I never went around that forum trying to prove them wrong I just stated my opinion and tried to leave it at that but they really go crazy if you're not part of their retarded cult.

Another thing I posted that got me attacked was how stupid their inflated prices were and how dumb it was to drop crazy money for something just because it's rare even though it's a terrible game.  Even the guy who made the powerpak was super sensitive about anything negative I would mention about his service.  He was acting like people were going to see my posts and nobody would ever buy from him again or something.  I also had a lot of people on those crappy forums threatening to tarnish my reputation and I told them to go right ahead.  I told them that 95% of my clients don't read forums because they actually have jobs and better things to do.  I also mentioned that my clients hunt me down from youtube instead of hanging out in the filth infested flea markets where you'd find the average nintendoage excuse for a human being hanging out seven days a week.

Everyone on nintendoage only cares about making money and trying to scam skilled people like myself for underpriced / free service.  I used to pass on cheap / annoying clients to another guy who I knew would f&ck up their systems and give them the absolute worst service.  Then when the clients all came complaining to me about the sh#t servive and broken consoles I would laugh in their faces and tell them that they shouldn't have cheaped out on me.  I've since stopped associating myself with that other "modder" so now if anyone gives me a hard time I just tell them to f#ck off and do the mod themself.

Post Merge: May 18, 2012, 04:15:42 PM
At the request of someone on my forum I made a demo video comparing the standard cxa1145 s-video mod to the s-video quality from my mod where I installed a cxa2075 and built a decent s-video circuit

http://www.youtube.com/watch?v=6nGTcLCTwM8
« Last Edit: May 18, 2012, 04:15:42 PM by Drakon » Logged

Pages: [1] Print 
« previous next »
Jump to:  


Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!