shmups.system11.org

Looks like you can lift the legs of R2024, R2025, R2026 that are FARTHEST from the micro controller to isolate the OSD RGB, use the empty holes to inject 75R terminated/0.1uF capped RGB. For blanking lift the leg of R2027 that is CLOSEST to the micro controller and inject your 5V into the lifted leg.

Sweet, thanks for the info. So if this works, I can add a mux mod, and if it doesn't I can revert it back to stock? How would I go about testing to see if it works, do I just directly apply an rgb signal to the respective points (from say the DIN port on the Sega Genesis)? Also what parts would I need for the testing phase, just wire, 75ohm resistors, and 0.1uf caps? Sorry for all the questions I just want to avoid any issues.

I think you need to do your own research from here. Please read the Wikipedia page on Scart , (this makes me feel a little sick) read the first post of this thread and check out my mux diagram.

Alright, I'll do that and report back when I can. Thanks. I read in another post involving digital rgb input that only red green and blue will show up and all other colors will be dark/black, is that what I'll see if it's not compatible?

I believe if it is set for digital RGB, if the inputted RGB ever goes over the threshold to be "digital On" you'll get something, otherwise nothing.

hello i hope you guys can help me figure out what the hell im doing.

i have a kv-20s20 and it uses a cxa1870s jungle chip. i had read earlier in this thread that it could not be modded because it is digital well i read that after i started trying to rgb mod it.
i am testing this using a master system and genesis. this tv is odd because i can see the rgb signal on the tv whether i have 5v on the osdblk or not but when there is no 5v the brightness and colors are dim
also i see the menu with or without 5v on osdblk which leads me to believe that the rgb is for closed caption only.

i have been messing with this tv for the better part of a week trying many different configurations but i finally got a decent image after i injected the rgb signal right on the pins of the cc chip so i removed it from that location and injected into an empty header location just before the jungle and tried to simulate the circuit between the cc chip and jungle chip. after experimenting a little more i have a very good image on screen that im happy with.

i have very limited knowledge of electronics but i do know how electricity works and i work on refrigeration equipment so have to deal with high voltages and low voltage control circuits so if you guys could help me understand whats going on here and how i could do it better i would greatly appreciate it. for instance i dont understand what the capacitors going to ground are for in the original circuit, why changing the resistor values on the rgb from the genesis changed color and brightness even though there not ghanging the voltage (im guessing its changing amplitude), or why the sync from the genesis needs a resistor or i just get a black screen.

i drew a diagram of the circuit between the cc chip and jungle chip but the scan is kind of crappy and hard to make out blown up 500% so i could not read the value of some of the components and the values i have could be wrong. there is also some kind of load on the osdblk line after the first resistor but what it is is unreadable in the original diagram. also i imagine that this mod would not work with standard scart cables for these systems seing as they add extra resistors and capacitors in the circuit.

service manual: https://www.manualslib.com/manual/96015 ... 20KV-20S20

jungle chip datasheet: https://pdf1.alldatasheet.com/datasheet ... 1870S.html

here are some pictures of my modifications and the results. thank you.

Modding a 32" JVC D series with RGB possible?

If so any hints where to start?

TB1253AN is the jungle I believe

This is the model




At mikejmoffitt I found your D series modding website http://mikejmoffitt.com/articles/0032-tvrgb.html

What was exact model number? Was hoping you could help me out please.

Thanks in advance

that's a really easy chassis - there is a nice unused PiP header footprint on the board that has your 3 colors and Ys/Ym both from the micro and to the jungle - all you have to do is remove some 0ohm jumper resistors and replace them with 1206 package diodes and then follow the mux chart / diagram in ozlad's sig

I am super new to this.. To be honest kinda of intimidated by the diagram, chart and language as I am not a Electronics engineer.
Always was able to follow tutorials for modding but this seems easy and hard at the same time.

OK so I get the PiP header... It has RGB But Ys and Ym I have no idea what that is.
I read 90% of this entire thread and it seems like the Switch method is replaced with this method your talking about. MUX

So here is where I am confused.

I get the whole Removing 0 ohm resistors. I would have to know which 0 ohm resistor points to remove and replace, I assume These will work for the 1206 package diodes? Basicly I would use my hot air or hot Tweezers to pull the 0 ohm resistors off and solder these in their place?

https://www.alliedelec.com/product/bour ... lsrc=aw.ds

The Diagram to me is ultra confusing.

So I was hoping someone did it already or could explain it in baby steps.. kinda lay it out in a step by step tutorial.

Based on the MUX diagram it looks like more than just a few resistors need to be replaced I see like 5 areas where things need to be pulled and replaced.

So hoping someone can help me out, help me understand this and get it done.

Thanks again

Ys/Ym is the switch pin that makes the jungle IC switch to the external RGB inputs. You use the Mux diagram to figure out which resistors you need to inline with your signal to make the proper video signal levels, in your case 0.7Vpp, which as the OSD has 2.2K resistors in-line, means you should use 300 Ohm if you don't put in the diodes, and if you do, you should use 390 Ohm instead.
In the CRT Collective thread I point out where the resistors should be in your model. If you change them, align the diode with "the line" away from CN002.

Not sure why you aren’t getting horizontal sync when you’re on TV sync but it may be because of the way you wired the sync or because of non standard sync from the Pi.

You won’t get any sync from the AV port until you change the TV to AV channel. Need to get a remote.

This might be a dumb question, but...

Do the modified RGB TVs accept high amplitude RGB from arcade boards (i.e. 2-5v p-p) or do they still only accept 0.7v p-p?

This might be a dumb question, but...

Do the modified RGB TVs accept high amplitude RGB from arcade boards (i.e. 2-5v p-p) or do they still only accept 0.7v p-p?

My set is also a BA-5D that I modded with the old method,before the mux came to be and sync with component works great.

I get the same interference as you,it's really not to bad but it's there enough but I did see on pal sony sets how it's wired for blanking,been meaning to try it to see if that could make a difference.
https://imgur.com/ASQx3a6

If you want help on this forum please provide the model number of the set and exactly what you want to do. Do you want Scart RGB connection?

This is not an easy task and requires some hard work and study on your part. We are not here to do this for you. Please learn the layout of your chassis schematic, take photos of the board.

DO NOT SOLDER WIRES DIRECTLY TO THE NECKBOARD.

You cannot easily mod this TV for analog RGB. It's missing an RGB clamp circuit. Stick with more modern sets 1995+.