Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

The place for all discussion on gaming hardware
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-only TV) SOLVED

Post by KPackratt2k »

Hello. A friend of mine has a 1990 Sony KV-1380R TV that he would like for me to S-Video mod at some point, I have 75 ohm resistors and some capacitors (0.01 and 0.1 uF) that I could use, I've also ordered a panel mount S-Video connector on Digikey. The only problem is that I'm unable to find a service manual for it from a reliable source (preferably for free, but if I have to pay, I'd be willing to since the guy may be offering around $20 if I can mod it). Does anyone have the service manual for this set? If not, I can inspect the chips it has once I get ahold of it and cross-reference a service manual for another model with the same jungle chip (which I'm guessing will be the CXA1013S).

Thanks in advance.
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-only TV) SOLVED

Post by jeffez »

KPackratt2k wrote:Hello. A friend of mine has a 1990 Sony KV-1380R TV that he would like for me to S-Video mod at some point, I have 75 ohm resistors and some capacitors (0.01 and 0.1 uF) that I could use, I've also ordered a panel mount S-Video connector on Digikey. The only problem is that I'm unable to find a service manual for it from a reliable source (preferably for free, but if I have to pay, I'd be willing to since the guy may be offering around $20 if I can mod it). Does anyone have the service manual for this set? If not, I can inspect the chips it has once I get ahold of it and cross-reference a service manual for another model with the same jungle chip (which I'm guessing will be the CXA1013S).

Thanks in advance.
Sounds like your on the right track. I wasn't able to find the exact service manual for mine either, so I went off a different model which seemed practically the same internally. Someone on here mentioned KV-27HFR having a CXA1013S. You should be able to find something close enough if no luck finding your one.
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-only TV) SOLVED

Post by KPackratt2k »

jeffez wrote:Sounds like your on the right track. I wasn't able to find the exact service manual for mine either, so I went off a different model which seemed practically the same internally. Someone on here mentioned KV-27HFR having a CXA1013S. You should be able to find something close enough if no luck finding your one.
I found a service manual for the KV-19TS10/20 which uses the P-3B chassis with the CXA1013S, so if nothing else that could be useful for this model. I've also read that the KV-27TS20/30 also uses the same jungle chip and the higher end model (the KV-27TS30) has an S-Video input. If I can find the service manual for that model, perhaps I can try to replicate its S-Video circuit. If that doesn't work, I have other ideas inspired by the information I've found on this thread.
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

All right, I gave in and bought the Service Manual PDF from the Sam's Photofact website (I typically don't resort to this, but since the guy was willing to pay me to mod his set, I thought it would be justifiable). I took a close look at it and although I was wrong about the jungle chip being a CXA1013AS (it's actually a CX20193), it looks like it still uses Y/C, so it should be capable.

Expand the spoiler to see the diagram.
Spoiler
Image
I'm guessing this is what I could try to do:
Lift the leg of C319 that's routed to C323, solder the leg to a wire on the upper left pin of a DPDT switch and solder the pad to the upper middle pin of the switch. Inject S-Video Chroma (Pin 4 on S-Video connector) to the upper right pin of the switch with a 100 nF capacitor in series and a 75 ohm termination resistor to chassis ground.

Ideas for Luma Injection:
A: Solder the Composite video input to the lower middle pin of the switch. Inject S-Video Luma (Pin 3 on S-Video connector) to the lower right pin of the switch. (Considering there's a 3.58 MHz Luma Trap filter in place, I fear that this might affect the image quality, but it should work nonetheless.)

B: Solder a wire from the base of Q303 to the lower middle pin of the switch. Inject S-Video Luma Pin 3 on S-Video connector) to the lower right pin of the switch with a 100 nF capacitor in series and a 75 ohm termination resistor to chassis ground.

Does this sound right?
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

KPackratt2k wrote:All right, I gave in and bought the Service Manual PDF from the Sam's Photofact website (I typically don't resort to this, but since the guy was willing to pay me to mod his set, I thought it would be justifiable). I took a close look at it and although I was wrong about the jungle chip being a CXA1013AS (it's actually a CX20193), it looks like it still uses Y/C, so it should be capable.

Expand the spoiler to see the diagram.
Spoiler
Image
I'm guessing this is what I could try to do:
Lift the leg of C319 that's routed to C323, solder the leg to a wire on the upper left pin of a DPDT switch and solder the pad to the upper middle pin of the switch. Inject S-Video Chroma (Pin 4 on S-Video connector) to the upper right pin of the switch with a 100 nF capacitor in series and a 75 ohm termination resistor to chassis ground.

Ideas for Luma Injection:
A: Solder the Composite video input to the lower middle pin of the switch. Inject S-Video Luma (Pin 3 on S-Video connector) to the lower right pin of the switch. (Considering there's a 3.58 MHz Luma Trap filter in place, I fear that this might affect the image quality, but it should work nonetheless.)

B: Solder a wire from the base of Q303 to the lower middle pin of the switch. Inject S-Video Luma Pin 3 on S-Video connector) to the lower right pin of the switch with a 100 nF capacitor in series and a 75 ohm termination resistor to chassis ground.

Does this sound right?
It was a little hard to follow without a diagram but excluding the complexity of the DPDT switch and isolating out the stock rf video it sounds like your looking at injecting Chroma into pin 39 and Luma at the base of Q303 both with the 100 nF and the 75R termination? At this point for me it was trial and error. The other consideration is sync. It look likes sync is going to pin 42. Tracing that back shows it coming from between R425 and R320. Some one else might be more help as I have only done this mod on the one set.
User avatar
BazookaBen
Posts: 2077
Joined: Thu Apr 17, 2008 8:09 pm
Location: North Carolina

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BazookaBen »

KPackratt2k, did you find the service manual for KV-27TS30?

The best thing to do is always just copy the intended s-video circuit fro the jungle from a set that already has it. As you saw with my KV-13fm12, it was literally just filling in spots that already existed on the board

The interesting thing about my set though, is that the 27" models used a different jungle chip and board layout, so I only had the 20" and 24" "FV" models to copy
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

BazookaBen wrote:KPackratt2k, did you find the service manual for KV-27TS30?

The best thing to do is always just copy the intended s-video circuit fro the jungle from a set that already has it. As you saw with my KV-13fm12, it was literally just filling in spots that already existed on the board

The interesting thing about my set though, is that the 27" models used a different jungle chip and board layout, so I only had the 20" and 24" "FV" models to copy
Not yet, but since I discovered that the jungle chip for the KV-1380R is actually a CX20193, I don't know if the KV-27TS30 S-Video circuit schematic would be of any use since I've heard that model has a CXA1013AS. I don't know if there's a Sony TV with the CX20193 jungle chip and an S-Video input (If I find the service manual for one, I'll see about copying its circuit and implementing it in this set).

Does the KV-27TS30 service manual exist as a free download on a reputable site (e.g. Internet Archive or Electrotanya)? When doing a quick Google search, I was having a tough time tracking down the service manual for this model, so I wonder if anyone else had better luck than me when it came to finding it.
nmur
Posts: 11
Joined: Thu Aug 22, 2019 12:35 pm

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by nmur »

I don't know how I didn't notice this before - I mustn't have had the TV turned on for very long during the modding/testing stages, but I'm finding that the s-video video signal display fades away to nothing after a couple of minutes. I can still hear audio, as well as the 15kHz whine, and the neck still glows, but no video signal displays, other than the OSD. I've tried different input sources as well. What's also weird is that if I turn off the TV and the source and turn them on again, the video still isn't visible. However if I leave it all turned off for a while, and come back later to try, it will work again for a short while before fading to black again. I didn't observe any obvious overheating of anything inside the TV.

Has anyone witnessed this behaviour with their mod before?
User avatar
BazookaBen
Posts: 2077
Joined: Thu Apr 17, 2008 8:09 pm
Location: North Carolina

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BazookaBen »

My guess would be that you need to check for continuity on one of the signals, like Luma, to make sure it's not bleeding into a different circuit.

Like in my s-video mod, before I removed that jumper that is used to replace the video switching circuit that is present in larger models, I would get an s-video signal that flashed in and out occasionally.

Yours is RF only, right? So you had to replace the Y/C signal coming from the RF input? Maybe the signals are travelling backwards being bled by some capacitor or something?
nmur
Posts: 11
Joined: Thu Aug 22, 2019 12:35 pm

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by nmur »

BazookaBen wrote:My guess would be that you need to check for continuity on one of the signals, like Luma, to make sure it's not bleeding into a different circuit.

Like in my s-video mod, before I removed that jumper that is used to replace the video switching circuit that is present in larger models, I would get an s-video signal that flashed in and out occasionally.

Yours is RF only, right? So you had to replace the Y/C signal coming from the RF input? Maybe the signals are travelling backwards being bled by some capacitor or something?
Yeah it was RF only, I'll have a check, thanks!
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

nmur wrote:
BazookaBen wrote:My guess would be that you need to check for continuity on one of the signals, like Luma, to make sure it's not bleeding into a different circuit.

Like in my s-video mod, before I removed that jumper that is used to replace the video switching circuit that is present in larger models, I would get an s-video signal that flashed in and out occasionally.

Yours is RF only, right? So you had to replace the Y/C signal coming from the RF input? Maybe the signals are travelling backwards being bled by some capacitor or something?
Yeah it was RF only, I'll have a check, thanks!
Yeah it might be where your injecting sync. Might need to find another spot to connect it.
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

Here's my idea on modding the KV-1380R.
Spoiler
Image
Basically, what I'll do is the following:

- Desolder the legs of C319 and C323, wire the legs to the lower left pin of the 3PDT, wire the original C323 pad to the lower middle pin, and S-Video Chroma to the lower right pin with a 100nF capacitor in series and a 75 ohm termination resistor to ground.

- Desolder the legs of C317 and C318, wire their legs to the upper and center left pins of the 3PDT, and wire their pads to the upper and center middle pins (this will disable the Luma trap filter in S-Video mode, which should hopefully clean up the image).

- Run S-Video Luma to the Video input pad of the A-9 header and ground the S-Video grounds to the Ground pad of that header.

- Tie the Y/C/J (IC301) ground to the isolated ground of A-9 through a 100nF film capacitor to reduce the likelihood of AC noise running through the Chroma (not pictured).

Does this sound like a good plan?
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

KPackratt2k wrote:Here's my idea on modding the KV-1380R.
Does this sound like a good plan?
Looks alright though it's probably uncertain until you try it as for how well luma and sync goes. Not sure if you might get interference from the stock rf picture. Someone else may have a better answer.
Ryeno
Posts: 89
Joined: Tue Nov 05, 2019 6:50 am

Re: Sony Trinitron S-Video/Composite Mod (RF-only TV)

Post by Ryeno »

BWF wrote:For example, the data sheet for the CXA1870S (for a KV20S20 set) specifies a "standard input level" of 2Vp-p on the YIN pin. Isnt that supposed to be 0.7V p-p? And when i measure it with a scope, why is it nowhere close to either of these voltages (closer to a 1 Vp-p signal sitting on a 3VDC bias). So here i am with a standard that doesnt match the data sheet which doesnt match the measurement. Really frustrating
Sony designed that Jungle chip to work with an amplifier. The reason for this is because the switch ICs have amplifiers built in. So if you were to bypass all the Sony circuitry, you would want to use a THS7316 (or batter) to amplify the signal before sending into the jungle chip.
firedye
Posts: 1
Joined: Wed Jul 27, 2022 1:04 am

Re: Sony Trinitron S-Video/Composite Mod (RF-only TV) SOLVED

Post by firedye »

WOW90 wrote:Hi there. I got my hands on an old 1995 Toshiba 1400RN set that has only RF input. I wanted to do an RGB mod to it, but since the Jungle IC can only output 8bit RGB signal that is not the case. The set is extremely old and I could not find any schematics for it aside for schematics to a similar model, Toshiba 1400RBT. Looking at the mobo the chips present on it are a Mitsubishi 34300-587SP. That's the OSD chip for which I was not able to find any datasheet but luckily the Toshiba 1400RBT schematics have the pinouts for a similar model, a Mitsubishi 34300-583SP that hopefully works in a similar fashion. The jungle IC is a Toshiba TA8718N for which I found the PDF datasheet. Then a T51496P that seems to be taking care of the demodulation process, sadly I was only able to find a partial datasheet only in the form of a low quality image. For last the audio amplifier is a Philips TDA7052 that takes care of the audio out to the speaker, and thankfully for this one I got the full datasheet PDF in high quality. Here I have posted some pics of the schematics of the chips that the TV has and a schematic of the entire set. I apologize for the low quality image but I was not able to find anything higher quality online. https://imgur.com/a/JeOCBu2
Here instead I posted a link to the PDF datasheets I was able to find online https://drive.google.com/drive/folders/ ... sp=sharing
Anyhow, since I managed to do a Composite mod (basically, desoldered pin 9, and pin 18 of the T51496P demodulation IC, which are respectively Audio Driver Output and Video Output, to bring them off circuit in order to have my have my own Audio Input and Video Input enabled, soldered on pin 29 of the TA8718N IC my Composite input, with a 1uF cap and a 75R parallel resistor to ground.) I was wondering if, based on the schematics, is possible to do a S-video mod for my set. I apologize if I am bothering but since this is my first time attempting such a mod I am afraid I will mess something up, therefore I came here asking for guidance.
Hey, try googling ' Toshiba 218R8E '

It will bring up a service manual with pretty much identical parts to yours, probably better quality images/pinouts for you to work with.

I have this set and it's only rf, would be great if we could attack it together to try and get s-video. I've done a few rgb mods but nothing with rf.

My set is only PAL btw, any ideas on how to convert it to NTSC?
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

I have managed to S-Video mod a 1989 Sony KV-20TS20 TV for a friend who wanted me to mod one of their TVs.

Here are the instructions on how to mod this set:

1. Wire S-Video Luma (Pin 3) to the Composite Video input on the U board and connect the grounds (S-Video Pins 1 and 2) to the Composite Video ground.

2. Remove the jumper (located between R504 and C355) that connects pin 46 of IC301 to pin 4 of CM301 on the chassis (A board).

3. Wire S-Video Chroma (Pin 4) to the jumper via that leads to pin 46 of IC301 and add a 100 nF coupling capacitor to the wire (either on the jumper via or on the S-Video connector pin).

4. Couple the jungle chip ground (IC301 pin 25) to the cold ground (A-3 pin 2 or 3) through a 47-100 nF film capacitor, this will prevent AC noise (humbars) from entering the Chroma signal.

Photo Album: https://imgur.com/a/JngzlnS

EDIT:
By doing the modification in this manner, RF will be in black and white as there's a comb filter chip that separates the tuner video into Y/C and we're cutting the connection on the Chroma line of the comb filter. To mitigate this, you can use a switch to toggle between the RF comb filter Chroma and S-Video. Just use a SPDT switch in the following pinout:

Pin 1: CM301 pin 4
Pin 2: IC301 pin 46
Pin 3: S-Video Chroma (pin 4 on the mini-DIN)
Last edited by KPackratt2k on Sat Apr 08, 2023 3:49 am, edited 1 time in total.
JohnyTheWizKid
Posts: 2
Joined: Sun Aug 28, 2022 11:00 pm

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by JohnyTheWizKid »

jeffez wrote:
KPackratt2k wrote:Here's my idea on modding the KV-1380R.
Does this sound like a good plan?
Looks alright though it's probably uncertain until you try it as for how well luma and sync goes. Not sure if you might get interference from the stock rf picture. Someone else may have a better answer.
Were you able to rgb mod a tv? I have a classy 80s tv I'm looking to rgb and s-video mod. I'm told over on CRT Collective on facebook that it needs to be modded via neck board. I'm looking to hire someone who would like to take on this task.
JohnyTheWizKid
Posts: 2
Joined: Sun Aug 28, 2022 11:00 pm

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by JohnyTheWizKid »

KPackratt2k wrote:I have managed to S-Video mod a 1989 Sony KV-20TS20 TV for a friend who wanted me to mod one of their TVs.

Here are the instructions on how to mod this set:

1. Wire S-Video Luma (Pin 3) to the Composite Video input on the U board and connect the grounds (S-Video Pins 1 and 2) to the Composite Video ground.

2. Remove the jumper (located between R504 and C355) that connects pin 46 of IC301 to pin 4 of CM301 on the chassis (A board).

3. Wire S-Video Chroma (Pin 4) to the jumper via that leads to pin 46 of IC301 and add a 100 nF coupling capacitor to the wire (either on the jumper via or on the S-Video connector pin).

4. Couple the jungle chip ground (IC301 pin 25) to the cold ground (A-3 pin 2 or 3) through a 47-100 nF film capacitor, this will prevent AC noise (humbars) from entering the Chroma signal.

Photo Album: https://imgur.com/a/JngzlnS
Could it be rgb modded?
User avatar
matt
Posts: 567
Joined: Mon May 09, 2005 5:46 am
Location: Honolulu, Hawaii

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by matt »

No, that chassis is too early. Sony didn't start using jungle chips with RGB inputs until a couple of years later. TVs from the '80s are almost never compatible with RGB mods.

You're better off looking for a newer TV, neck board mods are difficult and don't work nearly as well.
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

So I found this Trinitron at a charity shop. Given how hard they are to find in my local area I bought it right there and then. I was hoping to do my first RGB mod but turns out this is another GP-1A chassis with the exact same CXA-1213S jungle as the small RF set in my OP :roll:
It's a KV-2585AS
I guess I'll just s-video mod it. I now have 3 sets with CXA-1213S jungles in them. Seems like I am destined to be the s-video guy :lol:
Image
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

Maybe this is wishful thinking but given this set has composite, it seems like to do svideo all that's needed it so run Luma directly to composite and Chroma to the jungle CIN (pin 1) through a coupling cap with the 75R?
User avatar
BazookaBen
Posts: 2077
Joined: Thu Apr 17, 2008 8:09 pm
Location: North Carolina

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BazookaBen »

jeffez wrote:Maybe this is wishful thinking but given this set has composite, it seems like to do svideo all that's needed it so run Luma directly to composite and Chroma to the jungle CIN (pin 1) through a coupling cap with the 75R?
See if you can find schematics for larger models made in the same time period that had s-video. See if they use the same jungle chip

You might be able to add s-video without a hardware switch.
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

BazookaBen wrote:
jeffez wrote:Maybe this is wishful thinking but given this set has composite, it seems like to do svideo all that's needed it so run Luma directly to composite and Chroma to the jungle CIN (pin 1) through a coupling cap with the 75R?
See if you can find schematics for larger models made in the same time period that had s-video. See if they use the same jungle chip

You might be able to add s-video without a hardware switch.
Here's one I have looked at before.
https://elektrotanya.com/sony_gp-1a_kv- ... nload.html

Image

Edit: just for my reference here is the service manual - https://archive.org/details/manual_KV25 ... 1/mode/2up
User avatar
BazookaBen
Posts: 2077
Joined: Thu Apr 17, 2008 8:09 pm
Location: North Carolina

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BazookaBen »

Yeah, I'd look and see if it has the same jungle chip as yours. See if there is some sort of signal pin between that video switch chip and the jungle that switches to Y/C. And maybe look on DigiKey and see if they sell that video switch chip. It's possible your TV already has that in there.
jeffez
Posts: 100
Joined: Wed Nov 20, 2019 12:46 am
Location: Australia

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by jeffez »

BazookaBen wrote:Yeah, I'd look and see if it has the same jungle chip as yours. See if there is some sort of signal pin between that video switch chip and the jungle that switches to Y/C. And maybe look on DigiKey and see if they sell that video switch chip. It's possible your TV already has that in there.
Yeah I can confirm mine has the same MC14066BCP that's shown in the diagram of the svideo set. Same jungle. There's also allot of unused component spots on the pcb so maybe I can just fill in the missing ones.
User avatar
BazookaBen
Posts: 2077
Joined: Thu Apr 17, 2008 8:09 pm
Location: North Carolina

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BazookaBen »

So this is pretty much the s-video mod thread, right?

I think I found the key to s-video the tiny Toshiba based budget sets like this Durabrand: https://crtdatabase.com/crts/durabrand/durabrand-du1901

There's a large Insignia TV that has s-video and uses the same microcontroller. Y/C on pins 29 and 30. TV model is IS-TV040923. Microcontroller is OEC7091C
https://www.manualslib.com/manual/11120 ... =28#manual

C does the standard termination with 75ohm to ground and 220uf to sink. But Y has some extra stuff in between. Like some voltage division thing going on from the looks of it. It has a resistor in series, and an extra one going to ground. I don't know if this would need to be replicated when s-video modding the other sets.

So I have the 13" version of the Durabrand. Haven't checked the microcontroller but I'm willing to bet it's the same one.
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

BazookaBen wrote: Mon Jul 17, 2023 2:55 am So this is pretty much the s-video mod thread, right?
With this in mind, I thought it would be appropriate to post this here.

Since I've been having trouble RGB modding this set (the jungle chip expects an amplified signal), I've decided to S-Video mod a Sony KV-20VM20 TV/VCR combo.

Luma gets injected to the Composite Video input on the VCR part of the chassis.

On the TV part of the chassis, lift C1502 from the side routed to the Jungle chip and inject Chroma to it with a 0.01uF capacitor in series. You can route the lifted capacitor and your S-Video Chroma through a switch to retain stock functionality.
Image

If you find that Composite, RF, and the VCR output in black and white after performing this mod, try rerouting your Chroma wires, the positioning of the wire is critical for preserving the functionality of the stock inputs. It may also help to use shielded wires for the Chroma circuit.

Photo album:
https://imgur.com/a/LHz4jrF
If you see a content warning when clicking the link, bypass it. Imgur has been having a bug where new albums are flagged NSFW, even when they're not.
Last edited by KPackratt2k on Mon Jul 24, 2023 7:11 am, edited 2 times in total.
BeatriceWright
Posts: 2
Joined: Mon Jul 24, 2023 4:06 am

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by BeatriceWright »

Hy there i can see your post and i have some suggestion

Research Your CRT Model: Identify the specific model of your Trinitron CRT and look for any available documentation or resources related to modifications or enhancements for that particular model.

Find the Jungle IC Pinout: Locate the datasheet or technical documentation for the Jungle IC (the video processor chip) used in your CRT model. This will provide the pinout and functions of the chip.

Locate Luma and Chroma Signals: Identify the pins on the Jungle IC that correspond to the Luma (Y) and Chroma (C) signals. These are the pins you'll need to tap into for the S-Video mod.

Add S-Video Connector: S-Video typically uses a 4-pin mini-DIN connector. You'll need to add this connector to your CRT. Wire the Luma and Chroma signals from the Jungle IC to the appropriate pins on the S-Video connector.

Thanks and regards
BeatriceWright
User avatar
KatKya
Posts: 77
Joined: Wed Mar 25, 2015 7:24 am

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KatKya »

KPackratt2k wrote: Mon May 16, 2022 5:25 am Here's my idea on modding the KV-1380R.
Spoiler
Image
Basically, what I'll do is the following:

- Desolder the legs of C319 and C323, wire the legs to the lower left pin of the 3PDT, wire the original C323 pad to the lower middle pin, and S-Video Chroma to the lower right pin with a 100nF capacitor in series and a 75 ohm termination resistor to ground.

- Desolder the legs of C317 and C318, wire their legs to the upper and center left pins of the 3PDT, and wire their pads to the upper and center middle pins (this will disable the Luma trap filter in S-Video mode, which should hopefully clean up the image).

- Run S-Video Luma to the Video input pad of the A-9 header and ground the S-Video grounds to the Ground pad of that header.

- Tie the Y/C/J (IC301) ground to the isolated ground of A-9 through a 100nF film capacitor to reduce the likelihood of AC noise running through the Chroma (not pictured).

Does this sound like a good plan?
Was curious if you ever got around to giving this a shot.

Also if you happened to still have the schematic/service manual kicking around for the 1380r.
KPackratt2k
Posts: 211
Joined: Sun Apr 04, 2021 11:02 pm
Location: Seattle, WA, USA

Re: Sony Trinitron S-Video/Composite Mod (RF-Only TV) SOLVED

Post by KPackratt2k »

KatKya wrote: Wed Sep 27, 2023 12:46 am Was curious if you ever got around to giving this a shot.

Also if you happened to still have the schematic/service manual kicking around for the 1380r.
My friend ended up selling the TV to someone else, as he changed his mind and decided he didn't want it modded. Therefore, I can't say for certain whether this would work or not.

Here's the service manual:
https://archive.org/details/sony-kv-1380-r-sm

Keep in mind some pages of it weren't scanned correctly by the person who made the PDF, so there may be some portions with missing text.
Post Reply