Normally yes but not on this set because it's rf only. Instead it goes straight to ground disabling Video mode. There's an S-Video set schematic which shows it being used. It's pin 36 marked "TV/AV"BazookaBen wrote:What was the urpose of the high/low signal before the mod? Seems like it would already switch between TV and video
Hello friend, I have a CRT '21 TV and the Component input has the image flickering, I connected the Y to the Composite AV1 input, the perfect and stable image appears, but black/white, it is possible for me to inject the other 2 cables from the Component in Composite to be colored?nmur wrote:Hey, just stumbled across this thread, and looks like you've done an awesome job here, well done.
I've recently picked up a very similar Australian set:
Model: KV-1415AS
Jungle: CXZ1213BS
IF201: IFD-380A
Chassis: G3E
It's RF only as well, and I have the service manual. The schematics show circuitry for two composite video inputs, however this area on the board in my actual set is totally unpopulated. It looks like you're basically solved this mod to a degree where these schematics won't help you though.
From glancing between your latest diagram and my unit's schematics, adding S-Video might be the same procedure, assuming there's no big difference between ICs. Audio looks different, my schematic involves a switch in that circuit, probably for the 3.5mm jack output.
I can solder/mod stuff, but I have little clue how these circuits work. If you have any thoughts on my set before I go ahead and try stuff, it would be really appreciated.
Oh definitely, I've got floorstanding speakers and headphones with amps for my actual CRT setups - having audio with this mod is just for completeness really. I picked up this set for free and plan to pass it on once it's modded, and I don't know how the next person would choose to use it.BazookaBen wrote:Ugh, don't give youself worse sound though. Grab some external speakers or a headphone amp.
Awesome to see a similar rf only set getting the same treatment.nmur wrote:Oh definitely, I've got floorstanding speakers and headphones with amps for my actual CRT setups - having audio with this mod is just for completeness really. I picked up this set for free and plan to pass it on once it's modded, and I don't know how the next person would choose to use it.BazookaBen wrote:Ugh, don't give youself worse sound though. Grab some external speakers or a headphone amp.
Thanks for the tip, I think you're probably right. There's a headphone output on the front of this set so it will be interesting to see if it works with this mod too.jeffez wrote:Awesome to see a similar rf only set getting the same treatment.nmur wrote:Oh definitely, I've got floorstanding speakers and headphones with amps for my actual CRT setups - having audio with this mod is just for completeness really. I picked up this set for free and plan to pass it on once it's modded, and I don't know how the next person would choose to use it.BazookaBen wrote:Ugh, don't give youself worse sound though. Grab some external speakers or a headphone amp.
With the audio you'll see on my diagram it goes into 'AF IN' on the IF chip. I put it here because it seemed to be the right spot for the signal to go to utilise the TVs existing audio circuitry including it's volume control. No need for external speakers, amp etc. Yours appears have the same option. Might take some trial and error to find the right spot but maybe behind C211.
Yeah that tube would never have looked so good being restricted by RF all this time. Hopefully more people find this and we can save a few more old sets like this.nmur wrote: Thanks for the tip, I think you're probably right. There's a headphone output on the front of this set so it will be interesting to see if it works with this mod too.
I don't have any RCA sockets yet, but I've just performed the video mod, and it looks excellent compared to RF! This is my first input mod, so it's really satisfying seeing it work.
I wired up the audio input today, and found that the C212 capacitor I was originally planning to connect behind was actually just a jump on this board, which reduced the number of options to try, and was a success! I will make the mod more permanent in the near future.jeffez wrote:Yeah that tube would never have looked so good being restricted by RF all this time. Hopefully more people find this and we can save a few more old sets like this.nmur wrote: Thanks for the tip, I think you're probably right. There's a headphone output on the front of this set so it will be interesting to see if it works with this mod too.
I don't have any RCA sockets yet, but I've just performed the video mod, and it looks excellent compared to RF! This is my first input mod, so it's really satisfying seeing it work.
Good stuff!nmur wrote:I wired up the audio input today, and found that the C212 capacitor I was originally planning to connect behind was actually just a jump on this board, which reduced the number of options to try, and was a success! I will make the mod more permanent in the near future.jeffez wrote:Yeah that tube would never have looked so good being restricted by RF all this time. Hopefully more people find this and we can save a few more old sets like this.nmur wrote: Thanks for the tip, I think you're probably right. There's a headphone output on the front of this set so it will be interesting to see if it works with this mod too.
I don't have any RCA sockets yet, but I've just performed the video mod, and it looks excellent compared to RF! This is my first input mod, so it's really satisfying seeing it work.
First of all thank you so much for actually replying, since I managed to inject my own Composchyte signal, the set seems to switch to that as long as pin 19 of the T51496P demodulation IC is off circuit, as soon as I resolder that pin back, the set does not display the signal anymore. I have ordered some spare parts to perform the mod, I will report back if I am successfulBazookaBen wrote:It has a Y and C inputs. So see if you can find any larger models with the same chip that have s-video, and just copy that circuit.
If you can't find another model, then you must have to figure out what sort of termination the chip is looking for. Probably 75ohm like you see on other mods here.
Then, you have to figure out how to get the TV to switch to that input. Maybe it's automatic, maybe it's a service mode tweak, maybe you have to disable RF or composite to get it to work.
Am I understanding correctly that you are managing to get a composite signal to work by sending it to pin 29 (with a coupling capacitor and termination resistor)? Note that pin is for luminance and so if it is working then chroma and sync must be managing to make there way through the circuit to where they need to go. Looks like pin 7 and 16.WOW90 wrote: 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.
I found them on eBay from a local seller in Aus, but it looks like you can buy them from china as a last resort. The only difference is mine also came with a pcb that goes on the back making it easier to install and glue in place.BazookaBen wrote:Where'd you find that s-video connector with the notch on top? All the ones I found at digikey didn't have that so that means I had to modify them so the ps1/2/3 s-video cable would fit.
Thanks, yeah keeping the stock RF mode pretty much doubled the amount neededMarkOZLAD wrote:Awesome mod.
Lots of wires!
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 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.
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.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.
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.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.I'm guessing this is what I could try to do:Spoiler
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?
