TV RGB mod thread

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matt
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Re: TV RGB mod thread

Post by matt »

KPackratt2k wrote:Is anyone else having issues getting Sega Saturn CSYNC cables to work on RGB modded consumer TVs? I bought a Sega Saturn RGB SCART CSYNC cable from Retro Access and I'm getting a rolling picture. I've tried replacing the single resistor on the connector board with a 470R just in case that was it and I'm still not getting sync. I don't understand why CSYNC from the Saturn doesn't work because CSYNC from any other console works fine on every TV I've modded.

EDIT: Well shoot, I was doing some testing with a multimeter and discovered that the CSYNC pin on my Saturn is fried. I get nothing when I measure it in AC or DC volts, whereas when I measured the Composite video pin I get 1.2V DC and 2V AC. I was also able to measure the 5V pin and got the expected voltage there. I'm willing to bet the original owner of my Saturn used a cheap SCART cable and somehow fried the CSYNC pin. I'm ordering a Sync-on-Luma cable to replace it and have started a return request for my CSYNC cable.

The resistor I replaced turned out to be for the 5V rail, so I put the old resistor back on there to avoid any suspicions when they receive it back.
FWIW, modded TVs often do choke on TTL level sync. I've never damaged anything with it, but the few times I've accidentally hooked up my Saturn without a resistor on the sync line the TV wouldn't display the image properly. If they left out the 470 ohm resistor it's likely to not to have worked even if your Saturn was OK.

Also another reason to make your own cables.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

matt wrote:FWIW, modded TVs often do choke on TTL level sync. I've never damaged anything with it, but the few times I've accidentally hooked up my Saturn without a resistor on the sync line the TV wouldn't display the image properly. If they left out the 470 ohm resistor it's likely to not to have worked even if your Saturn was OK.

Also another reason to make your own cables.
I checked the cable with a multimeter in resistance mode with one lead on the Sync pin on the SCART connector PCB (before the 220uF capacitor) and the other on the CSYNC pin of the Saturn multi-out plug and got 470 ohms, so it was definitely attenuated, I don't think Retro Access sells SCART CSYNC cables without attenuation, especially considering that would cause problems for anyone who isn't using the OSSC or a TTL capable PVM.

Going by the multimeter voltage readings from my further testings I believe the issue was that the pin on the console was fried in some way (maybe a bad capacitor or resistor coming from the pin). I can't do anything about it ATM because the only schematics I could find are for the PAL Sega Saturn which doesn't have CSYNC. I'll have my friend bring his Saturn over to my place and I'll test the cable on it to see if I'm right.
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matt
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Re: TV RGB mod thread

Post by matt »

I guess you could jump Luma to the Csync pin on the console.
Greenman
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Re: TV RGB mod thread

Post by Greenman »

Hi all. I'm trying to identify the blanking terminal on this board. Not as easy as I would have thought.

The OSD traces out from CTS863 to TB1231N:

https://s3p.manualzz.com/store/data/054 ... 17&p=86400

Any ideas what the go is here?
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Greenman wrote:Hi all. I'm trying to identify the blanking terminal on this board. Not as easy as I would have thought.

The OSD traces out from CTS863 to TB1231N:

https://s3p.manualzz.com/store/data/054 ... 17&p=86400

Any ideas what the go is here?

Check out my post about a TV with near identical chassis.

viewtopic.php?f=6&t=60158
___________________________________________________
MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

Sharp 19L-M100BS done. For the most part a by-the-book RGB mux. Only deviation is using 100-ohm grounds for the RGB inputs since the image is too dark when using 75-ohm. No need to go into detail as this site covers it quite well:

https://crtdatabase.com/crts/sharp/sharp-13k-m100b

Picture on this this is outstanding and the geometry is perfect. Only adjustment I made was to move the image to the right slightly via the service menu.

Image
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matt
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Re: TV RGB mod thread

Post by matt »

Osirus wrote:Sharp 19L-M100BS done. For the most part a by-the-book RGB mux. Only deviation is using 100-ohm grounds for the RGB inputs since the image is too dark when using 75-ohm. No need to go into detail as this site covers it quite well:

https://crtdatabase.com/crts/sharp/sharp-13k-m100b
Nice to see that page getting some use. Did you notice any differences between your 19" model and the 13" version?

These Sharps are real basic entry level TVs but they do have a very clean picture once modded.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

matt wrote: Nice to see that page getting some use. Did you notice any differences between your 19" model and the 13" version?
No, everything described there looked the same. Component numbers, chassis layout, all the same. My mod didn't utilize the unused headers on the chassis but that's just personal preference.
appletesticle
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Re: TV RGB mod thread

Post by appletesticle »

Hello, I've been very keen on RGB modding a CRT TV for a few months now but never got around buying or picking up one for free until about a week ago where I saw a CRT thrown by the trash. I took it home. For the past 2-3 days I've been obsessing on trying to understand everything I could, and so far I'm confident on my understanding with the switching method but I want to try the mux method as my first try for a challenge. I essentially need someone to grade my homework, if it's correct or not. For the blanking line input, I'm just taking into account for SCART as I do not know if I will go SCART, RCA/RCA, or even both.
Sanyo DS24205 Factory PCB
Mux mod proposition
Few questions also...
1) the resistor for the R line is a carbon one, whereas for lines G and B are surface mount, are these interchangeable? Can I use a SMD resistor to replace a carbon one? Vice versa?
Spoiler
2) For the 2nd testing point on the Blue line named "B_TP_2", its identification was a guess based off continuity rather than following the trace from the bottom side of the B resistor (since I can't follow it). I see R and G have 2 testing points each, which leads me to assume that B would have 2 as well. I tested for continuity from B_TP_2 to the south side of the B resistor, there is. B_TP_2 to Pin 14 on the Jungle Chip, there is. Testing for continuity from the north side of the B resistor, there is none. Is it safe to assume this is the 2nd testing point for the B line? [I've answered this with a schematic that I found of my TV which shows all the lines.]
Spoiler
Edit 1: [09/21/2022 21:27EDT] Oh hell I totally missed the 100nF capacitor near the Jungle Chip RGB input, will have to update this later.
Edit 2: [09/21/2022 21:48EDT up to date] I'm assuming the 100nF caps are just for the new incoming RGB signals, and not for the original OSD + New RGB Siginals since the original OSD didn't originally require 100nF, meaning I can put these 100nF caps right after the factory rated resistors on the new incoming RGB lines.
Last edited by appletesticle on Thu Sep 22, 2022 6:54 pm, edited 2 times in total.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

appletesticle wrote:Hello, I've been very keen on RGB modding a CRT TV for a few months now but never got around buying or picking up one for free until about a week ago where I saw a CRT thrown by the trash. I took it home. For the past 2-3 days I've been obsessing on trying to understand everything I could, and so far I'm confident on my understanding with the switching method but I want to try the mux method as my first try for a challenge. I essentially need someone to grade my homework, if it's correct or not. For the blanking line input, I'm just taking into account for SCART as I do not know if I will go SCART, RCA/RCA, or even both.
Sanyo DS24205 Factory PCB
Mux mod proposition
Few questions also...
1) the resistor for the R line is a carbon one, whereas for lines G and B are surface mount, are these interchangeable? Can I use a SMD resistor to replace a carbon one? Vice versa?
2) For the 2nd testing point on the Blue line named "B_TP_2", its identification was a guess based off continuity rather than following the trace from the bottom side of the B resistor (since I can't follow it). I see R and G have 2 testing points each, which leads me to assume that B would have 2 as well. I tested for continuity from B_TP_2 to the south side of the B resistor, there is. B_TP_2 to Pin 14 on the Jungle Chip, there is. Testing for continuity from the north side of the B resistor, there is none. Is it safe to assume this is the 2nd testing point for the B line?
Spoiler
Edit 1: [09/21/2022 21:27EDT] Oh hell I totally missed the 100nF capacitor near the Jungle Chip RGB input, will have to update this later.
Edit 2: [09/21/2022 21:48EDT up to date] I'm assuming the 100nF caps are just for the new incoming RGB signals, and not for the original OSD + New RGB Siginals since the original OSD didn't originally require 100nF, meaning I can put these 100nF caps right after the factory rated resistors on the new incoming RGB lines.
Mod thread for a similar model here, see if it helps: viewtopic.php?f=6&t=66379
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

I've successfully RGB (and Composite) modded an RCA S13801CL SecureView Prison TV for a friend who was lucky enough to obtain it. Another member has gone through the trouble of figuring out the proper way to mod this particular set, their helpful posts coupled with my previous experience from modding a TV with a near-identical chassis ensured that this would be a one-shot success.

https://imgur.com/a/wpOgwCV

Image
Image

The jungle chip used in this set expects a 1.0vp-p signal on the RGB inputs, so 180 ohm termination had to be used as explained by the other person who modded one of these. viewtopic.php?p=1479889#p1479889
abispac
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Re: TV RGB mod thread

Post by abispac »

A friend of mine has a 19 inch rca RCA F19421 that looks to be a great candidate for rgb mod, and i really could use it for my next project, i still have not opened it yet, but i hope ill get on that this weekend.
Anyway, so from the schematich, looks like 14-17 are my main contacts, and based on Markozlad guide i should use 470 resistors right? I apreciate any help as i have screw up many times, but also saved alot from th efine guys here, specially Markozlad. Anyway thanks for watching.
Image
https://pdfhost.io/v/dgkfizvHx_Section11doc
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Re: TV RGB mod thread

Post by KPackratt2k »

This looks to be a TX808 chassis which uses a Toshiba TA1268N jungle chip configured for 1.0vp-p level RGB, the 470 + 75 ohm setup will not work as the Micon RGB signal would overdrive the tube and your external RGB would be too dim. Use 680 ohm resistors as your inline resistors and 180 ohm resistors as your grounding resistors. See the diagram in the Imgur link on my post above yours for my modding procedure for this chassis.
abispac
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Re: TV RGB mod thread

Post by abispac »

KPackratt2k wrote:This looks to be a TX808 chassis which uses a Toshiba TA1268N jungle chip configured for 1.0vp-p level RGB, the 470 + 75 ohm setup will not work as the Micon RGB signal would overdrive the tube and your external RGB would be too dim. Use 680 ohm resistors as your inline resistors and 180 ohm resistors as your grounding resistors. See the diagram in the Imgur link on my post above yours for my modding procedure for this chassis.
O wow,looks just in time for me and super easy, thanks.
Seth562
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Re: TV RGB mod thread

Post by Seth562 »

Whilst I'm documenting Sony mods, here are the design diagrams I made for John M on the CRT Collective to mod his Sony KV-27S42 TV with BA-4D chassis using the OSD Mux method. He implemented it with great success.

This was done when I was still using diodes.

The basic process is:
- remove the existing inline throughole resistors R025, R026 and R027
- replace each of them with a 2K4R and a 1n4148 diode
- remove surface mount resistors R086, R087 and R088
- On the external RGB lines use 75R terminations to ground and then 430R inline
- Connect the external RGB lines to the leg of the diodes closest to the jungle
- Connect 5V to switch the switch to 1KR and solder after the existing R028 inline resistor on the blanking circuit

The theory behind the mod exactly the same as for the BA-5D, just a bit easier to implement because of the throughole resistors R025, R026 and R027.

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If you wanted to drop the diodes you could use 330R on the External RGB lines.

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Or even use 1000R/100R..

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https://www.svideo.com/bnc-sv-fm.html?f ... a2YJAO1zfo

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Some other things of note from this mod:

- John was originally using a purchased sync cleaner and couldn't get the TV to sync, he removed this from the setup and it worked
- John purchased an RCA to S-Video adapter and fed sync into S-Video. He said this fixed the image shifting you normally see.
Mark will this work for the KV-20S42? Most of the components are located in the same location, except one of the resistors I saw that needs to be removed.
abispac
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Re: TV RGB mod thread

Post by abispac »

A little off topic, but remains in this category. I was wondering, (and i just wonder as i dont have any knowldge on electronics), i was wondering if it could e posible to replace width caps with somethingthat could help rgb moded tvs to adjust horizontal and vertical width, just as with arcade monitors.
Since we allready tapping them, maybe we can go even further. Maybe is posible maybe is not.
Thanks for reading.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

Seth562 wrote:Mark will this work for the KV-20S42? Most of the components are located in the same location, except one of the resistors I saw that needs to be removed.
After taking a look at the service manual, the resistors you want to remove are R087, R088, and R089. Otherwise it should be similar to the mod you've quoted.
Seth562
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Re: TV RGB mod thread

Post by Seth562 »

KPackratt2k wrote:
Seth562 wrote:Mark will this work for the KV-20S42? Most of the components are located in the same location, except one of the resistors I saw that needs to be removed.
After taking a look at the service manual, the resistors you want to remove are R087, R088, and R089. Otherwise it should be similar to the mod you've quoted.
KPackratt2k/All,

I modded my KV-20S42 with the KV-27S42 guide and I'm left with a blank screen and statics. It looks like the blanking has been activated which is made obvious by the channel screen being turned black. OSD is working, but no RGB/SYNC signals are coming through.

The TV is being hooked up to my Computer which is running CRTEMUDRIVER with the H/V sync being tied together by each getting a 1k ohm resistor and twist-tied together at the end. I'm taking ground from one of the RCA jacks as shown in the picture. For Sync i'm using a spliced composite cable, the same one I used for my RGB modded KV-32FS10, this makes me certain the VGA connection and sync are wired up properly.

I dropped pictures on Imgur in the link below:

https://imgur.com/a/CNu3jas
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

Seth562 wrote:I modded my KV-20S42 with the KV-27S42 guide and I'm left with a blank screen and statics. It looks like the blanking has been activated which is made obvious by the channel screen being turned black. OSD is working, but no RGB/SYNC signals are coming through.
Try removing the 1K ohm resistor you've added on the blanking circuit from the 5V line. From what I remember in an older post someone had a similar issue with the 13-inch version of your TV when they followed Mark's diagram verbatim, so his suggestion was to not have a 1K ohm resistor on the 5V line for blanking and it worked.
MarkOZLAD wrote:Apparently there is an issue with my blanking circuit in the document.

People are having more success by just wiring 5V direct to the diode without the 1K resistor.
Greenman
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Re: TV RGB mod thread

Post by Greenman »

Here is another one to add to the list. A TEAC CT-M342H. It is quite a common 13" 34cm TV around the world.

Image

Image

https://youtu.be/XjWcdB9sFms

Now if anyone could help me adjust the vertical/horizontal it would be very much appreciated. Or if anyone knows what remote goes with this TV, I will purchase one and use the service menu if possible.
abispac
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Re: TV RGB mod thread

Post by abispac »

Greenman wrote:Here is another one to add to the list. A TEAC CT-M342H. It is quite a common 13" 34cm TV around the world.

Image

Image

https://youtu.be/XjWcdB9sFms

Now if anyone could help me adjust the vertical/horizontal it would be very much appreciated. Or if anyone knows what remote goes with this TV, I will purchase one and use the service menu if possible.
I just use a regular universal remote, but the ones that are old, like an rca universal remote, even the old dish remotes would work, ans use the secuense that is on the service manual, works everytime.
Greenman
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Re: TV RGB mod thread

Post by Greenman »

abispac wrote:
Greenman wrote:Here is another one to add to the list. A TEAC CT-M342H. It is quite a common 13" 34cm TV around the world.

Image

Image

https://youtu.be/XjWcdB9sFms

Now if anyone could help me adjust the vertical/horizontal it would be very much appreciated. Or if anyone knows what remote goes with this TV, I will purchase one and use the service menu if possible.
I just use a regular universal remote, but the ones that are old, like an rca universal remote, even the old dish remotes would work, ans use the secuense that is on the service manual, works everytime.
Thank you!! I've just purchased a universal remote and got it to function on all the main menus. However there is no vertical or horizontal adjustment. Is there a particular way to access the service menu on this TV?
abispac
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Re: TV RGB mod thread

Post by abispac »

Greenman wrote:
abispac wrote:
Greenman wrote:Here is another one to add to the list. A TEAC CT-M342H. It is quite a common 13" 34cm TV around the world.

Image

Image

https://youtu.be/XjWcdB9sFms

Now if anyone could help me adjust the vertical/horizontal it would be very much appreciated. Or if anyone knows what remote goes with this TV, I will purchase one and use the service menu if possible.
I just use a regular universal remote, but the ones that are old, like an rca universal remote, even the old dish remotes would work, ans use the secuense that is on the service manual, works everytime.
Thank you!! I've just purchased a universal remote and got it to function on all the main menus. However there is no vertical or horizontal adjustment. Is there a particular way to access the service menu on this TV?
I couldnt find the instructions for your particular set, but what i did with mine, wich also i couldnt find, i found a similar set or even the same brand, use the codes and it work just fine, so by doing the same as with me. here are some instructions, hope it works for you.

Enter service modePress and hold the VOLUME DOWN key tightly on the unit until minimum level and don't release theVOLUMN DOWN key, then press the DISPLAY key on the remote handset three times."D" letter on the screen indicated that the factory mode was entered. Now you can use the shortcut keyto access the factory menu. All change in factory data will save in EEPROM automaticallyNote:1. You can disable the D-Mode key (on factory remote handset) by change "BIT-0" of "MODE2" to"0". If the D-Mode key was disabled, you can't enter D-Mode by the D-mode key on the factoryremote (but you can still enter service mode). It is suggested to disable the D-Mode key before theset leave the factory.2. On the factory remote handset, you can find the "BUS OFF" key. It can cut off the Ithe CPU to other IC. This is only useful when automatic adjustment of white balance.3. All system data in menu of "key 7" must keep unchanged when servicing. Otherwise, the set may notwork properl
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

I'm attempting to RGB mod a Samsung SAM-21M CCTV monitor. It uses a TDA8842 jungle chip, oddly enough its OSD isn't being output to the RGB input of the jungle chip, as its pins are tied to ground via 22nF capacitors. Here's what I did:

- Lifted the 3 capacitors (C205, C206, and C208) out of ground and injected 75 ohm terminated RGB to the legs I've pulled.
- Lifted the leg of the RGB blanking resistor that comes after the jungle chip and connected a 3 AA battery holder to it for testing. The negative end of the battery holder is connected to a nearby ground.
- Tested blanking with 1 battery (1.5V), 2 batteries (3V), and 3 batteries (4.5V).

After doing these things to it, I'm not getting any picture regardless of the blanking voltage and whether the battery holder is on or off. The OSD shows up, but nothing beyond that.

I haven't been able to find the service manual, so I just relied on the datasheet for the jungle chip to determine the pins to inject into.

If anyone has any ideas on things I can try to get this working, I'd appreciate it.
Seth562
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Re: TV RGB mod thread

Post by Seth562 »

KPackratt2k wrote:
Seth562 wrote:I modded my KV-20S42 with the KV-27S42 guide and I'm left with a blank screen and statics. It looks like the blanking has been activated which is made obvious by the channel screen being turned black. OSD is working, but no RGB/SYNC signals are coming through.
Try removing the 1K ohm resistor you've added on the blanking circuit from the 5V line. From what I remember in an older post someone had a similar issue with the 13-inch version of your TV when they followed Mark's diagram verbatim, so his suggestion was to not have a 1K ohm resistor on the 5V line for blanking and it worked.
MarkOZLAD wrote:Apparently there is an issue with my blanking circuit in the document.

People are having more success by just wiring 5V direct to the diode without the 1K resistor.
Thanks KPackratt2K, I was able to get it working. Picture is very crisp and colorful. I can't imagine how a PVM looks it if this is already good.
abispac
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Re: TV RGB mod thread

Post by abispac »

KPackratt2k wrote:I've successfully RGB (and Composite) modded an RCA S13801CL SecureView Prison TV for a friend who was lucky enough to obtain it. Another member has gone through the trouble of figuring out the proper way to mod this particular set, their helpful posts coupled with my previous experience from modding a TV with a near-identical chassis ensured that this would be a one-shot success.

https://imgur.com/a/wpOgwCV

Image
Image

The jungle chip used in this set expects a 1.0vp-p signal on the RGB inputs, so 180 ohm termination had to be used as explained by the other person who modded one of these. viewtopic.php?p=1479889#p1479889
Hey Kpackratt2k, i was wondering, based on your pictures, seems that you injected the imagge directly into the 3.3k resistors without removing them. then added the 820 or 680 resistors (ima do 680 as i wont be usig diodes) and at the end on the jacks, you added the 180 resistors, one end to the postive jack and the other end to the ground. Am i right? is this what it worked for you? Thanks for your time.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

abispac wrote:Hey Kpackratt2k, i was wondering, based on your pictures, seems that you injected the imagge directly into the 3.3k resistors without removing them. then added the 820 or 680 resistors (ima do 680 as i wont be usig diodes) and at the end on the jacks, you added the 180 resistors, one end to the postive jack and the other end to the ground. Am i right? is this what it worked for you? Thanks for your time.
That is correct. The 680 ohm resistors are our OSD mux resistors, and the 180 ohm resistors are our 1.0vp-p RGB termination resistors from signal to ground. This goes hand in hand with the OSD muxing diagram that Mark posted numerous times. The reason we're using 180 ohm rather than the usual 75 ohm for this chassis is due to the expected levels for the jungle chip.
abispac
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Re: TV RGB mod thread

Post by abispac »

KPackratt2k wrote:
abispac wrote:Hey Kpackratt2k, i was wondering, based on your pictures, seems that you injected the imagge directly into the 3.3k resistors without removing them. then added the 820 or 680 resistors (ima do 680 as i wont be usig diodes) and at the end on the jacks, you added the 180 resistors, one end to the postive jack and the other end to the ground. Am i right? is this what it worked for you? Thanks for your time.
That is correct. The 680 ohm resistors are our OSD mux resistors, and the 180 ohm resistors are our 1.0vp-p RGB termination resistors from signal to ground. This goes hand in hand with the OSD muxing diagram that Mark posted numerous times. The reason we're using 180 ohm rather than the usual 75 ohm for this chassis is due to the expected levels for the jungle chip.
Thanks ill post results tomorrow.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

abispac wrote:Thanks ill post results tomorrow.
I forgot to mention, make sure you remove the surface mount factory OSD grounding resistors (RR535, RR536, and RR537) first, as your 680 ohm inline resistors will be replacing them. If you don't, then the OSD will be attenuated twice and this can cause some issues.
abispac
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Re: TV RGB mod thread

Post by abispac »

KPackratt2k wrote:
abispac wrote:Thanks ill post results tomorrow.
I forgot to mention, make sure you remove the surface mount factory OSD grounding resistors (RR535, RR536, and RR537) first, as your 680 ohm inline resistors will be replacing them. If you don't, then the OSD will be attenuated twice and this can cause some issues.
DANG i had high hopes for this set, but:
As per your instructions, i removed the rr535-37 resistors, added the 680 resistors, plus the 180 termination to, and the 75 resistor to the sync, removed the componets in CVBS as in the picture. Wraped everything up, conected my tv to the electricity, andddddddddddddd is dead hehehehe
I almos never mess to much with this things, as they are dirty cheap locally, but this time ill give it a go, if you or anyone else, had any idea where should i beging.
I dont hear any click at all, nothing, totally dead. So ill take ides. Thanks for reading.

EDIT: So turns out it was a cold solder, took care of that and the tv turns on just fine, also this set does not make any noise once it turns on like most crts do. So i get image but menu its 100% unreadeble. My guess?
When i bought the resistors and came home, i tested them out with my multimeter, and i got nothing. So i called the store to let them know they were selling bad resistors, and they told me they tested a couple and they came out good, so i thought my multimeter was going bad. so i did the job anyway, and this is the result, so i think those resistors where indeed bad. tried my multimeter on many resistors, and they read just fine, so i can confirm the multimeter works just fine. So tomorrow ill buy new resistors somehwre else and try againg. Im pretty sure it will work just fine this time. Judging by the look on the colors of the tv, it should look fantastic. So fingers crossed.
Image
image super resolution online
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