JVC TM-H and DT-V thread

[croy]

For the past few months my dt-v1710cg has been having intermittent signal bus errors and now its finally died with both the a and b inputs flashing indicating a deflection bus error and signal bus error. Does anyone have any ideas on repairing the signal pwb or a lead on where to obtain a replacement?

[famiac]

I have a parts DT-V1710CG with the signal pwb. It arrived with tube damage so i'm parting it out. Let me know if you're interested

[croy]

That would be great thanks. I'll send a pm and we can sort out the details

[sporty]

Anyone with experience of using a raspberry pi with a DT-V1710CG? It has a JVC IF-C01COMG RGB card and I've tried different solutions but only getting a black screen even if it recognizes the signal on some level, but then it's just a 480i black screen.
I've tried both RGB-Pi with scart and Retropie with HDMI conversion (both work on another crt) but here I get nothing
Some seem to hint at it being a sync issue that could be fixed with something like an Extron RGB 203 Rxi but then I need to convert the signal to VGA first, it's all just a big headache

[fernan1234]

HDMI conversion (both work on another crt)

Is this HDMI to component (YPbPr)?

I've found many of these converters, like the popular Portta, don't work very well with these monitors. You may have better luck using HDMI to VGA converters. And you don't need an Extron RGB interface (especially a 203 Rxi which can be very expensive nowadays), since unlike other pro monitors that need sync combined into RGBS, these monitors work with RGBHV inputs (sometimes even better than RGBS).

A quirk that I realized a while ago is that sometimes the monitor will not sync to an RGBS input when it has a line connected to the V sync on the RGB card, though this is rare and I only encountered it when using RGBS + certain MiSTer cores. Mentioning in case it may also affect RGBS from some Raspberri Pi hats.

[sporty]

HDMI conversion (both work on another crt)

Is this HDMI to component (YPbPr)?

It's HDMI->scart and scart->RGB, this one specifically https://www.retrogamingcables.co.uk/aud ... verter-bnc
That is with the Retropie OS. The RGB-Pi OS has it's own scart connected to the rpi GPIO pins so it outputs a different signal but I get the same result as before, just black

The RGB card in the tv is this one https://www.retroupgrades.co.uk/product ... -monitors/

This works perfectly on the other crt (Ikegami) but gets me nowhere on the JVC. I'm leaning towards raspberry pi being the problem here and that a normal console or a Mister would work.

[zer0dahero]

I have a JVC DT-V1710CGE that makes this clicky sound at pretty regular intervals (maybe once every couple mins) when the tube is off but the PSU is still getting power. Any clues what it might be? It sounds a bit like a relay, but a lot fainter
It only happens when the screen is off

[fernan1234]

I have a JVC DT-V1710CGE that makes this clicky sound at pretty regular intervals (maybe once every couple mins) when the tube is off but the PSU is still getting power. Any clues what it might be? It sounds a bit like a relay, but a lot fainter

Do you have anything plugged in to the inputs that may be sending a sync signal to the monitor?

[zer0dahero]

I have a JVC DT-V1710CGE that makes this clicky sound at pretty regular intervals (maybe once every couple mins) when the tube is off but the PSU is still getting power. Any clues what it might be? It sounds a bit like a relay, but a lot fainter

Do you have anything plugged in to the inputs that may be sending a sync signal to the monitor?

It still happens with no input cards installed.
Somebody suggest it might be the degauss circuit charging up before turning on the screen, when it tops up it activates the relay and that's the click I hear. It's as good a guess as any because I have no clue. It only happens when the screen is off and monitor works fine so I'm not too worried, I would like to know nonetheless.

I also removed the top cover and looked inside in complete darkness for any sparks but I see nothing

[carlocgc]

i have to recap my 1900, I search a part list pdf for 1900 but not find it :/
anyone already made a capkit list or partial of some board ? (maybe from a 1910)

I don't know if some of the components are also the same on the 1710, if so, if someone has a list I'm also interested

I have a complete parts list for the 1900 and the 1910 suppliment DM me

I also have issues with breathing on bright screens on a 1910.
I've tried to fix the same issue on a couple of consumer grade portables by recapping with no success so im hesitant to dive into the 1910.

@lewolfeur have you managed to fix your issue? has anyone managed to fix breathing issues on these monitors before?
Some people say its the caps some say its the flyback but I cannot find anyone who has actually fixed or even reduced the issue via repair.

[zer0dahero]

I have a JVC DT-V1710CGE that makes this clicky sound at pretty regular intervals (maybe once every couple mins) when the tube is off but the PSU is still getting power. Any clues what it might be? It sounds a bit like a relay, but a lot fainter

Do you have anything plugged in to the inputs that may be sending a sync signal to the monitor?

It still happens with no input cards installed.
Somebody suggest it might be the degauss circuit charging up before turning on the screen, when it tops up it activates the relay and that's the click I hear. It's as good a guess as any because I have no clue. It only happens when the screen is off and monitor works fine so I'm not too worried, I would like to know nonetheless.

I also removed the top cover and looked inside in complete darkness for any sparks but I see nothing

Nevermind, I figured out the culprit. I still have no idea why, but it only happens when it's plugged in this power strip I got, when it's plugged directly into the wall socket or the ups the clicking is gone.
It's weird because apart from that tiny click the monitor works fine when plugged in the power strip. Maybe some power saving feature that doesn't gel well with the monitor when it's sipping power in standby idk

[serbusfish]

wanted to share this simple circuit you can use to dramatically increase the sync compatiblity of your DT-V monitor.
Building the circuit into your RGB card will allow you to use 75 ohm composite video or c-sync as your sync signal without the need of an extron box to shift the voltage levels to TTL.



it's just an LM1881 with level-shifting.
Here's a photo of it installed:



after modding your card, your DT-V will still be compatible with everything you have hooked up already but the need for an external sync processor will be eliminated in most cases.

I have an issue with certain consoles such as NES where the top of the screen is distorted, will this mod fix this issue? Will it also allow devices such as the RGB-Pi to work?
Do I just need to acquire the parts and assemble or does the chip need to be flashed with software?

[carlocgc]

I have compiled the cap info for the JVC DT-V 1910 CG from the parts list and have added some data about the function of the caps on the main board.
I will be using it for a future recap on my set but ill share it here in case its useful to others
https://docs.google.com/spreadsheets/d/ ... sp=sharing

[zer0dahero]

I have compiled the cap info for the JVC DT-V 1910 CG from the parts list and have added some data about the function of the caps on the main board.
I will be using it for a future recap on my set but ill share it here in case its useful to others
https://docs.google.com/spreadsheets/d/ ... sp=sharing

I have a DT-V 1710CG and I'm considering a recap in the future. Do you know if these sets have any electrolytics with specific requirements in terms of ripple current? The service manual doesn't mention it (only the ESR tolerance). I usually go with the highest ripple current rating I can find, but I've never recapped a monitor so idk if they used anything special

[carlocgc]

I have compiled the cap info for the JVC DT-V 1910 CG from the parts list and have added some data about the function of the caps on the main board.
I will be using it for a future recap on my set but ill share it here in case its useful to others
https://docs.google.com/spreadsheets/d/ ... sp=sharing

I have a DT-V 1710CG and I'm considering a recap in the future. Do you know if these sets have any electrolytics with specific requirements in terms of ripple current? The service manual doesn't mention it (only the ESR tolerance). I usually go with the highest ripple current rating I can find, but I've never recapped a monitor so idk if they used anything special

I'm afraid I don't know about ripple current on these, afaik ripple current rating is just another measure of life expectancy and if unsure just get the highest you can within your budget.
The service manual and parts list I have for 1900 don't mention ESR.

I was experiencing increased blooming and rarely a shrinking raster that would quickly correct itself also some x-ray warnings on start-up. I suspected problems with the high voltage regulation and was considering a recap.
Pending some more testing I appear to have fixed all these issues simply by reseating the HV control module (small daughter board near the fly back) and reseating a the socketed chips on the signal board.
I'm not sure which of these worked for my issues but its worth a shot if anyone is having these issues with the 1900/1910 maybe even the 1710 etc.

[zer0dahero]

I have compiled the cap info for the JVC DT-V 1910 CG from the parts list and have added some data about the function of the caps on the main board.
I will be using it for a future recap on my set but ill share it here in case its useful to others
https://docs.google.com/spreadsheets/d/ ... sp=sharing

I have a DT-V 1710CG and I'm considering a recap in the future. Do you know if these sets have any electrolytics with specific requirements in terms of ripple current? The service manual doesn't mention it (only the ESR tolerance). I usually go with the highest ripple current rating I can find, but I've never recapped a monitor so idk if they used anything special

I'm afraid I don't know about ripple current on these, afaik ripple current rating is just another measure of life expectancy and if unsure just get the highest you can within your budget.
The service manual and parts list I have for 1900 don't mention ESR.

I was experiencing increased blooming and rarely a shrinking raster that would quickly correct itself also some x-ray warnings on start-up. I suspected problems with the high voltage regulation and was considering a recap.
Pending some more testing I appear to have fixed all these issues simply by reseating the HV control module (small daughter board near the fly back) and reseating a the socketed chips on the signal board.
I'm not sure which of these worked for my issues but its worth a shot if anyone is having these issues with the 1900/1910 maybe even the 1710 etc.

On the parts list I have for my DT-V there's a letter next to the capacitance and voltage values. I assumed it referred to the markings for ESR tolerance. J=5% K=10% M=20%

[carlocgc]

Yes you're correct the letter signifies the ESR value. I had missed that legend at the top of the parts list.

[GillianSeed]

Hi, I'm looking for some help

I bought a DT-V1710CG monitor last year, I read quite a bit about sync issues at the time but went ahead anyway. I've had some minor issues wIth a Japanese Saturn via csync or luma scart cable I get a 'micro juddering' effect or with Neo Geo I get flagging at the top of the screen. But connecting Japanese Super Famicom or Megadrive directly via RGB scart always worked fine.

So i'm trying to add a gscartw and an Extron 201 rxi to mysetup so I can have multiple consoles connected and make use of the H/V position and sync processing features of the Extron. I'm testing with a Japanese Super Famicom into a gscartw via RGB Scart, outputting from the gscart via VGA to the extron 201 and then using a BNC to male scart connector (RGBS) to connect to my DT-V monitor (I'm also using a phoenix connector with phono outputs for sound). I'm using a third party scart input card from retro upgrades with optional phono inputs in my monitor.

Here is how the Extron is wired up:



I can see the extron is getting a signal ok.



With DDSP and SOG set to ON and my DT-V set to EXT Sync via the menu. I get the 'Out of range' message (If I try this on my JCV TM-H150CG I get a rolling screen). I can't work out why this would be as the DT-V does accept direct scart input (RGBS) no problem.



With the DDSP and SOG dip switches OFF (so no sync processing and RGsB) I get a nice clean image but no sound (I can adjust the brightness and scanline sharpness but not H and V position)



if i set DDSP to ON and SOG to OFF I get a bright green image with flagging in the top corner!



At no point can i get any sound at all, so i'm quite confused - unless the internal dip switches on the Extron need to be reset.. i'm not sure what to do next. I'd appreciate any help as i'm pushing the limits of my knowledge and it's possible i'm doing something stupid

Thanks.

[fernan1234]

At no point can i get any sound at all, so i'm quite confused - unless the internal dip switches on the Extron need to be reset.. i'm not sure what to do next. I'd appreciate any help as i'm pushing the limits of my knowledge and it's possible i'm doing something stupid

Just route your audio separately. I hope you're not trying to feed audio to the dinky mono speaker on the monitor. Your games' audio deserve better than that!

[Pasky]

Has anyone found a solution for the screen curl also known as 'flagging' on the top of the screen when using some old consoles and arcade PCBs? Attached isn't my picture but it's the problem I have with CPS1/CPS2/PGM and numerous other boards when using this monitor. I was told running it through an extron would fix it with the serrated dip on but this does not solve my issue. At least not with with an Extron SC210 or an Extron 203.

[fernan1234]

Has anyone found a solution for the screen curl also known as 'flagging' on the top of the screen when using some old consoles and arcade PCBs? Attached isn't my picture but it's the problem I have with CPS1/CPS2/PGM and numerous other boards when using this monitor. I was told running it through an extron would fix it with the serrated dip on but this does not solve my issue. At least not with with an Extron SC210 or an Extron 203.

If the serration switch doesn't work you'd have to do something a bit more radical like running the arcade boards through some converter/transcoder. With composite/s-video signals that have top flagging like this on these DT-V monitors my solution is to run them through a Retrotink 2X Pro or Multiformat in passthrough mode, and then converting the HDMI output to RGBHV with a DAC. You could probably do the same with an OSSC (or OSSC Pro) set to passthrough mode as well (the OSSC Pro probably has better compatibility with more arcade boards than the OSSC and RT2X).

[Pasky]

Has anyone found a solution for the screen curl also known as 'flagging' on the top of the screen when using some old consoles and arcade PCBs? Attached isn't my picture but it's the problem I have with CPS1/CPS2/PGM and numerous other boards when using this monitor. I was told running it through an extron would fix it with the serrated dip on but this does not solve my issue. At least not with with an Extron SC210 or an Extron 203.

If the serration switch doesn't work you'd have to do something a bit more radical like running the arcade boards through some converter/transcoder. With composite/s-video signals that have top flagging like this on these DT-V monitors my solution is to run them through a Retrotink 2X Pro or Multiformat in passthrough mode, and then converting the HDMI output to RGBHV with a DAC. You could probably do the same with an OSSC (or OSSC Pro) set to passthrough mode as well (the OSSC Pro probably has better compatibility with more arcade boards than the OSSC and RT2X).

Is there no H hold adjustment anywhere on the CRT?

[jd213]

Has anyone found a solution for the screen curl also known as 'flagging' on the top of the screen when using some old consoles and arcade PCBs? Attached isn't my picture but it's the problem I have with CPS1/CPS2/PGM and numerous other boards when using this monitor. I was told running it through an extron would fix it with the serrated dip on but this does not solve my issue. At least not with with an Extron SC210 or an Extron 203.

I recently saw someone on Twitter working on a RP2040 based sync regenerator to fix issues like this, but can't find the tweet right now.

[kitty666cats]

Has anyone found a solution for the screen curl also known as 'flagging' on the top of the screen when using some old consoles and arcade PCBs? Attached isn't my picture but it's the problem I have with CPS1/CPS2/PGM and numerous other boards when using this monitor. I was told running it through an extron would fix it with the serrated dip on but this does not solve my issue. At least not with with an Extron SC210 or an Extron 203.

I recently saw someone on Twitter working on a RP2040 based sync regenerator to fix issues like this, but can't find the tweet right now.

It was probably Shank, he posted something like that in a CRT Discord I’m in

[fernan1234]

Oh yeah it's this

https://github.com/Adewotta/PicoSync

Will probably fix the issue

[Pasky]

Oh yeah it's this

https://github.com/Adewotta/PicoSync

Will probably fix the issue

Interesting, I'm willing to give this a shot.

[Daloo]

Hello everyone!
I'm having some minor concerns about my JVC TM-H1950CG. I bought it half a year ago in great condition and apparently it wasn't used. Everything is fine with picture and overall, but it makes a low frequency noise when operating. I already read that it's okay for a lot of monitors especially of that age, but can I really do anything with it? It's seems to be the flyback transformer that makes this uncomfortable squeak

[Anonygoose]

Hey guys

I have a DTV1700CG that powered on once, then started giving an error where the D channel light starts to blink.

According to the service manual, it says X-rays detected and the problem is either IC801 or IC503.

I opened it up to have a look inside and noticed it arcs visibly during power up. Did a through clean but it didn't help.

I have a spare 1710CG with a dead tube for parts. I swapped the entire board assembly to the 1700 and it powered on just fine without any arcing.

I swapped IC503 from the working 1710CG to the 1700CG but same issue.

The problem is surely somewhere in the main board. Pretty confused as nothing is visibly damaged and nothing stood out while poking around with the Multimeter.

Any ideas?

[Tempest_2084]

I'm using GroovyArcade to output a 15KHz signal from my PC to my TM-H1750C monitor through an RGB card clone. I'm also using separate H and V syncs, but I'm having this issue with Csync as well. The picture looks amazing, but there's a flagging issue at the BOTTOM of the screen (not the top). I've tried hooking up an Extron 201 Rxi and selecting SERR to fix it, but it didn't have any effect. Any ideas what could be causing this?

[zer0dahero]

For anyone struggling with shaky signal from PS1 on the DTV1710, I have found a solution that works perfectly for me.
I'm converting RGB SCART to component with a retrotink RGB2COMP so that I can use the internal sync of the monitor instead of the ext. one.

I have tried both an extron RGB and a GBSC in passthru mode with no improvement, the signal was always very noticeably shaky/wobbly.
With the RGB2COMP it's rock solid, and the thing is not terribly expensive, so I highly recommend it. Now I'm wondering if it can also fix the flagging issues the PC Engine seems to have with this monitor? I would test it if I had one, but I don't