gscartsw / gscartsw_lite / gcompsw switches support thread

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tacameron
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by tacameron »

Super G is right on from what we (me,mike chi,superg) have been discussing. let it be known that the one LCD i tried with this exact chain didn't cause any of these display issues i'm currently hunting more crts with component for further testing aswell as flat panels also mike chi has some suggestions he wants me to try and ill post my findings soon.
TheJeffChen
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by TheJeffChen »

Hi superg,

I'm trying to build my own SCART to SCART cable to connect the switch to my TV. However the output voltage on pin 16 from the switch is only 1.8V and does not trigger the RGB mode on my TV.

Is it possible to bump it up somehow by modifying the switch? Or should I try to divide the 11V from pin 8 to achieve the voltage I need from inside the SCART connector itself?

Thank you.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

TheJeffChen wrote:Hi superg,

I'm trying to build my own SCART to SCART cable to connect the switch to my TV. However the output voltage on pin 16 from the switch is only 1.8V and does not trigger the RGB mode on my TV.

Is it possible to bump it up somehow by modifying the switch? Or should I try to divide the 11V from pin 8 to achieve the voltage I need from inside the SCART connector itself?

Thank you.
SCART specifications say that to trigger RGB mode, pin 16 should be 1-3V, 1.8V is right in the middle of this range so if TV doesn't switch - it's a TV problem :). 1.8V voltage regulator is one of the switch power rails, you can't just replace it with something else. And of course I would not modify the switch for something like this.

Actually, are you sure it doesn't switch? Maybe your TV just doesn't support such a feature?
Making a divider for pin 8 might work for you if you're sure that higher voltage would switch the mode.
TheJeffChen
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by TheJeffChen »

superg wrote: SCART specifications say that to trigger RGB mode, pin 16 should be 1-3V, 1.8V is right in the middle of this range so if TV doesn't switch - it's a TV problem :). 1.8V voltage regulator is one of the switch power rails, you can't just replace it with something else. And of course I would not modify the switch for something like this.

Actually, are you sure it doesn't switch? Maybe your TV just doesn't support such a feature?
Making a divider for pin 8 might work for you if you're sure that higher voltage would switch the mode.
There's a bit of story. My CRT is the Sony KV36FV300. It does not have SCART so I modified it and added one. Here are some pics. The blanking voltage for the jungle chip is a little bit above 2V, (because I added a diode to prevent voltage feedback from the TV's blanking pin), so I put a 270 Ohm to ground on the blanking pin, so that no matter which ever console get connected, either 12V or 5V coming to the blanking, with proper voltage divider resistors on the SCART side, the voltage should always be within the acceptable range and trigger the jungle chip into RGB mode.

Of course I didn't totally rely on external switching, so I also added a voltage divider from inside the TV from a 5V source, so I could force the TV into RGB mode with a flip of a switch.

At the moment, I can totally make the gscartsw work perfectly when I put my TV into forced RGB mode, but that obviously doesn't feel elegant enough :wink: ;)

What I'm thinking now is that maybe I could connect pin 8 from the switch to pin 16 on the TV, with a 800 Ohm resistor on the line, which would give me somewhat around 2.7V, then after the diode, drop to around 2V and correctly trigger RGB mode.

Any advice is appreciated, and thank you so much for the nice switch! :mrgreen:
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

TheJeffChen wrote: What I'm thinking now is that maybe I could connect pin 8 from the switch to pin 16 on the TV, with a 800 Ohm resistor on the line, which would give me somewhat around 2.7V, then after the diode, drop to around 2V and correctly trigger RGB mode.

Any advice is appreciated, and thank you so much for the nice switch! :mrgreen:
Oh, got it :).
Given that you're willing to make custom SCART male to male cable, pin8->pin16 with resistance would be the easiest solution in my opinion.
TheJeffChen
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by TheJeffChen »

superg wrote: Oh, got it :).
Given that you're willing to make custom SCART male to male cable, pin8->pin16 with resistance would be the easiest solution in my opinion.
Thanks for the advice!

I just tested and it seems a 680R worked fine. Now the TV is switching.

What I did was swapping pin 8 and 16 and added 680R on both of them (so the cable would work both ways).

My main concern was that I could be drawing too much power from pin 8 by doing this. Theoretically it's around 12mA and 0.1W. I hope it's not too much?
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

TheJeffChen wrote:
superg wrote: Oh, got it :).
Given that you're willing to make custom SCART male to male cable, pin8->pin16 with resistance would be the easiest solution in my opinion.
Thanks for the advice!

I just tested and it seems a 680R worked fine. Now the TV is switching.

What I did was swapping pin 8 and 16 and added 680R on both of them (so the cable would work both ways).

My main concern was that I could be drawing too much power from pin 8 by doing this. Theoretically it's around 12mA and 0.1W. I hope it's not too much?
12mA is fine.
TheJeffChen
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by TheJeffChen »

superg wrote: 12mA is fine.
Thanks. I'm gonna enjoy the switch from now on :wink:
jumpman1229
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by jumpman1229 »

I have a question regarding getting my gscartsw 5.2 to output a signal to my Extron RGB 203 rxi. I have a JVC DT-V 1710CG that has some flagging issues with sync from some consoles. I was told Extron devices fix this issue. I purchased both an Extron 160xi and a Extron RGB 203 rxi. Both of which are displaying "no signal." I have purchased both cables as seen below and cannot for the life of me get a signal from my gscartsw. Any ideas on why I'm not having any luck?

https://www.ebay.com/itm/MIST-MiSTer-MI ... 2749.l2649


And a cable made by retro-access:

https://retro-access.com/products/custo ... -builder-5

This cable is a SCART to VGA + audio cable
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the Goat
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by the Goat »

jumpman1229 wrote:I have a question regarding getting my gscartsw 5.2 to output a signal to my Extron RGB 203 rxi. I have a JVC DT-V 1710CG that has some flagging issues with sync from some consoles. I was told Extron devices fix this issue. I purchased both an Extron 160xi and a Extron RGB 203 rxi. Both of which are displaying "no signal." I have purchased both cables as seen below and cannot for the life of me get a signal from my gscartsw. Any ideas on why I'm not having any luck?

https://www.ebay.com/itm/MIST-MiSTer-MI ... 2749.l2649


And a cable made by retro-access:

https://retro-access.com/products/custo ... -builder-5

This cable is a SCART to VGA + audio cable
Your first link shows a cable that goes the wrong direction, VGA to SCART. You need SCART to VGA. I'm not sure what cable you got from retro-access. You linked to their custom cable builder page.

Extron devices like pure composite sync (csync), not composite video or luma.
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jumpman1229
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by jumpman1229 »

the Goat wrote:
jumpman1229 wrote:I have a question regarding getting my gscartsw 5.2 to output a signal to my Extron RGB 203 rxi. I have a JVC DT-V 1710CG that has some flagging issues with sync from some consoles. I was told Extron devices fix this issue. I purchased both an Extron 160xi and a Extron RGB 203 rxi. Both of which are displaying "no signal." I have purchased both cables as seen below and cannot for the life of me get a signal from my gscartsw. Any ideas on why I'm not having any luck?

https://www.ebay.com/itm/MIST-MiSTer-MI ... 2749.l2649


And a cable made by retro-access:

https://retro-access.com/products/custo ... -builder-5

This cable is a SCART to VGA + audio cable
Your first link shows a cable that goes the wrong direction, VGA to SCART. You need SCART to VGA. I'm not sure what cable you got from retro-access. You linked to their custom cable builder page.

Extron devices like pure composite sync (csync), not composite video or luma.
The cable I built on retro access had a SCART source connector and a dsub 15 with 3.5mm destination connector. But you're right, I just realized I bought the wrong direction cable from eBay.. doh!

All of my consoles feeding into the gscartsw are csync I believe. With the sync stripping, wouldn't that clean up the signal for the Extron anyways? It did with my Crosspoint
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

jumpman1229 wrote: All of my consoles feeding into the gscartsw are csync I believe. With the sync stripping, wouldn't that clean up the signal for the Extron anyways? It did with my Crosspoint
Well, if all your consoles are CSYNC anyway, there is nothing to clean with sync regeneration really. But I remember some Extron devices didn't like 75ohm terminated csync with cvbs level.
rebornkid
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by rebornkid »

Hey there,

i'am Serge from Switzerland and I orderd today a gscartsw. Did I get an order confirmation?
I hope with the gscartsw all the issues with the pc engine due r are history. 8)
rebornkid
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by rebornkid »

Hey there,

my name is Serge from switzerland.
I ordered today an gscartsw. I hope with this gadget, my issues with my pc engine duo r are history. At some pce-games, I get a black screen for a second.
By the way, do I get an order confirmation for the gscartsw.? Until now, i received nothing.
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the Goat
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by the Goat »

rebornkid wrote: I hope with this gadget, my issues with my pc engine duo r are history.
PC Engine Duo doesn't have RGB out from the factory. So it 100% depends on what RGB mod you have installed.
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rebornkid
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by rebornkid »

the Goat wrote:
rebornkid wrote: I hope with this gadget, my issues with my pc engine duo r are history.
PC Engine Duo doesn't have RGB out from the factory. So it 100% depends on what RGB mod you have installed.
Yes, I know, but I didn’t modifie it by myself. So i don’t know which mod is installed. When i connect the pce direct to the pvm2950qm it works perfect. When my scart switch is installed, the issues starts.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

rebornkid wrote:Hey there,

my name is Serge from switzerland.
I ordered today an gscartsw. I hope with this gadget, my issues with my pc engine duo r are history. At some pce-games, I get a black screen for a second.
By the way, do I get an order confirmation for the gscartsw.? Until now, i received nothing.
Hi Serge,
If you see the paypal transaction it means that order went through. I see the transaction here.
There might be issues with PC Engine, this is problematic console, as others pointed out, it depends on which mod you're going to use on it. One thing I remember that dbGrafx Booster was good.
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Gara
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Gara »

jumpman1229 wrote:I have a question regarding getting my gscartsw 5.2 to output a signal to my Extron RGB 203 rxi. I have a JVC DT-V 1710CG that has some flagging issues with sync from some consoles. I was told Extron devices fix this issue. I purchased both an Extron 160xi and a Extron RGB 203 rxi. Both of which are displaying "no signal." I have purchased both cables as seen below and cannot for the life of me get a signal from my gscartsw. Any ideas on why I'm not having any luck?

https://www.ebay.com/itm/MIST-MiSTer-MI ... 2749.l2649


And a cable made by retro-access:

https://retro-access.com/products/custo ... -builder-5

This cable is a SCART to VGA + audio cable
When building the custom cable, did you include a LM1881 sync stripper in the design? The Extron will not take your various RGB consoles without the sync stripper.

You'll have to have one installed in your current cable. There wasn't options for having custom cables made when I did my setup, so I use a sync strike to get the signal in to my Extron 203.

http://arcadeforge.net/Scaler-and-Strik ... e::15.html
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

Gara wrote: When building the custom cable, did you include a LM1881 sync stripper in the design? The Extron will not take your various RGB consoles without the sync stripper.

You'll have to have one installed in your current cable. There wasn't options for having custom cables made when I did my setup, so I use a sync strike to get the signal in to my Extron 203.

http://arcadeforge.net/Scaler-and-Strik ... e::15.html
You don't need sync stripper anywhere as gscartsw has it integrated.
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Gara
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Gara »

superg wrote:
Gara wrote: When building the custom cable, did you include a LM1881 sync stripper in the design? The Extron will not take your various RGB consoles without the sync stripper.

You'll have to have one installed in your current cable. There wasn't options for having custom cables made when I did my setup, so I use a sync strike to get the signal in to my Extron 203.

http://arcadeforge.net/Scaler-and-Strik ... e::15.html
You don't need sync stripper anywhere as gscartsw has it integrated.
I couldn't get my Extron 203 to accept the signal without a sync stripper built into the Scart to VGA adapter. All my testing was with the gscartsw_lite. I tried with a direct connection as well. Are you getting a different result with the Extron RGB RXI units when feeding it 15khz RGB from various consoles?
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

Gara wrote: I couldn't get my Extron 203 to accept the signal without a sync stripper built into the Scart to VGA adapter. All my testing was with the gscartsw_lite. I tried with a direct connection as well. Are you getting a different result with the Extron RGB RXI units when feeding it 15khz RGB from various consoles?
It's not the sync stripping that helped you, it's higher level / TTL sync you get after LM1881 because that is not usually brought back down in all those cables. If you turn on sync regeneration (or CS on lite) it already cleans the signal, if you do it again with LM1881, you introduce more lag and more processing to your signal which is something you should avoid.
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Gara
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Gara »

superg wrote:
Gara wrote: I couldn't get my Extron 203 to accept the signal without a sync stripper built into the Scart to VGA adapter. All my testing was with the gscartsw_lite. I tried with a direct connection as well. Are you getting a different result with the Extron RGB RXI units when feeding it 15khz RGB from various consoles?
It's not the sync stripping that helped you, it's higher level / TTL sync you get after LM1881 because that is not usually brought back down in all those cables. If you turn on sync regeneration (or CS on lite) it already cleans the signal, if you do it again with LM1881, you introduce more lag and more processing to your signal which is something you should avoid.
I tried toggling the switch back when I did the testing. It didn't make a difference. Is there some other solution to this problem that I am missing? How else do I raise the sync level? I'd love to remove the LM1881 from my chain, but I couldn't make it work. I usually keep sync regeneration off with my Gscartsw.

With RGB I thought it was pretty universal that you have to use a sync stripper on the adapter when you're dealing with the Extron RGB Rxi. Even with a Gscartsw.
Maybe something else was causing me issues.
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Lord Arse!
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Lord Arse! »

<double post - please ignore>
Last edited by Lord Arse! on Mon Jan 13, 2020 8:46 pm, edited 1 time in total.
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LordA
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by LordA »

Was umming and awwing over getting one of these or a Hydra for ages to compliment my OSSC. Finally bought the gscartsw on Sunday!
Can't wait to get my hands on it. Is there a chance I'll make it into the late-January batch? *fingers crossed*
Renaissance2K
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Renaissance2K »

Hi, everyone. Happy owner of multiple gSwitches here with a couple of questions.

1. Are replacement power supplies of suitable quality available on Amazon US? I think one of my supplies got inadvertently tossed in a cleaning run.

2. I'm trying to connect my PS2 (Phat) to a gcompsw using an HD Retrovision PS2/3 cable. The green status LED on the gcompsw quickly blinks whenever the PS2 is on and connected, and there is no video signal. The video works fine when connected directly to my TV, to an OSSC, or to an xRGB Mini. I've triple-checked my connections and tried connecting the console to a different input on the switch. Any other ideas?

Thanks a lot.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

Renaissance2K wrote:Hi, everyone. Happy owner of multiple gSwitches here with a couple of questions.

1. Are replacement power supplies of suitable quality available on Amazon US? I think one of my supplies got inadvertently tossed in a cleaning run.

2. I'm trying to connect my PS2 (Phat) to a gcompsw using an HD Retrovision PS2/3 cable. The green status LED on the gcompsw quickly blinks whenever the PS2 is on and connected, and there is no video signal. The video works fine when connected directly to my TV, to an OSSC, or to an xRGB Mini. I've triple-checked my connections and tried connecting the console to a different input on the switch. Any other ideas?

Thanks a lot.
1. Which switch and version do you need power supply for?
2. Should not be a problem. Switch detects and forwards the signal because the LED blinks. Did you switch XRGB input modes and made sure PS2 is set to YPbPr?
Renaissance2K
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by Renaissance2K »

superg wrote:1. Which switch and version do you need power supply for?
gscartsw v5.2
superg wrote:2. Should not be a problem. Switch detects and forwards the signal because the LED blinks. Did you switch XRGB input modes and made sure PS2 is set to YPbPr?
You're right. The console was previously hooked up via SCART, so it was set to RGB. I'll surrender my nerd card at your earliest convenience.
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

Renaissance2K wrote:gscartsw v5.2
Oh, the latest it's really just any micro usb charger. Pick what you like, just don't go the cheapest.
Renaissance2K wrote: You're right. The console was previously hooked up via SCART, so it was set to RGB. I'll surrender my nerd card at your earliest convenience.
Sometimes I make the same mistake, keep your card :)
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redhotsonic
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by redhotsonic »

Hello, there. Big fan of these switch boxes. I have both the gscartsw and gcompsw and they work perfectly for all of my consoles! Well, almost. In fact, that is why I am here to ask this (probably stupid) question!

All my RGB SCART and Component consoles work brilliantly. However, I have two consoles that are composite only (well, modified from RF. A ZX Spectrum 48k (PAL) and a Sega SG-1000 (NTSC-J). I was led to believe that the gcompsw can take composite signal. However, I cannot get a picture via this switcher.

Using the ZX as an example (both consoles act the same), I plug the console via a composite cable into the yellow composite input of the gcompsw. Then I input another composite cable into the yellow composite output of the gcompsw and into my Sony PVM’s (PVM-20M2MDE) composite input. However, when switching the console on, the PVM starts going haywire with a thick white line scrolling diagonally up with a blank picture; as if it is really struggling to get a picture.

After reading superg’s gcompsw page, unless I am confused, maybe the green inputs need to be used instead? I have tried mixing and matching but I get either nothing, or the sync issue. If I try my Framemeister [FM] instead of my PVM, nothing happens at all and the FM stays blue.

I have tried different composite cables, mixed and matched with the composite/component inputs/outputs on both the gcompsw and PVM/FM and I get nothing. In addition, in case you are wondering, if I plug either of these consoles directly into the PVM or FM and bypass the gcompsw, I get a picture and it works perfectly. But then I am without a switcher.

Is there something I am doing wrong? Or am I misunderstood that the gcompsw can do composite? Any advice would be greatly appreciated :)

Thanks!

EDIT: I forgot to mention in case this information is needed, but I have the gcompsw version 5.2
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superg
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Re: gscartsw / gscartsw_lite / gcompsw switches support thre

Post by superg »

redhotsonic wrote:Hello, there. Big fan of these switch boxes. I have both the gscartsw and gcompsw and they work perfectly for all of my consoles! Well, almost. In fact, that is why I am here to ask this (probably stupid) question!

All my RGB SCART and Component consoles work brilliantly. However, I have two consoles that are composite only (well, modified from RF. A ZX Spectrum 48k (PAL) and a Sega SG-1000 (NTSC-J). I was led to believe that the gcompsw can take composite signal. However, I cannot get a picture via this switcher.

Using the ZX as an example (both consoles act the same), I plug the console via a composite cable into the yellow composite input of the gcompsw. Then I input another composite cable into the yellow composite output of the gcompsw and into my Sony PVM’s (PVM-20M2MDE) composite input. However, when switching the console on, the PVM starts going haywire with a thick white line scrolling diagonally up with a blank picture; as if it is really struggling to get a picture.

After reading superg’s gcompsw page, unless I am confused, maybe the green inputs need to be used instead? I have tried mixing and matching but I get either nothing, or the sync issue. If I try my Framemeister [FM] instead of my PVM, nothing happens at all and the FM stays blue.

I have tried different composite cables, mixed and matched with the composite/component inputs/outputs on both the gcompsw and PVM/FM and I get nothing. In addition, in case you are wondering, if I plug either of these consoles directly into the PVM or FM and bypass the gcompsw, I get a picture and it works perfectly. But then I am without a switcher.

Is there something I am doing wrong? Or am I misunderstood that the gcompsw can do composite? Any advice would be greatly appreciated :)

Thanks!

EDIT: I forgot to mention in case this information is needed, but I have the gcompsw version 5.2
You connected it right the first time, input to yellow RCA and output from yellow RCA.
Interesting, my ZX Spectrum clone here works fine (at least that's what I remember when I had it connected some time ago). Without seeing the actual sync signal it's hard to say what's going on. gcompsw doesn't process the signal, two things could have happened:
1. gcompsw drops the signal, check LED, it will quickly blink once when it detects the input. If you see constant blinking it means that the sync is unstable.
2. amplitude problem, multiplexer chips range is -5V..5V, if something is above / under, it will be cut, that includes the situation when your level is shifted.
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