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Hello all, I just picked up a pretty good condition SMS1 yesterday and hooked it up to my BVM without a cartridge installed, but seems to have a screen tearing issue on the top 1/3 of the screen! Unfortunately I don't have any carts to try out as they had no SMS games in stock. I've included a pictures of the caps and video issue I'm having.

I don't see any goop on the motherboard, no water damage or signs of corrosion either. Board is relatively clean. Trying to locate my Genesis 1 composite cables to see if the issue still exists. To my knowledge, the Genesis 1 and SMS1 use the same RGB cables, right?

Photo Jan 29 12 05 39 AM.jpg (221.54 KB)

screen tearing

Photo Jan 29 12 01 07 PM.jpg (146.1 KB)

Photo Jan 29 12 00 42 PM.jpg (192.89 KB)

Photo Jan 29 12 00 35 PM.jpg (183.08 KB)

Photo Jan 29 12 00 23 PM.jpg (233.29 KB)

Photo Jan 29 12 00 29 PM.jpg (182.84 KB)

Looks like it could be a sync issue?

The MD/GEN model one does use the same multi out connector. The MD/GEN/SMS all have its own separate sync line "CSYNC"

Is the cable you're using an official cable or aftermarket?

There are diagrams for scart pinouts online. Just Google "SMS SCART PINOUT"

k4l wrote

Looks like it could be a sync issue?

The MD/GEN model one does use the same multi out connector. The MD/GEN/SMS all have its own separate sync line "CSYNC"

Is the cable you're using an official cable or aftermarket?

There are diagrams for scart pinouts online. Just Google "SMS SCART PINOUT"

I'm using retro cable accessories' GEN1 - BNC cable. Works like a dream on my Genesis1. If I hit the External Sync button, the image starts rolling. All the cables and wires are hooked up as they should be. My Gen1, NES, and SNES all work awesome with my setup. The SMS is the only one throwing me for a loop with this issue.

I guess you might want to either tune in the RF to a TV or find a composite cable. If that has the same fault it could be chips on the Sega board. If there is no damage to the chips check the tracers on the board

UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue.

Any insight?

ltwm3 wrote

UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue.

Any insight?
...
[/URL]

Try replacing the electrolytic capacitor on composite line.

Also, regarding seeing no leakage... this proves nothing about a capacitor. To check it accurately you would need like an old tube-based capacitor tester or an ESR meter. Apparently some low-voltage digital capacitor testers exist, and if the cap is 16V or lower you might be able to use it accurately.

If you replace the cap you have to fully replace it. You can't just wire one in parallel to test.

Neto wrote

ltwm3 wrote

UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue.

Any insight?
...
[/URL]

Try replacing the electrolytic capacitor on composite line.

Do you know the location of this capacitor? Also, is there a way for me to test the output voltage to see if it's in spec?

ltwm3 wrote

Neto wrote

ltwm3 wrote

UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue.

Any insight?
...
[/URL]

Try replacing the electrolytic capacitor on composite line.

Do you know the location of this capacitor? Also, is there a way for me to test the output voltage to see if it's in spec?

For testing video signal an oscilloscope is recommended.
I have pointed the location of capacitor in attachment.

CVBS Capacitor.jpg (38.18 KB)

composite vídeo capacitor

Just saw these posts now!

Is there a complete comprehensive capacitor replacement kit for the SMS1 that would include that capacitor? Are there different types/qualities of capacitors I should be looking out for?

Thanks!

If you are in the US: https://console5.com/store/kits/console-cap-kits/sega/master-system.html

If not, then just look at the values. I don't think there's too many of them. Just get any Panasonic, Nichicon or Rubycon 'lytics. 85C will be cheaper, but 105C would possibly last longer. Up to you.

Don't bother replacing the ceramics unless they really need it.

The BVM is having an issue due to the horizontal slices in the video. If yours is a D-series, just turn on "VCR Mode". If not, you can combine devices for a solution (580xi after the crosspoint?). These videos and page show the issue on an A-series BVM, but I've seen it on others as well (it also happens on my 14"):

http://www.retrorgb.com/bkm-68x.html

Thanks fellas. I have a D series BVM. RetroRGB, if I put an RGB bypass in from Retrofixes, will that clean it up without having to use another external device? Also, why does this happen?

Author	Message
ltwm3 Joined: 29 Jan 2017 Posts: 6	Diagnosing SMS1 video issue Posted: Sun Jan 29, 2017 5:24 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	Hello all, I just picked up a pretty good condition SMS1 yesterday and hooked it up to my BVM without a cartridge installed, but seems to have a screen tearing issue on the top 1/3 of the screen! Unfortunately I don't have any carts to try out as they had no SMS games in stock. I've included a pictures of the caps and video issue I'm having. I don't see any goop on the motherboard, no water damage or signs of corrosion either. Board is relatively clean. Trying to locate my Genesis 1 composite cables to see if the issue still exists. To my knowledge, the Genesis 1 and SMS1 use the same RGB cables, right? Photo Jan 29 12 05 39 AM.jpg (221.54 KB) screen tearing Photo Jan 29 12 01 07 PM.jpg (146.1 KB) Photo Jan 29 12 00 42 PM.jpg (192.89 KB) Photo Jan 29 12 00 35 PM.jpg (183.08 KB) Photo Jan 29 12 00 23 PM.jpg (233.29 KB) Photo Jan 29 12 00 29 PM.jpg (182.84 KB)

k4l Joined: 14 Mar 2016 Posts: 58 Location: Australia	Posted: Sun Jan 29, 2017 6:27 pm
k4l Joined: 14 Mar 2016 Posts: 58 Location: Australia	Looks like it could be a sync issue? The MD/GEN model one does use the same multi out connector. The MD/GEN/SMS all have its own separate sync line "CSYNC" Is the cable you're using an official cable or aftermarket? There are diagrams for scart pinouts online. Just Google "SMS SCART PINOUT"

ltwm3 Joined: 29 Jan 2017 Posts: 6	Posted: Sun Jan 29, 2017 6:49 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	k4l wrote Looks like it could be a sync issue? The MD/GEN model one does use the same multi out connector. The MD/GEN/SMS all have its own separate sync line "CSYNC" Is the cable you're using an official cable or aftermarket? There are diagrams for scart pinouts online. Just Google "SMS SCART PINOUT" I'm using retro cable accessories' GEN1 - BNC cable. Works like a dream on my Genesis1. If I hit the External Sync button, the image starts rolling. All the cables and wires are hooked up as they should be. My Gen1, NES, and SNES all work awesome with my setup. The SMS is the only one throwing me for a loop with this issue.

k4l Joined: 14 Mar 2016 Posts: 58 Location: Australia	Posted: Sun Jan 29, 2017 7:03 pm
k4l Joined: 14 Mar 2016 Posts: 58 Location: Australia	I guess you might want to either tune in the RF to a TV or find a composite cable. If that has the same fault it could be chips on the Sega board. If there is no damage to the chips check the tracers on the board

ltwm3 Joined: 29 Jan 2017 Posts: 6	Posted: Sun Jan 29, 2017 7:11 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue. Any insight?

Neto Joined: 04 Dec 2016 Posts: 44 Location: Guarulhos - SP - Brasil	Posted: Tue Jan 31, 2017 2:28 am
	ltwm3 wrote UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue. Any insight? ... [/URL] Try replacing the electrolytic capacitor on composite line.

Maraakate Joined: 05 Jun 2010 Posts: 757 Location: Pennsylvania, USA	Posted: Wed Feb 01, 2017 1:18 am
	Also, regarding seeing no leakage... this proves nothing about a capacitor. To check it accurately you would need like an old tube-based capacitor tester or an ESR meter. Apparently some low-voltage digital capacitor testers exist, and if the cap is 16V or lower you might be able to use it accurately. If you replace the cap you have to fully replace it. You can't just wire one in parallel to test.

ltwm3 Joined: 29 Jan 2017 Posts: 6	Posted: Wed Feb 01, 2017 12:51 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	Neto wrote ltwm3 wrote UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue. Any insight? ... [/URL] Try replacing the electrolytic capacitor on composite line. Do you know the location of this capacitor? Also, is there a way for me to test the output voltage to see if it's in spec?

Neto Joined: 04 Dec 2016 Posts: 44 Location: Guarulhos - SP - Brasil	Posted: Fri Feb 03, 2017 7:03 pm
	ltwm3 wrote Neto wrote ltwm3 wrote UPDATE: So I hooked the SMS up through the Crosspoint and output the video signal to the XRGB Mini and the BVM, XRGB has no issue with the video signal and works perfect. The BVM is still having an issue. Any insight? ... [/URL] Try replacing the electrolytic capacitor on composite line. Do you know the location of this capacitor? Also, is there a way for me to test the output voltage to see if it's in spec? For testing video signal an oscilloscope is recommended. I have pointed the location of capacitor in attachment. CVBS Capacitor.jpg (38.18 KB) composite vídeo capacitor

ltwm3 Joined: 29 Jan 2017 Posts: 6	Posted: Tue Aug 22, 2017 4:06 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	Just saw these posts now! Is there a complete comprehensive capacitor replacement kit for the SMS1 that would include that capacitor? Are there different types/qualities of capacitors I should be looking out for? Thanks!

Maraakate Joined: 05 Jun 2010 Posts: 757 Location: Pennsylvania, USA	Posted: Tue Aug 22, 2017 10:09 pm
	If you are in the US: https://console5.com/store/kits/console-cap-kits/sega/master-system.html If not, then just look at the values. I don't think there's too many of them. Just get any Panasonic, Nichicon or Rubycon 'lytics. 85C will be cheaper, but 105C would possibly last longer. Up to you. Don't bother replacing the ceramics unless they really need it.

RetroRGB Joined: 23 Apr 2014 Posts: 131 Location: NYC	Posted: Wed Aug 23, 2017 1:39 pm
RetroRGB Joined: 23 Apr 2014 Posts: 131 Location: NYC	The BVM is having an issue due to the horizontal slices in the video. If yours is a D-series, just turn on "VCR Mode". If not, you can combine devices for a solution (580xi after the crosspoint?). These videos and page show the issue on an A-series BVM, but I've seen it on others as well (it also happens on my 14"): http://www.retrorgb.com/bkm-68x.html

ltwm3 Joined: 29 Jan 2017 Posts: 6	Posted: Mon Aug 28, 2017 7:05 pm
ltwm3 Joined: 29 Jan 2017 Posts: 6	Thanks fellas. I have a D series BVM. RetroRGB, if I put an RGB bypass in from Retrofixes, will that clean it up without having to use another external device? Also, why does this happen?

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