JAG2GEN Information & Troubleshooting

Technical Specs

Output SignalsAudio L & R, Audio Mono, CSYNC, RGB, Composite Video, 5v
Output Resolution240p*
Voltage Output5v
Current Output100-150mV
Sync TypeCSYNC attenuated for use with a Genesis 2 SCART cable
Supported CablesHD Retrovision Genesis YPbPr Component Cable (Recommended), Genesis Model 2 SCART**, Genesis Model 2 composite cables
Tested ScalersList will be updated as we are able to test more scalers:
GBS Control, OSSC, RetroTINK 2x Pro, RetroTINK 5x Pro
Untested ScalersConsider these unsupported
Rad2x, Framemeister

*Some modern HDTVs aren’t able to display 240p signal, the native video resolution of the Atari Jaguar. It is not a limitation of the JAG2GEN but rather your TV. To support your Atari Jaguar on a TV that does not support 240p signal, you should consider buying a scan converter of some kind.
**SCART cable components vary. Some use CSYNC other use Composite on SYNC and most filter the RGB signals. If you plan to use a SCART cable with the JAG2GEN, you may need to modify the cable to work properly with the Atari Jaguar as they were intended to be used with the Sega Genesis. This isn’t a limitation of the JAG2GEN but rather an expectation of SCART and the Jaguar’s RGB and Sync lines.

FAQ

What is the JAG2GEN?
The JAG2GEN is an adapter that simply converts your Jaguar’s AV signal to that of a Genesis (model 2 or 3*) AV cable.

Will it make the Atari Jaguar’s picture quality look better
The JAG2GEN does not upscale the native 240p signal from the Atari Jaguar. It does however provides the best analog output (RGB) from the console. The Atari Jaguar already provides the proper 75ohm RGB out and the JAG2GEN outputs those same signals directly through a more common 9-pin mini din (Genesis 2) socket. For razer sharp pixels, we highly recommend using the JAG2GEN with a modern scaler like the OSSC or RetroTINK 5x to get the best picture quality.

What type of Sync is used in the JAG2GEN?
The Atari Jaguar outputs TTL level CSYNC natively. The JAG2GEN attenuates the native Atari Jaguar CSYNC voltage difference to equal the expected 75ohm output. Because the JAG2GEN is intended to be used with Sega Genesis 2 cables, there should be a 470ohm resistor and 220uf capacitor inline on the SCART cable you’re using.

What are OSSC optimal timings for the Atari Jaguar?
OSSC Profiles will need some tweaking to fit your TV and Cable needs. Here is a good starting point:

Video in proc
Video LPF = 35MHz

Sync opt.
Analog sync LPF = 10MHz (med)
Analog Sync Vth = 180 mV (Only for SCART with CSYNC)

Output opt.
240p/288p proc = Whatever lineX mode you prefer.
LineXx mode = 320×240 optimal

Sampling opt.
Adv. timing > 320×240:
H. samplerate = 422
H. synclen = 31
H. backporch = 23
H. active = 360
V. synclen = 3
V. backporch = 11
V. active = 240
Sampling phase = 303 (this can vary)

Credit: FirebrandX

Troubleshooting & Known Issues

  1. Darker picture with SCART cable
  2. Grid like pattern on some colors
  3. Rainbow colored dots or patterns
  4. Flickering while using RetroTINK
  5. Distortion or “waves” across the screen
  6. Smearing or blurring on light to dark colored objects

Darker picture with SCART cable

Impacts SCART cables

  • Due to how Sega designed the Sega Genesis, Genesis SCART cables required components inside the cables to properly attenuate the RGB signals. Ultimately, these components lower the brightness when using a properly built Genesis 2 SCART cable with JAG2GEN. The simple work around would be to use the brightness settings on your particular screen.

Image capture from RetroRGB

There is a grid like pattern on some or all colors

Impacts Composite, S-Video, and some SCART cables

  • Cable: Any sort of artifacts on images is typically due to poor cable quality. The first thing you should do is try to rule out your current cable with a new one.
  • Scaler: Some scalers will add additional processing to the images causing artifacts. Scalers also take any poor video quality and upscale them making them more noticeable. Try to adjust the scalers settings to mitigate the processing of the image.

Image is a representation of the issue

There is a rainbow pattern around some objects

Typically impacts Composite and some S-Video cables

  • Composite Video: Dot Crawl and “rainbow” video noise is inherent to Composite Video Source. Even with perfectly good composite cables, you will most likely still see this issue. It is typical of the video source.
  • Scaler: In combination with composite video source, scalers can make this issue more apparent since you are taking a video signal with noise and upscaling it.

Image is a representation of the issue

Flickering screen on some games when using a RetroTINK

Typically impacts HD Retrovision and SCART cables

  • Comb filter: If you’re experiencing flickering in some games while using the RetroTINK, slide the “COMB” switch to “Retro” to help mitigate this.

Intermittently “waves” or distortion across the screen

Typically impacts cheap SCART cables

  • Cables: Cheaply made SCART cables typically aren’t shielded or grounded properly. Without proper ground or shielding, you will see noticeable cross talk or wave like distortions on the screen.
  • DC Power Adapter: Old or cheaply made DC power adapters can cause visual noise in the picture.
  • Internal Components: One or more internal components like Capacitors and/or voltage regulators could be bad in your console.

Image is a representation of the issue

Smearing or blurring on light to dark colored objects

Typically impacts SCART, S-Video cables, untested Scalers

  • Cables: Cheaply made SCART and S-Video cables can cause an afterimage “smearing” effect where a light and dark object intersect. As always, make sure you’re using good quality cables. The photo shows Insurrection SCART cables through an OSSC set to “Generic 4:3”.
  • Scaler: we’ve heard that some scalers are causing this issue. Specifically the Framemeister. We can’t confirm this ourselves because we have don’t have a Framemeister for testing, which is why we consider it unsupported. The photo in this section is NOT an output of the Framemeister.
  • Scaler Timing: scaler settings like Sampling Phase can sometimes cause this. See the above OSSC settings as a guide.