2023/05/11

[English] A short review of pro-grade A/V switcher and its supported input resolutions.

These results provide information for retro gaming enthusiasts who want to record or live stream while switching between multiple sources.

Please note that these results are not guaranteed for all low resolution signals. The sync signal/timing may be degraded due to deterioration over time the capacitors and chips. This can be fixed by replace them with compatible new part or signal correction via multiple step of sync cleaner and video buffer chips. (search keyword for sync cleaner : LM1881, EL1883 or EL4511)

It is important to note that both 24k and 31k refer to common resolution of 512x384p and 640x480p. Uncommon any other special resolution such as 512x512, 512x256, 1024x1024 has not been tested.

15k@240p include some vertical resolution of 224p used in some console game or arcade pcb.


1. Extron ISS 506 Scalers & Signal Processor (USA)


- No OSD-overlay available. Use small front LCD for control or web, remote control.
- No auto-identification of signal type function. It must be set manually.
- Audio connector is not user-friendly.
- EDID emulator is implemented.
- 6 input / 1 output (BNC + DSUB + option port for program and DSUB for preview simultaneously)
- Output upscale : up to 1920x1200p60 reduced blanking or 1920x1080p60
- Input-Output latency : approx. 1.5frame(measured on 1080p60 source-1080p60 output)
- Audio connector : Phoenix contact MC 1,5/5-ST-3,5. 3.5mm pitch (Mft. part# 1840395)
- Open source 3.5mm stereo jack adapter : GitHub - phoenix-audio-adapter 
  (It's an open source shared kicad scheme. Do NOT disturb him/her.)

Acceptable resolution
Resolution RGBHV RGBS Component S-Video Composite
15k@240p Ok Ok Ok Ok Ok
15k@480i Ok Ok Ok Ok Ok
24k Ok Ok ? (Ok?) - -
31k@480p Ok Ok Ok - -
above~ Ok Ok Ok - -






OSD-overlay available.
- Power connector is not user-friendly.
- EDID emulator is implemented.
- Power connector : Phoenix contact MC 1,5/2-ST-3,5. 3.5mm pitch (Mft. part# 1840395)
- Although 15k@240p RGBS is acceptable, it is forced to be recognized as 15k@480i, which can cause line-artifact noise during blend-method deinterlace processing.

Analog DSUB15 pin assignment
1 : Red, R-Y (Pr)
2 : Green, Luma (Y)
3 : Blue, R-B (Pb)
13 : HSync, CSync
14 : VSync


Acceptable resolution
Resolution RGBHV RGBS Component S-Video Composite
15k@240p Ok※1 Ok※1 ? Monochrome Monochrome
15k@480i Ok Ok Ok Monochrome Monochrome
24k Ok Ok ? - -
31k@480p Ok Ok Ok - -
above~ Ok Ok Ok - -

※1: Recognized as 480i. Artifact (by blend-method deinterlaced?) occurred on the screen. If you dislike this, use other equipment that supports Yadif(a.k.a. adaptive method) or bob method functions.





- OSD-overlay is available.
Automatic signal type identification
- EDID emulator is implemented.
- 6 input / 1 output ( DVI-I + HDMI simultaneously) 
Analog video input : DVI-I, HD-DSUB15 (both can be accept YPbPr/YC/CVBS)
Digital video input : HDMI (DVI/HDMI)

Analog DSUB15 pin assignment (DVI-I port can also be used with a DSUB adapter)
1 : Red, R-Y (Pr)
2 : Green, Luma (Y), Composite
3 : Blue, R-B (Pb), Chroma (C)
13 : HSync, CSync
14 : VSync

Acceptable resolution
Resolution RGBHV RGBS Component S-Video Composite
15k@240p Failed ※2 Failed ※2 Failed ※2Monochrome Ok
15k@480i Ok Ok Ok Ok Ok
24k Ok Ok ? (Ok?) - -
31k@480p Ok Ok Ok - -
above~ Ok Ok Ok - -

※2: Half sized screen displayed; it recognized as 15k@640x480p. This should be cropped on the bottom side later using another method.




- OSD-overlay is available.
- Automatic signal type identification
- 1 analog in / 2 digital out with upscaler and image processing (crop/resize/rotate/...)
- EDID emulator is implemented.

Analog DSUB15 pin assign
1 : Red, R-Y (Pr)
2 : Green, Composite
3 : Blue, R-B (Pb)
13 : HSync, CSync
14 : VSync

Acceptable resolution
Resolution RGBHV RGBS Component S-Video Composite
15k@240p Ok ※1 Ok ※1 Ok ※1 Monochrome Monochrome
15k@480i Ok Ok Ok Monochrome Ok
24k Ok Ok ? - -
31k@480p Ok Ok Ok - -
above~ Ok Ok Ok - -

※1 recognized as 480i. Artifact (by blend-method deinterlaced?) occurred on the screen. If you dislike this, use other equipment that supports Yadif(a.k.a. adaptive method) or bob method functions.