MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Information
Search is fixed!!! Apologies for the downtime.

3trins, V4 and a lack of color!
MUFF WIGGLER Forum Index -> Video Synthesis  
Author 3trins, V4 and a lack of color!
f4c3v4lu3
Having a strange issue with my 3trins and V4. I've figured out a fix, but wondering if anyone can shed light on what's happening.

Signal path:
3trins RCA composite out -> RCA-S-Video Adapter -> V4 S-video input (either)
Issue:
No color on the Output (Preview and Program)
I can see color when previewing the Input of the V4
I get color when using the same signal path and inputting to my AVE7
I get color when using the RCA composite input instead of the S-Video Input on the V4

Solution:
Insert a TBC in between the RCA to S-video adapter and the V4's S-video input
Just trying to sort out how/why the V4 is losing the color signal in between the input and the output...alternatively, I want to find the smallest TBC I can get affordably (rack units need not apply)

[note: the reason I'm using S-video instead of RCA composite into V4 is bcs there is an S-video routing matrix switcher in between...however, I've taken that out of the signal path and the issue remains]
f4c3v4lu3
Copying Over some discussion from a FB thread on this topic for future reference!

------------------------------------------------

Lars Larsen
Try adjusting the subcarrier frequency (green trimpot) on your 3trins. It could be out of the locking range for the V4. There could be compounding effect due to capacitance/delay caused by using this adapter. You may already know this, but you do not gain anything by putting your video through an RCA to S-Video adapter. In fact, this connector even if it has some sort of filtering inside, would only work properly as far as I can tell, if you were going S-Video to RCA. RCA to S-Video, how is it splitting chroma and Luma? (I'm guessing it's not, meaning you get some sort of bad filtering of the signal or CVBS just ends up on the Luma pin.)

------------------------------------------------

Me
Adjusting the "Burst" trimpot definitely has an effect on locking the color decoding in, but won't quite get all the way there...

Yea, I'm not going through the adapters for any type of quality gain - but rather so I can use a matrix router (http://www.hdtvsupply.com/rs8x8yc-a.html) that fell into my lap, but only has S-Video connections. Quite nice for multi-camera switching and re-routing signal paths between the two mixers, 3trins, bent-gear, etc on the fly.

Honestly, I haven't thought too much about what those adapters are actually doing to the video signal because before I got the V4, they were more or less plug-and-play with the Panasonic. Now I'm wondering how they're working at all!

I need to do some more research on Video Signal encoding theory...starting to build up a small collection of reference links (like this https://www.maximintegrated.com/.../app.../index.mvp/id/1184) but would love if you had any recommended reading smile

------------------------------------------------

Lars Larsen
CVBS = Composite Video Burst Sync. S-Video splits the burst and chroma subcarrier portions onto their own separate pin, so that Video+Sync are on one pin and Burst+Chroma are on another. If your adapter is a passive one I'm not sure how it works. Typically splitting burst+chroma from luma+sync involves a notch filter (for luma+sync) and bandpass filter (for burst+chroma) and then extra buffering because both pins in S-Video are driven at 75 ohms to 75 ohms termination. I'm guessing the S-Video to RCA just routes CVBS on the Luma pin and ignores the chroma pin. Regardless, any type of adapter at all is going to add some extra capacitance to the signal, which could introduce some phase delay into your chroma, putting it into a weird range -- I'm not sure. If you have any questions I'm happy to answer or troubleshoot.
evanh41
I lose color with my v4/3trins when the video sync is turned too high on the v4, use that preview out to dive into the menu.
MUFF WIGGLER Forum Index -> Video Synthesis  
Page 1 of 1
Powered by phpBB © phpBB Group