Plugging into RGBHV Scaler inputs

I am thinking about getting a signal converter to be able to capture LZX signals in high quality.

The one I am looking on is an Extron USP 405. It has RGBHV Inputs and I am wondering if it is possible to capture the RGB signals directly to get a higher quality output than the composite signal given by the Cadet II.

I have a Cadet I (I eventually got hold of one!) and can output horizontal and vertical sync signals to the Extron scaler, the only issue would be to find an adapter to convert the 3.5mm connectors on one end to BNC connectors on the other.

Is there any reason why this would not work?

We should be able to make it work. Do you have any soldering skills?

Yes soldering is not an obstacle. Also, Philip Baljeu also recently published a 3.5mm/BNC adapter module that could be useful in such a scenario.

So there are no issues regarding voltage levels or so? Should be compatible?

Since you plan on tapping into a Cadet II, I can only see one problem. Clipping and Blanking will be properly taken care of by the Cadet II, but IIRC the voltage level that is required by the SMT encoder chip is half of that required by a 75ohm device.
0.714Vp-p VS. 1.428Vp-p, so you will need to add a 2x gain buffer and add 75ohm series resistors for each R, G and B signal.

Now we’re getting closer I think. I never thought about having to tap into the Cadet II.

You mean what is missing from the “Patchable Video Standard” as defined here is clipping and blanking as well as something about voltage levels? Can you clarify what you mean regarding the SMT encoder?

So I cannot take rgb signals from let’s say a passage as well as the H+S sync signals from a Cadet I and plug into a RGBHV receiver?

(on closer thought maybe I should have asked this in the thread I mentioned…)

A thought came to me the other day, reinforced by this post… there is room in the market for a compact (ie 4-8hp) Component encoder module - for most of us that don’t own a Visual Cortex, ie to supplement a Cadet / Vidiot based system.

There is the Foundations series Encoder on the LZX roadmap, but would something like this be possible for the DIY crowd?

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The SMT encoder I was referring to is the surface mounted IC found on the Cadet II; the AD724.

You would not want to connect anything “directly” to the RGBHV receiver without going through a clipping circuit first. I believe that you are safe connecting H and V sync directly, but definitely not R, G and B luma. Also, H and V from the front of the Cadet I are 0-1V and some devices expect 5V. I’ll try to read about your device to see exactly what it expects.

Syntonie and I are both working on one, separately. From what I understand, his module will do direct RGB-luma to Component while I am working on a combination RGB-luma to RGsB (sync on green) and an RGB-to-Component converter. My RGsB encoder has been tested on an RGB-capable PVM and my Component converter works too but there are of course adjustments to be made before I can sell them.

I was thinking of sending eraxeg one of my prototype RGsB encoders if they are able to solder it themselves. They would just have to remove a single component to remove the sync on green and use some cable adapters.


I see. Thank you for explaining. I do not have the Extron device yet and I do not think I will get it now that I know things are more complicated than I thought.

I appreciate your offer to send me a prototype. However I doubt I would be able to help much since the only thing I have to test it with would be the same device as you mentioned, an RGB-capable PVM.