The AVT-8120 is a quad splitter that can contain some of the same chips as found on the AVT-8710 and 1T-TBC/1T-TBC-GL. It's a composite only unit, no s-video (Y/C), and has BNC connectors.
The unit was intended as a quad splitter for multiple cameras or VCRs, back in the analog days of surveillance video equipment, and comes defaulted to showing 4 split screens.
To use it as a TBC for video capture:
- Connect two BNC>composite adapters to "input 4" and "monitor.
- "Monitor" is essentially video/VCR out.
- Both "input 4" and "output 4" are identical in monitor mode, and both show the VCR signal. "Output" may have less noise than "input", or vice versa. Swap as needed.
- If noise is detected from both input/output on 4, swap to 1.
- When turned on, it defaults to the 4-camera split screen.
- Press 4, and you should now see your incoming VCR signal. If
The buzzer and on-screen (display) text can be disabled in the menu. MENU enters, UP/DOWN to navigate, ENTER to enter a menu item, MENU to exit menu item, MENU again to fully exit. The unit has lots of options, and if you hit the wrong button, it may enter another mode. If you get lost, refer to the manual.
Wrong connection of the unit can result in bypassing the TBC chips, or entering a noisy mode. Do not use VCR IN and VCR OUT, that does not work correct!y
Unlike TBC-only units from Cypress, the video values of the quad splitters don't seem to be calibrated, and can vary quite a bit from unit to unit. On the CAMERA menu page go to channel 4 (aka input 4), and alter image brightness and contrast as needed. The AVT-8120 units tend to be a bit bright, needing anywhere from -1 to -8 to look accurate. Contrast can remain at 0, though sometimes need a +1 or +2 tweak. That means that the AVT-8120 has a defacto proc amp, much like the 1T-TBC and AVT-8710 TBCs.
All TBCs add some degree of processing noise. The goal is to get a unit with the most transparency. The AVT-8120 has a very clean image, but is not flawless. It has a tiny mouse cursor in the upper left overscan, as it was an item connected to a larger surveillance system via RS232. However, this should not be an issue, as overscan imperfections/noises should be masked post-capture anyway.
It uses a Jentec AC adapter, model AH1812-B, 12 volt 1.5 amp (12V 1.5A), center positive polarity. The Phihong PSM11R-120, 12 volt 840 milliamp (12V 0.84A), center positive, is an acceptable replacement adapter known to work.
By default, DIP 1 is on, 2-4 are off. However, tvONE has stated (to me) that the external DIP switches are completely inert. On most units, on/off doesn't seem to change anything, so that seems accurate. However, on other units, it's also been observe to change black level and/or luma.
It's well known that JVC S-VHS VCR menu screens are not 100% NTSC compliant, and it can sometimes cause problems with other gear in a workflow. For example, it makes a known-bad AVT-8710 act worse.
And it's worse with composite output than s-video. The AVT-8120 can have various minor noise patterns from a JVC menu. It you see these, don't freak out. The input and output of the unit is probably fine. Notice that the split-screen blue screen generated by the unit is clean, and the VCR tape when played is clean. It's just the menu. The menu-caused noise will not be seen with a DMR-ES10 or ES15 between the JVC and AVT-8120, as the ES10/15 units output a cleaned signal. However, this is not a TBC(ish) setup that requires the ES10/15, and an ES10/15 is just optional for anti-tearing usage.
This excludes power-related noise, which should not be ignored, and would be visible on input, output, or both.
Because it's essentially a composite-only AVT-8710, this also means it can suffer the same fatal flaws as the black AVT-8710 and latter 1T-TBC/1T-TBC-GL units.
So beware of buying any ol' AVT-8120, you must verify the serial numbers. Unlike the 8710 and 1T, it's not as easy as verifying date codes. The serials 22384030048xx and 22384030055xx are known to be good units, likely being in the first batch of new-style serial codes. Anything beyond those first 5600 units is unverified. Please Contact Us to add known good or bad serials. And the later the Cypress, the worse it is.