TVI Camera Shows No Picture on the DVR? Fix the Signal Type

12 min read · Oct 20, 2026

When a tvi camera shows "No Video", a rolling picture or a black and white image on a recorder, the most common cause is that the camera and the DVR are not speaking the same signal format. Analog HD cameras can send TVI, AHD, CVI or plain analog (CVBS) over the same coax cable, and a DVR channel set to the wrong one cannot decode the picture. The fix is to make both ends match: switch the camera's output format, or set the DVR channel to the right type or to Auto. Only after that should you look at cables, power and the camera itself.

This article is about cameras that connect to a recorder with a coax (BNC) cable. If your camera connects with a network cable or over Wi-Fi, it is an IP camera, and the checks are different — see the PoE camera setup guide instead.

First, know what kind of camera you have

The labels on the box, on the camera's cable tail, or in the listing often read like a list of letters — something like "HD camera AHD IP TVI DIS" on a shop sign — and it helps to know what each one means:

TVI, AHD and CVI are three different analog HD formats. They all use coax and BNC plugs, they look identical from the outside, but each encodes the picture differently.
CVBS (sometimes labelled CVBS, analog or "960H") is the older standard-definition analog signal. Most DVRs with BNC inputs can display it, but check your recorder's specification.
IP means a network camera. It does not connect to a BNC input at all; it needs a network cable or Wi-Fi and an NVR or an app.

Many analog cameras sold today, including the typical analog dome camera and small bullet cameras, are "multi-format" models that can output more than one of these signals. They usually leave the factory set to one format, and that default may not be the one your recorder expects. Check the label on the camera or the cable tail, and the manual for your model, to see which formats it supports and how to switch between them.

Read the symptom on the screen

What you see on the DVR monitor tells you a lot about where the problem is:

"No Video", "Video Loss" or a blank channel tile. The DVR is getting no usable signal. This can be a format mismatch, but it is also what a broken cable, a dead power supply or a wrong channel looks like.
A picture that rolls, scrolls, shakes, or is split into bars or repeated strips. The DVR is receiving a signal but decoding it with the wrong format or the wrong frame setting. This is almost always fixable in settings.
A black and white picture during the day. Either the DVR is reading the camera as plain analog and losing the colour information, or the camera's video system (PAL or NTSC) does not match the recorder. It can also simply be night mode stuck on — see the note below.
A stretched, squashed or cropped image. The DVR channel is set to a different resolution or format than the camera is sending.
A picture that appears, then drops out. This points more towards power or a loose connector than format.

A quick note on black and white: if the image is grey and the infrared lights are glowing even in daylight, the camera may be stuck in night mode, which is a different problem. The checks in the night vision troubleshooting guide cover that case.

Step 1: Check the DVR channel input setting

Start at the recorder, because you can change it from the sofa with a mouse.

Open the DVR's main menu and look for a section with a name like Camera, Channel, Analog, Signal Type or Channel Mode. Names differ between recorders and firmware versions.
Find the channel the camera is plugged into. You will usually see a setting for the input type, with choices such as Auto, TVI, AHD, CVI and CVBS.
If it is on a fixed format, try Auto first and save. Give the DVR a moment to detect the signal.
If Auto does not lock on, set the format manually to the one printed on the camera label, save, and wait again.
If the channel still shows nothing, try each available format in turn.

Some recorders also have a resolution or frame rate option per channel. If the format looks right but the picture is still stretched or flickering, set these to Auto or to the values listed for your camera model.

Hybrid recorders can take both analog and IP cameras, and on some models certain channels can be switched between "analog" and "IP" mode. If a channel has been switched to IP mode, a coax camera plugged into it will show nothing, however the format is set. Check that the channel is in analog mode.

Finally, check the DVR's manual or specification sheet for which formats and resolutions it can decode. An older recorder may not support a newer camera's format or its higher resolutions at all. In that case no setting on the DVR will help; the camera must be switched to a format the DVR can read.

Step 2: Switch the camera's output format

If the DVR cannot be set to match, change the camera instead. Multi-format analog cameras usually offer one or more of these methods; check the manual for your model, because the exact method varies.

The control on the cable tail. Many cameras have a small joystick or a few buttons on a short lead coming out of the cable. On a lot of models, holding the joystick in one direction for several seconds cycles the output format, and holding it in another direction cycles back. The manual tells you which direction selects which format. Change it one step at a time and watch the DVR screen: the picture usually goes blank for a moment, then returns in the new format.

A small switch on the cable or inside the housing. Some cameras use a slide switch or DIP switch instead of a joystick. Switch off power before changing it, set it to the format you want, then power up again.

Coaxial control from the DVR. Some recorders can send menu commands up the coax cable to the camera. In the DVR's live view, right-click the channel and look for an option such as PTZ, Coaxial Control or Camera Menu. If the camera responds, its on-screen menu appears over the picture, and you may find the output format option there. This only works when both sides support it.

PAL or NTSC. In the same camera menu, or on the joystick, there is often a video system option. Set it to match the DVR (the DVR's own setting is usually in its system or display menu). A mismatch here is a classic cause of a rolling image or a picture with no colour.

Once you find the combination that gives a stable, coloured picture, write it down or put a small label on the camera's cable tail.

Step 3: Rule out the cable and connectors

If no combination of settings gives you a picture, the signal may not be reaching the DVR at all. Before you do anything up a ladder, switch off the power to the camera and use a qualified electrician if any mains wiring is involved.

Swap the camera to a channel you know works. Unplug a working camera's BNC at the DVR and plug the problem camera into that input. If the problem camera now works, the original DVR input or its setting is the issue. If it still shows nothing, the problem travels with the camera or its cable.
Inspect the BNC plugs. A loose centre pin, a crushed plug or a connector that spins freely without locking is a common cause of no video. Re-terminate any plug that looks doubtful.
Check for corrosion and water. Outdoor joints that were not sealed can corrode and kill the signal, especially after rain.
Check the cable run. Very long runs, cheap cable with thin cores, or sharp kinks can weaken the signal until the DVR loses it. The safe distance depends on the format, the cable and the camera — check your camera's manual rather than assuming.
Baluns. If the system uses network cable with video baluns instead of coax, make sure the baluns are rated for HD analog signals and that both ends use the same wire pair. Older baluns made for standard-definition video can cause a rolling or noisy HD picture.

The best single test is to carry the camera to the recorder and connect it with a short known-good cable and its own power adapter. If it works on the bench, the problem is in the cable run, not the camera or the format.

Step 4: Check power to the camera

A camera that is not getting enough power can produce no picture, a flickering picture, or a picture that works in daylight and drops out at night when the infrared lights switch on.

Check that the power adapter matches the voltage and polarity printed on the camera label. An adapter that fits the plug is not proof that it is the right one.
If several cameras share one power box, check whether it can supply all of them, including the extra load of infrared at night.
Look at the power connection at the camera end for loose or corroded joints.

If you are unsure about anything involving the power supply or mains wiring, switch off at the source and ask a qualified electrician.

Step 5: Narrow it down to the camera or the DVR

After the steps above, you can usually decide which part is at fault:

Camera works on a different DVR channel, but not on its own channel: the original input is faulty or its setting is wrong.
Camera does not work on any channel, even on a short bench cable with a good adapter, in any format: the camera is likely faulty.
Other cameras also show no video on the same DVR: check the DVR itself — firmware, the overall channel mode, and whether it can decode those formats at all.
Camera works on the bench but not when mounted: the cable run, joints or power at the mounting point are the problem.

For problems that are not about signal format at all — a camera that is offline in the app, a recorder with no playback, or a whole system that stopped after a power cut — the step-by-step security camera troubleshooting guide sorts symptoms by layer. If your cameras are network cameras viewed in an app and the live view is black even though the camera is online, see how to fix a black live view on a CCTV camera.

When to get help

Ask the seller or an installer for help when:

You have tried every format and video system setting on both the camera and the DVR and there is still no picture.
The camera does not work on a short bench test with a known-good cable and adapter.
Fixing the problem means working at height, on a roof, or with mains wiring. Switch off the power first and use a qualified electrician for anything electrical.
You are not sure whether your DVR can decode the camera's format at all. The seller can confirm compatibility for the exact models you have.

When you contact them, have both model numbers, the format on the camera label and a photo of the DVR screen ready.

Install or resell cameras?

A "no video cctv" call-back on an analog job is often a format or video-system mismatch that could have been caught before leaving site:

Check the DVR's supported formats before you order cameras, especially when adding cameras to an older recorder you did not install.
Set every camera to the same format on the bench, then set the DVR channels to that format or to Auto, and confirm each channel shows a stable colour picture.
Match PAL or NTSC across the whole system and note it on the job sheet.
Label each cable tail with its format and channel number, so the next technician does not have to guess.
Test at night as well as in daylight, because a weak power supply often only shows up once the infrared switches on.

If you install or sell cameras for customers, details of the Yoosee dealer program are at business.yoosee.com.

Frequently asked questions

Can I connect a TVI camera to an AHD DVR?

Only if one of them can switch to the other's format. Many multi-format cameras can output AHD as well as TVI, and many recorders accept several analog HD formats, so check the camera label and the DVR's specification. If neither side supports a shared format, you will not get a usable picture, even though the plugs fit.

Why does my camera picture keep rolling on the DVR?

A rolling or scrolling image usually means the DVR is decoding the signal with the wrong format, or the camera and the DVR are set to different video systems (PAL and NTSC). Set the DVR channel to Auto or to the camera's format, and make the video system match on both sides. If it still rolls, check for an old video balun or a damaged cable.

Why is my new camera only showing black and white on the DVR?

During the day, a black and white image often means the DVR is reading the camera as plain analog, or the PAL and NTSC settings do not match. Change the camera's output to the analog HD format the DVR supports and match the video system. If the infrared lights are glowing in daylight, the camera may instead be stuck in night mode.

Can I plug an IP camera into a DVR's BNC input?

No. An IP camera sends video over a network cable or Wi-Fi, not over coax, so a BNC input cannot read it. You need an NVR, a hybrid recorder with IP channels, or an app that supports your camera. Some hybrid DVRs can add IP cameras over the network, but that depends on the recorder and the camera.

Will changing the camera's output format damage it?

Switching formats with the joystick or the camera menu is a normal, reversible setting change, not a hardware modification. If your model uses a physical switch inside the housing, turn the power off before changing it. If you cannot get the picture back afterwards, the manual usually explains how to return the camera to its default format.