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GV-250-2,#2 cam image dims/fluctuates like slow heartbeat

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Hi, I wonder if my problem is easy to solve.

The 2nd camera image on my GV-250 fluctuates (brightness dims) like a slow heartbeat triggering motion recording. I've gone into advanced motion setup and set both cams to record at 8 fps so as not to exceed the total 20fps that this entry-level Geo card offers. At one point I had selected "auto" for fps assignment to the motion-active cams and the images on both cams went haywire with the color becoming grossly exaggerated while getting brighter and dimmer over a 5-10 second-or-so period.


Thanks to anyone who can point me to an obvious solution. I'm new to this, did a search here to find a solution but don't know what to search for.


My system:

D915GAG Intel mobo, 3.0 GHz P4, 1GB RAM, onboard video, XP ProSP2

Enermax 350 Watt p.s. old 80GB Maxtor HD

GV-250 2port DVR card using V8.2 s/w (verified genuine by Geovision)

Cam 1: KTC KPC-VBN195 (worked perfectly alone through 30 ft Cat5 cable with Chinese baluns)

Cam 2: KTC KPC-DNR700 (on 2 ft RG-6 patch cord to DVR card)


Settings in Geo 8.2:

640x480 deinterlaced, tried various fps record limits to correct,auto fps, no avail.


p.s. I just swapped Cam 2 for a BW KPC-S400 no change in settings: Cam 1 color went very bright and quality dropped. New Cam 2 view started pulsating...muhaha!!

It's driving me crazy!

Okay, I just unpowered Cam 1 and the other one's brightness is now outta control, going dim and super bright....why??? (Does not matter which Cam is #2, they all bloom and dim)


Thank to any saviours here.


Update: I did not mention that Cam 1's signal was split through a BNC T-fitting (the view on geovision screen and other view on remote TV was perfect) but Cam 2's view only became rock-solid when the the T from Cam 1 was removed. Ya would think that splitting the signal would mess up that port, but oddly the other port was.

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Sometimes when I experience a view like that it depends on the monitor. Some views of mine do that on my cheap HD tv, but not on regular old monitors.


Also, most of the time when I have used a T splitter the signal does get degraded pretty bad. To solve this I've used a distribution amplifier that has 2-4 outputs so you can run the signal to multiple monitors/recording devices. A quick search online should help you find one that is cheap enough.


Are each of the cameras sharing a power supply port? I also assume that you are using the correct voltage power source for them (not putting a 12V camera on a 24V power supply). In my system I had a camera acting poorly like yours and found out it was a 12V camera on my 24V power system.

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T connector could be getting some ground coming from the TV.

If Cable TV is also connected to the TV remove that and see what happens - that was the cause of lines on one TV I had a DVR plugged into, could present other issues. Could just be a cheap or bad T connector also.


And the fluctuating light, if that is indoors its likely the type of lighting, happens with some cameras.

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Thanks for the replies. Disconnecting the split signal at the 46" Dynex (Best Buy brand) TV is what cures the image problem on the other port.

As I had mentioned from the start, the split signal is fine in both views, it's the other port with the un-split signal that gets messed up. Both cams are on their own class 2 ps, but, as Rory had suggested, there may be some ground issue involving the TV.

I'll look for a splitter/amp to do it the right way. I'm getting a GV-800 (genuine?) today and will swap to see if the problem resurfaces.

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Okay, I just replaced the GV250 with my newly acquired used GV800 V3.51 running on V8.5 and the problem is gone. So whatever ground issue from the TV there was, the newer card and/or later software are not affected. (It took me hours to make an 8 cam, 4 audio cable for the GV800 that came with no wiring.)

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