Hi all,

Im new here but have been reading with great interest as I figured out the bits needed for my first CCTV project!

I have my DVR setup and working perfectly. However, I also wanted to hookup a QUAD processor in addition to the DVR and have the outputs from this going to a different monitor.

I purchased a quad processor online, but as soon as I connect the loop BNC's on the back of the DVR to the QUAD, I get very serious picture quality issues on both the DVR and the QUAD. The pictures start to jump and flicker and some of the cameras report VLOSS.

The DVR is an AVR505 and the QUAD is a generic brand.

If I unplug the loop wires from the DVR, the DVR and its cameras come back to normal.

What am I doing wrong? Any help appreciated!

Thanks,
Jab

Probably some sync issue with the quad, try plugging them into the quad only, see how that is, ive had 2 cheap quads do this to me installed by themselves, just resetting the power a couple times did the trick.

If the quad works by itself, and you go back into the DVR with the quad, and its still doing it, then I guess they wont work together, perhaps contact the quad reseller and see what they have to say. Maybe go through the quad first then to the DVR and see if that fixes it also.

Check the termination settings on the DVR and the Quad. When looping video to another device, the last device in a chain should be terminated and the rest should be unterminated.

Yup,Sounds like termination problems, the multiplexer (and quad maybe) should have some option to set/unset the 75ohm terminator for each camera (unless its done automatically).Check the manual for both devices.

Hi Guys,

I will try those suggestions later. I think it could indeed be termination. There is a jumper on the back of the DVR to switch "high impedenece" on/off. However I suspect that the Quad doesnt terminate (may be the problem?).

If that was the case, would things work ok if I was to tee off the cameras before the DVR and have one side of the Y into the DVR and the other into the quad and therefore not use the loop on the DVR at all?

Any suggestions welcome.

Thanks,
Jab

Whats the dvr termination currently set to? Its possible your getting double termination, ie both the quad and the dvr are terminating. Test by turning of termination at the dvr,see what happens.

Hi,

Will check later this evening and report back. The link below shows the quad item that I bought, I suspect that taking the cheap option may be the cause of my problems!

I dont think it has an option to terminate / not!

Cheers,
Jab

Doh...cant post a U-R-L, its on eBay auction ID 330114196846, just go to eBay and enter this ID into the search box!

I would guess that that will be terminating as it would have to for people who just have cams and the quad. So if the dvr is terminating also, its got 150 ohms total, not 75. Turn of termination at dvr, leaving the quad to terminate, and hopefully that should sort it.

termination should cause bright video, never seen lines from it.

Hi All,

Bad news im afraid....

I tried plugging the cameras directly into the quad and it worked fine. Then tried using the DVR looped to the quad (as before) and the result was that some of the cameras had video loss, some got all fuzzy/jumpy.

When tried switching to "high impedance" on the DVR (dip switches on the back) and then all of the cameras turned to either white screen or video loss?!?!?!

Any suggestions? This is a little baffling!

Thanks,
Jab

I would could a video splitter. I could find a splitter and post it here so you can see if this is something you can use.

Camera #1 Input to video splitter. Output A to DVR, Output B to Quad
Camera #2 Input to video splitter. Output A to DVR, Output B to Quad
ECT.
ECT.

Is this a viable option?

Hi, this is certainly an option. Is there a particular type of splitter or would just a regular coax/satelite splitter do?

Tx,
Jab

Actually, that would be 37.5 ohms total. Two equal value resistors in parallel equals 1/2 the resistance, not double.

You can't just split video signals. You have to use a Distribution Amp.

A distribution amp?....where would one acquire one of these! (or in my case, several of these!). Not looking to break the bank here, so budget on-line options welcomed!!!

Thanks,
Jab

They are available at many stores and distributors:
Radio Shack - http://www.radioshack.com/product/index.jsp?productId=2103065&cp=&pg=2&sr=1&origkw=video+splitter&kw=video+splitter&parentPage=search
ARM Electronics (many places) - [edit by mod - link removed]

Do a web search for video distribution amp(lifier).

Hey Jabaroon,

Did you get your system up and running?

Hi Scorpion,
No, I havent yet managed to get a distribution amp im afraid!

Jab

I look forward to finding out the outcome. Keep me posted!