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Multiplexer Question

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Fella's

 

I have several used multiplexers and I even utilize one in my current 16 camera system that I have which is also hooked up to a Samsung Time Lapse VCR. I know just a few years back that this was the standard way of doing things before DVR's became prevalent and I am sure there are still quite a few people doing this.

 

There are alot of advanced features on my multiplexer such as motion detection that will trigger my VCR on. Alot of these advanced features I have not even delve into yet but I am on a quest to educate myself more about my products. What I do now with my current setup is I record 24/7 set at 240 hour mode on my VCR. During the day, I just set the multiplexer to switching mode and it will record all 16 of my cameras which switch every 3 seconds. At night, I set my view at 4 camera view for my four most important cameras and just record that way. I could set my multi to 16 camera view but the boxes are so darn small that you can hardly make out anything, plus the frames per second is pretty low when I do that and then when you run it through a time lapse VCR it makes it even slower. My Multiplexer does have an option to digitally zoom in on a square during VCR playback but everyone knows how crappy digital zoom can look. I could set my multiplexer to motion detection mode but what if I have motion going on 8 or more cameras at the same time. I feel like I am losing the opportunity to record all 16 cameras. My question is, is there a major feature or function that I am possibly missing out on? Or how is the best possible way to get 16 cameras recorded with a 16 channel multiplexer and one VCR? Or is this just the major limitation of a VCR system? I am open to any and all suggestions and counter-questions.

 

A little bit about me: I just happen to run across the opportunity to sell these products just about a year ago and I have become fascinated with this industry and thoroughly enjoy doing this. I have learned quite a bit about this stuff within the past year but I still want to learn more and become as educated as possible. I can usually help my customers with the basic hookups on my products but every now and then I get a question that stumps me about an advanced feature so that is why I am here. Quite often, my customers are installers and are way more educated than I am on my products but its the do-it-yourself homeowners who I really need to reach out to. We all start somewhere right?

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You should be using a time lapse VCR or Single Channel DVR that can demux the particular brand of Multiplexer you have. That way you can be recording all cameras at once and play back each one individually. Its been a while but I believe there should be a VCR out on the multiplexer which should be the muxed video.

 

It sounds like you are just using the video out from the Multiplexer to the VCR and only recording what is on screen?

 

Its alot cheaper though to just buy a stand alone DVR one time ... we stopped using muxes and VCRs and single channel DVRs several years ago.

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Yes you are correct. I am simply recording what is on the screen via the video out.

 

Their is a "VCR out" on the multiplexer, although I thought it was just for when you can play back the video and use it to digitally zoom in on a box when the tape was recorded in 16 camera view. I will have to mess around with them both to see what I can find out as far a muxing and demuxing. I have the manuals but they really arent very descriptive when it comes to stuff like this. I am sure that the recorder I have will be able to demux the video as both the multiplexer and VCR came from the same retailers security system. Will post questions along the way. But here is one to begin with, please tell me what the "triplex" term means in layman.

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Triplex: view live, playback, and record at the same time.

I dont think the triplex works with VCR though, only DVRs.

As I said, its been several years its like asking me about Windows 95 now ..

With stand alone all in one DVRs the terminology or technology has all changed and it can differ so much from one manufacturer to the next.

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Okay I gotcha. According to the manual, I think these multiplexers can do a triplex operation but in order to record and play at the same time you have to have 2 VCR's in the system. One for recording, one for playback.

 

You have to admit though, windows 95 was the best version! LOL.

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LOL right thats what it was .. 2 VCRs ... i tell you so much has happened since then i just couldnt remember

 

yup 95 or nuttin

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I'm with Rory, your best bet is to insert the VCR into the VCR loop on the MUX. Some MUXes need to be configured for the specific VCR being used, but if they're the same brand, it may "just work". Can't hurt to try, anyway.

 

If you're familiar with how VCRs record, this will give you a clue as to how it interacts with the MUX. Hooking a monitor to the VCR OUT jack will give you an idea as well - essentially the MUX just flips from one camera to the next, in sync with the VCR recording video frames, so in essence, each frame is one camera. On playback, it then reads each frame back and sorts each camera to its appropriate channel.

 

The upside is that each camera is in full res... the downside is that each camera is recorded only every 16th frame, or only a couple of times per second.

 

That's a little over-simplified, but hopefully it helps...

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To elaborate on Soundy's comment, most multiplexers either had menu settings to allow matching the recorder(and recording speed) to the rate of images coming out of the multiplexer, or (ideally) a synchronization connector that allowed the recorder to trigger the change of images from the multiplexer.

 

That way, each single image recorded would be matched to a single image from the multiplexer, for the most efficient recording. That also allowed for changing speeds on the recorder, and still have matching frame rates sent from the multiplexer.

 

Your best bet for a decent recording rate is to use a "real time" 24 (40, on a few)hour recording mode, that gives you 20 frames per second recording/16 cameras= a little over one frame per second, per camera. At the 240 hour speed, I think you only get about 2-4 frames per second, that divided by 16 cameras equals a pretty low frame rate.

 

Another feature of multiplexers that could be implemented is that some had motion detection features, to allow recording more frames per camera for ones that had active motion than ones with no motion. Also, recorders often had an "alarm" hardwired input to allow changing to higher recording speeds in the event of a holdup, etc.

 

Us old-timers will gladly wax poetic about the features of Robot, American Dynamic, and Pelco muxes, as well as the durability of the Panasonic AG-RT600 half width recorder for as long as you'd like (or as long as we can still remember ).

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Us old-timers will gladly wax poetic about the features of Robot, American Dynamic, and Pelco muxes, as well as the durability of the Panasonic AG-RT600 half width recorder for as long as you'd like (or as long as we can still remember ).

Hmm, that must be a similar unit to the TLS-4072 - I think of the few VCRs we still have in service, most are those model.

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Us old-timers will gladly wax poetic about the features of Robot, American Dynamic, and Pelco muxes, as well as the durability of the Panasonic AG-RT600 half width recorder for as long as you'd like (or as long as we can still remember ).

Hmm, that must be a similar unit to the TLS-4072 - I think of the few VCRs we still have in service, most are those model.

 

Yes, the AG-RT600 was an older model of the same style....A real workhorse, saw a lot of use in casinos.

 

Had a setup that had a Genex multiplexer, THREE recorders, (one daisy-chained to the next for extended recording, and the third for playback, a Pelco 6700 matrix with three original Spectras and ten other fixed cameras, about twelve Optex wireless units to call PTZ presets through alarm inputs on the matrix, and a Prism MicroMole300 phoneline video transmitter for off-site viewing to Windows 95 based receiver, in a high end residence. That was a hot setup around '97 or so.....

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All the multiplexers are either GVI or Ultraks. My main recorder is a samsung but also have some GVI's and Ultrak's as well.

 

There was actually a tape inside one of the VCR's that I got from this retailer and I played it and as you said, it looked like a bunch of cameras switched rapidly. It obviously needs to be de-muxed.

 

I have to sit down with a cup of coffee or 2 and try to get it figured out one morning.

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Basic setup is usually pretty easy, there is a VCR input on the mux that goes to the VCR output, and vice versa, and a monitor output on the mux that goes to the monitor. You will need to find a "live/playback" button, and select playback, to view the tape output.

 

The camera selection buttons on the mux should bring up the associated camera view for an individual view, and the split screen buttons, as well.

 

If you look at a frozen frame of that recorded video, without playing through the mux, you will see something that looks like a barcode at the (usually) very top of the image. This is added by the mux to each image during recording, and is how the mux identifies each individual camera to place back in the correct position for viewing.

 

High end forensic video software can decode this barcode also, so police departments do not need an assortment of multiplexers to view video taken from different sites.

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a Prism MicroMole300 phoneline video transmitter

 

Wow! Haven't heard that name in a while! I'm impressed, old timer.

 

We actually still used that crap until about 5-6 years ago when we switched to DVRs. Micromoles and NIUs... what a PITA to get to work and keep working.

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a Prism MicroMole300 phoneline video transmitter

 

Wow! Haven't heard that name in a while! I'm impressed, old timer.

 

We actually still used that crap until about 5-6 years ago when we switched to DVRs. Micromoles and NIUs... what a PITA to get to work and keep working.

 

....If you ever built your own DVR's with Win98, the Prism units didn't seem so bad. Newer DVR users probably wonder what the daily reboot option is for

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I finally had time to mess around with this and got it set up to mux and demux. The demuxing was done through the multiplexer. Pretty amazing I thought. The only thing I didnt like about it was the fact that when I had the multiplexer set at 16 camera recording, you get the "lapsed" video effect, and then combine that with a time lapse recorder, the lapse gets multiplied depending on what time lapse mode you have it set at. But I figure I would set it up at a lot lower time lapse and configure the motion detection on the multiplexer to get some better video quality. Pretty sweet stuff though.

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Okay fella's I want to get my multiplexer to trigger on my VCR for motion detection and Macro recording. There are inputs on both the multiplexer and VCR for Alarm in and Alarm Out. My questions is, do I just use a typical power wire to connect these 2 devices? Such as a snippet of wire off of my siamese cable? Please confirm.

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Yes, pretty much any wire would work. Make sure you connect the ground wire between the VCR and mux, as well as the alarm trigger wire.

 

Typically, wire from the alarm out terminal from the mux to alarm in on the VCR, as well as the ground, is what's required.

 

Take a look for a synchronization (or similarly titled connector) between the mux and VCR, as well, with this connected it makes sure that one frame of video recorded on the VCR matches up with a single frame of video from the mux, no matter what speed the VCR is set to (you do usually have to enable this in the mux settings).

 

That will improve recording performance by a fair amount.

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