Chaining VCRs to make multiple copies

[jtaylor]

If I run video to one vcr, and video from that to another, etcetera, how
many "links" in the chain will result in

a) a noticeable degradation
b) an unwatchable picture

I suppose that it rather depends on the VCR's involved.

I don't know whether the video out is just wired straight to the input, or
it goes through some electronics first - is there a standard method?

A number of "links <5 for situation a) above might be ok for our purposes...

 

[Neil]

It will degrade pretty fast with your "Daisy Chain" method, probably after
the second VCR.
Usually each VCR is fed from a DA (Distribution Amplifier). The signal is
split, and is amplified by the DA. This makes certain that the input to each
VCR is good quality. You can usually find user DA's with 10 or so outputs
fairly easily.
Kim

 

[Glenn Gundlach]

If I run video to one vcr, and video from that to another, etcetera, how
many "links" in the chain will result in

a) a noticeable degradation
b) an unwatchable picture

I suppose that it rather depends on the VCR's involved.

I don't know whether the video out is just wired straight to the input, or
it goes through some electronics first - is there a standard method?

A number of "links <5 for situation a) above might be ok for our purposes...

The gadget you want for video is called a Distribution Amplifier (
'DA' ). For small numbers of VCRs, it is probably OK to 'y' cord the
audio but not for the video. You're right about the video
deteriorating going through the VCRs in E-E mode. E-E is 'Electronics
to Electronics' and likely originated with Ampex and the first VTRs
(Video Tape Recorder). Elantec, Burr-Brown, National Semi, Analog
Devices (and others) make opamps suitable for DAs. eBay may have used
broadcast DAs which would do just fine.
GG

 

[Philip A. Marshall]

If I run video to one vcr, and video from that to another, etcetera, how
many "links" in the chain will result in

a) a noticeable degradation
b) an unwatchable picture

I suppose that it rather depends on the VCR's involved.

I don't know whether the video out is just wired straight to the input, or
it goes through some electronics first - is there a standard method?

A number of "links <5 for situation a) above might be ok for our purposes...

Maybe grab a handful of cheap op-amps and use some simple voltage
followers to buffer the output... Quick and dirty. Probably not
perfect, but better than a daisy-chain method. And at unity gain, it
should be fairly easy to find op-amps that meet the bandwidth
requirements more or less.

 

[David L. Jones]

If I run video to one vcr, and video from that to another, etcetera, how
many "links" in the chain will result in

a) a noticeable degradation
b) an unwatchable picture

I suppose that it rather depends on the VCR's involved.

I don't know whether the video out is just wired straight to the input, or
it goes through some electronics first - is there a standard method?

A number of "links <5 for situation a) above might be ok for our purposes...

Use a video distribution amplifer (1 input, N outputs) to drive as
many VCRs as you want from the one source. Don't daisychain.

Dave