Equipment to delay a RS422 connection

Where can I find a piece of equipment that can delay a RS422 connection? Ideally the delay should only work one way i.e. the Tx should be delayed and the Rx should not be delayed. The delay should be adjustable in the range 0-40 ms.

Thanks for any help.

Peter

Reply to
Peter Thomsen
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Hmmm.. Me puzzled. Why???????

Reply to
Alan N

Indeed. Setting the bitrate to 200bits/sec will give you a 40ms delay for 8 bit characters. Higher bitrates will reduce this proportionally. Of course, this will vary the throughput as well as the transit delay, but without any clue why you want to do this, I've no idea if that matters.

Reply to
Andrew Gabriel

Yes, I know it is a rather strange requirement.

The matter is to align the command sent to a video switcher, with the play command send to a video server. This to make sure that the On-air transition from one programme to the next takes place without spurious pictures of one video frame.

What I forgot to mention is that bit rate is 19.2 kbit/s or 38.4 kbit/s

Still hoping for useful hints. Peter

Reply to
Peter Thomsen

I recall that circuit designers sometimes use a long piece of wire to delay a signal a specific amount of time.

I don't recall the formula, but I wonder how long the wire would need to be to delay the signal 40ms. I know that electricity travels through wires much slower than the speed of light, but I still suspect it may be too long. ;)

-Z

Reply to
Zorin the Lynx

Sometimes. I've seen memory made out of long hunks of coax cable. Launch a serial string at one end wait for it to come out the other and re-launch it. When the data of interest comes around take it or update the string.

Most wire is about 50% slower than light or about 1.5ns per foot. Your

40ms wire would be ~5000 miles long. ;-)
Reply to
Keith R. Williams

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