#Video "NOISE"#$!?@!
16 messages in this thread
I've got problems with signal interferance on my Toaster/KitchenSync/
AG1970 edit system. I get "noise" on my video appearing in the form
of irregular horizontal and vertical bars. I recently purchased
about 400.00 worth of Canare top grade cables from MarkerTech, so I
know my cables aren't the problem. BTW all the cables are 6 Feet, no
adaptors and sheilded. I have attempted to separate my Video cables
from my A/C cables as much as possible by running all AC connections
down on floor level, and keeping my Video cables tied and suspended
at Desk level, therefore I have no paralell running only the
inevitable crossings. I'm wondering if I'm getting RF from my 1084S'?
By running the video at desk level they are in close proximity to
these monitors. Any suggestions on shielding my video cables
further? What material should be used for this if it is a valid
option? Any info or other experiences dealing with eliminating video
NOISE would be appreciated.
Quite possibly a lot of your video noise is due to a design flaw
within the Kitchen Sync. I posted a note about some noise with my
system a few days ago, and very quickly had 2 or 3 responses from
other KS owners describing the same or similar noise problems. I
think we should start voicing our opinion to the manufacturer…
Maybe you guys should also call the Digital Creation BBS and leave a note
there too. At least others that may be interested in a Kitchen Sync will
be aware of what is going on.
Digital Creations BBS: 1-916-983-3288
<<< Tony D. Tracer >>>
(Any render time >0 needs acceleration.)
Tony D.,
Thanks for posting that BBS #. I'll indeed post a note on it today!
Jerry
A lot of your problem is coming from the Kitchen Synch. It is a bad TBC,
that's why it's so cheap. Bump yourself up a notch in TBC quality and you
will be pleased with the results.
Here's the kicker, make absolutely sure you don't have cable (the service)
hooked up to any monitors or VCRs. This is the vertical lines, TBCs are
the horizontal lines.
Hey, I do have a cable feed into my VTR!! I definately will disable that
before my next editing session.
Thanks, Jim
I disconnected all cable feeds into my system; noise still there…
🙁
My next potential solution, I've just ordered several TripLite Isobar
surge protectors. What looks different to me on these is that it not
only protects the equipment from Line noise and surges coming
in…but it isolates and prevents noise from the individual
circuits. I do believe that I've got noise going between circuits on
the equipment side of my surge protectors. Any other experience with
defeating video 'noise'? I'm still not totally convinced that my
Kitchen Synce is the culprit here, but I am preparing the budget to
acquire a couple a DPS TBC IV's. If the KS is the problem, is it
possible that only some are deficient or is it a design defect? Does
anyone have a Kitchen Sync that supplies a totally clean signal?
Later, Jim
I almost ordered 2 TBC IV's today, but decided to wait on reponses
from a couple of e-mails I sent asking about the performance of the
IV's before I shell out hard earned bucks on them like I did the
Kitchen Sync. I'm _convinced_ that the problem is in the Kitchen
Sync, _and_ that it's just the way they are, i.e. design flaw. I've
changed cables, added electrical surge protectors and noise isolation
protectors. I've adjusted the Toaster via its software setup panel.
I've isolated the trouble in my particular system, and it's in the
KS. However, if you discover something different, _please_ let me
know!
Jerry, have you looked for a ground loop anywhere yet? I've had terrible
problems with them in the past before I took everything to a common ground buss
which was totally independent of the mains provided ground.
Vince
Vince,
I've isolated grounds, connected grounds, turned off pieces of
equipment one by one, disconnected them completely, virtually
everything I could think of, _except_ actually creating a 'network'
to ground everything to one wire, and then running it outside to a
ground rod. Heck, I'll even try that. However, remember that my
problem is definitely tied to the Kitchen Sync; i.e. the noise is
not there when coming directly from source decks to monitors, nor is
it there when feeding a camera signal directly through the Toaster
without the Kitchen Sync. But, when I route the same camera signal
through the Kitchen Sync, it _is_ there. I called my distributor
today to order 2 TBC IV's, and they were out of stock…:(
Thanks,
Jerry
Jerry, try this one for giggles; The TBC has a three pin grounded plug feeding
the power supply, right? If so, stick a "cheater" on it to lift that pin from
the mains ground and try putting it in the loop. I have piece of Panasonic
trash that I have to do that with just to be able to use it as a source deck.
There is something screwy within the power supply that I've yet to find that is
injecting 25 kc garbage back into the signal ground with that ground pin
connected, but not when isolated. Just left the cheater on and ran a piece of
#12 solid to the frame ground and it works fine, but I be darned if I can
figure out why it is this way. Spent about two months in the service manual
and schematics with a scope trying to figure this one out and haven't made it
yet <?>. In any case, just like those extra 1h delay lines in the chroma path
that they seem to love so much, there are work arounds. That extra 63us of
chroma delay will drive ya nuts trying to figure out why the chroma coincidence
is all screwed up until you bypass and remove it <grin>. After that bit of
circuit redesign, it is a semi-good playback deck, for S-VHS that is <g>.
Vince
Vince,
The Kitchen Sync gets its power from the Amiga's motherboard, and the ground
for the Amiga is already lifted from the mains ground, but not connected to the
other equipment's ground loop. Think that'd be worth trying ??
Jerry
Jerry, sorry about that <g>. Guess I'm so used to individual components that I
forgot about the TBC being an integrail part of the Amiga system. Well, if the
Amiga is floating from ground, you could give that a try but I'd think that the
shields on the cables would bring everything into the loop. Never hurts to try
something new, though. We've got a 16×4 copper plate which everything is tied
to for a frame ground. That connects to the cold water pipe at the point which
it comes in from the main feeder pipe and has a separate ground rod that is
strapped to everything else. The ground from the buss ties back with RG-11
cable using the center conducter and the shield is tied in with a 0.01
capacitor to give some RF shielding (one of those old HAM radio tricks for an
electrically short ground connection) since there are a couple of HF and VHF
transmitters in use that will drive everything nuts without it. So far the
only problem I've ever had was a difference between the mains ground and the
frame ground. With everything going through an UPS, that was easy enough to
solve by breaking the mains ground at the distribution point and using a common
frame ground. Maybe not the best way of doing things, but it did solve a
number of intermittent problems that were driving us nuts.
Vince
Vince,
You've inspired me to go ahead and drive a ground rod outside and connect all
my grounds to it; who knows, I may improve my audio and video in the
process…
Jerry
Jerry, if you do, be sure to isolate everything from the mains ground to avoid
a potential ground loop or tie that mains ground buss directly into it as the
distribution with an electrically short connection. Luck to ya as I know first
hand what a PITA stray garbage in the chain can be.
Vince