Re: cctv camera no image

["Just Looking" <nospam@xxxxxxxxxx>]

When you have a dispute with a DVR manufacturer over issues like dropping a
camera from the grabber card, or a recording freeze up, many times the DVR
manufacturer blames the camera manufacturer (or the installation itself and
therefore you). If you install ground isolation transformers and such to fix
the problem, and nothing you try seems to be working to fix the issue, in
many cases measurements with instruments like these are the only way for the
higher level DVR tech support guys to take you or the problem seriously. On
problem installations a meter like this can be a life saver. Fortunately
those don't happen often. So I guess it is a function of the volume of
installations you perform to decide whether or not to get a meter like that.

"Group Host" <group@xxxxx> wrote in message
news:iioWi.64$di.24@xxxxxxxxxxxxxxxxxxxxxxxxx
> thought about getting one of those.  what so you think, are they worth the
> price?
>
> "Roland Moore" <nospam@xxxxxxxxxx> wrote in message
> news:4729f3ad$0$24276$4c368faf@xxxxxxxxxxxxxxxxx
> > >That is incorrect.  At the BNC connector you will >typically see about
> > >1V,
> > P/P.
> >
> > Trying to explain that to the OP not knowing what meter or setting he
has
> > available is tough, especially since he was told by one poster he would
> > not
> > see anything. On some color cameras I have seen it as high as 1.4 volts
> > peak
> > to peak. We use a meter that costs more than half a grand to measure
CCTV
> > problems. I am sure you've seen one or maybe had one. It allows you to
> > focus
> > the camera just by looking at the numbers alone without ever having to
see
> > an image. There are other useful measurements there for finding problems
> > with video as well. Maybe you could figure out a way to make money
renting
> > them to customers doing their own large conventional CCTV installations?
> >
> > <robertlbass@xxxxxxxxxxx> wrote in message
> > news:1193872093.427755.68150@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> >> On Oct 29, 4:53 pm, resisto...@xxxxxxxxx wrote:
> >> > On Oct 29, 2:21 pm, e.dav...@xxxxxxxxxxxx wrote:
> >> >
> >> > > What could be the cause of a cctv camera suddenly having no image?
> >> > > There is still a power LED coming on, but no signal coming through.
> >> > > I
> >> > > have tested the voltage on the BNC output and it shows 0V.
> >> >
> >> > Well you should not have any voltage on the BNC connector.
> >>
> >> That is incorrect.  At the BNC connector you will typically see about
> >> 1V, P/P.
> >>
> >> > You should
> >> > have 2 conductors for power. But if the led is on then you have
power.
> >> > So either the BNC end went bad especially if it is those junk twist
on
> >> > ones
> >>
> >> That is also incorrect.  Twist-on connectors have been in use for
> >> years without failing.  You have to strip the cable correctly to use
> >> them effectively.  Soldered or press-on types are better for high def
> >> signals.  However, very few CCTV systems are HD.
> >>
> >> > or something blew the camera. I have had that happen twice in the
> >> > last couple weeks
> >>
> >> That or a loose connection are the most likely culprits.  If there are
> >> other, functioning cameras in the system, swap the bad with a known
> >> good one.  First try swapping BNC inputs at the DVR or monitor end.
> >> If the problem remains the same the DVR or monitor has a problem.
> >> This isn't as likely but it's the easiest thing to check so do that
> >> first.
> >>
> >> If the problem follows the swapped input, restore it and swap the
> >> camera with a known good one.  If the problem stays the same it's a
> >> bad cable or BNC connector.  If the problem follows the swapped
> >> camera, then the camera is at fault.
> >>
> >> Regards,
> >> Robert L Bass
> >> www.BassBurglarAlarms.com
> >>
> >
> >
>
>