On Mon, 18 Apr 2005 02:43:05 GMT, "Michael A. Terrell"
wrote:


http://www.switchcraft.com/products/vpp.html &
http://www.switchcraft.com/products/561.html are examples of video patch
bays and plugs that work for HF receivers as well. They are used for
manual routing of video in some studios and transmitter sites. Western
Electric used to use them on their coaxial long lines that fed video
cross country before TV satellites were available. If you're old enough
to remember the nationwide live video feed after President Kennedy was
assassinated, the techs and engineers at ATT patched together the first
nationwide feed by connecting the different network's feeds together to
provide all network stations with live video and did the same with the
audio feeds.
75 Ohms, if that matters.

If you're going to use RG-59/U, you might as well just use
ubiquitous and cheap F-Connectors and A/B/C switches.

David wrote:

On Mon, 18 Apr 2005 02:43:05 GMT, "Michael A. Terrell"
wrote:

http://www.switchcraft.com/products/vpp.html &
http://www.switchcraft.com/products/561.html are examples of video patch
bays and plugs that work for HF receivers as well. They are used for
manual routing of video in some studios and transmitter sites. Western
Electric used to use them on their coaxial long lines that fed video
cross country before TV satellites were available. If you're old enough
to remember the nationwide live video feed after President Kennedy was
assassinated, the techs and engineers at ATT patched together the first
nationwide feed by connecting the different network's feeds together to
provide all network stations with live video and did the same with the
audio feeds.
75 Ohms, if that matters.

If you're going to use RG-59/U, you might as well just use
ubiquitous and cheap F-Connectors and A/B/C switches.


If you want to use 75 ohm cables its your choice. The patch bays are
BNC on both halves so you can use 50 or 75 ohm cables with them. These
patch bays show up used and surplus along with the plugs. I've used
them at several TV stations, a mobile production van I built and in the
telemetry package we shipped to Italy. They are a lot better quality
than "F" fittings and CATV switches. I used to run insertion loss and
other tests on samples for United Video Cablevision and there was more
junk submitted than quality parts. Even the better quality switches
only lasted a year or so when we used them to reroute video feeds in the
L.O. studio.

--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

On Mon, 18 Apr 2005 13:33:03 GMT, "Michael A. Terrell"
wrote:



If you want to use 75 ohm cables its your choice. The patch bays are
BNC on both halves so you can use 50 or 75 ohm cables with them. These
patch bays show up used and surplus along with the plugs. I've used
them at several TV stations, a mobile production van I built and in the
telemetry package we shipped to Italy. They are a lot better quality
than "F" fittings and CATV switches. I used to run insertion loss and
other tests on samples for United Video Cablevision and there was more
junk submitted than quality parts. Even the better quality switches
only lasted a year or so when we used them to reroute video feeds in the
L.O. studio.

75 Ohm BNCs and 50 Ohm BNCs are two different connectors. You can mix
them up if you like, but it's lame.

David wrote:

On Mon, 18 Apr 2005 13:33:03 GMT, "Michael A. Terrell"
wrote:


If you want to use 75 ohm cables its your choice. The patch bays are
BNC on both halves so you can use 50 or 75 ohm cables with them. These
patch bays show up used and surplus along with the plugs. I've used
them at several TV stations, a mobile production van I built and in the
telemetry package we shipped to Italy. They are a lot better quality
than "F" fittings and CATV switches. I used to run insertion loss and
other tests on samples for United Video Cablevision and there was more
junk submitted than quality parts. Even the better quality switches
only lasted a year or so when we used them to reroute video feeds in the
L.O. studio.

75 Ohm BNCs and 50 Ohm BNCs are two different connectors. You can mix
them up if you like, but it's lame.


"N" connectors are the really touchy connectors as far as pin and
collet diameters.

I would worry more about the intermod problems from worn contacts in
cheap A-B switches. I've seen it and had to track it down in places
that were too cheap to buy a video router or patch bay.

--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

In article ,
"Michael A. Terrell" wrote:

David wrote:

On Mon, 18 Apr 2005 02:43:05 GMT, "Michael A. Terrell"
wrote:

http://www.switchcraft.com/products/vpp.html &
http://www.switchcraft.com/products/561.html are examples of video patch
bays and plugs that work for HF receivers as well. They are used for
manual routing of video in some studios and transmitter sites. Western
Electric used to use them on their coaxial long lines that fed video
cross country before TV satellites were available. If you're old enough
to remember the nationwide live video feed after President Kennedy was
assassinated, the techs and engineers at ATT patched together the first
nationwide feed by connecting the different network's feeds together to
provide all network stations with live video and did the same with the
audio feeds.
75 Ohms, if that matters.

If you're going to use RG-59/U, you might as well just use
ubiquitous and cheap F-Connectors and A/B/C switches.


If you want to use 75 ohm cables its your choice. The patch bays are
BNC on both halves so you can use 50 or 75 ohm cables with them. These
patch bays show up used and surplus along with the plugs. I've used
them at several TV stations, a mobile production van I built and in the
telemetry package we shipped to Italy. They are a lot better quality
than "F" fittings and CATV switches. I used to run insertion loss and
other tests on samples for United Video Cablevision and there was more
junk submitted than quality parts. Even the better quality switches
only lasted a year or so when we used them to reroute video feeds in the
L.O. studio.

I think F connectors are just plain nasty. Pain in the butt getting them
started threading. BNC is used on practically any lab equipment in the
audio and video range. Most gear operating 1KHz to 500MHz uses BNC.

Making up the BNC connector is a little more work than a PL-259 but the
push on and twist makes changing patch board connections a snap.

Just say no to F connectors unless you are using RG-59, which they are
made for and the connections will not be changed often.

--
Telamon
Ventura, California