On Mon, 14 Feb 2005 21:07:37 GMT, Dan Best
wrote:

I dissagree.
The antenna that the energy is radiating off of is much wider than the
mast, so while some of the energy is reflected and scattered, most of it
just flows right on past. The reverse happens with the reflected
energy. As a result, the targets are weaker, but should still be there.
If this were not the case, then whenever you had a mast mounted radar,
everything in a fairly wide cone behind you would be invisible and this
is obviously not the case.

Thanks to you and Otnmbrd for these answers.

On a related topic, make sure that you mount the display where it can be
seen by the helmsman. A friend of mine has it mounted where it can only
be seen at the nav station and having played radar officer calling up
instructions to the helm on a foggy night in SF Bay while dodging
freighters, I'm here to say that that's not how you want to set it up.

It would tend to "compound errors", certainly. I've installed
something on my current boat, however, that I haven't seen before. I
got a gooseneck armature from an old draftsman's flourescent light and
clamped it so that it swings into the companionway. It can be lashed
in position with shock cord, if needed, but usually the friction knobs
do the trick.

On the armature I've secured a handheld GPS on "ship's power" (a 12 V
cigarette lighter style adapter). This means I can reference the GPS
quickly without using my hands, and without it being loose in the
cockpit, without eating batteries (they go through AAs in 2-3 hours of
continuous use), without losing "satellite lock" (because they are on
all the time and in the companionway can "see" enough sky).

Other advantages are (mostly) out of the weather (a ziplock bag will
do the trick here as well).

Of course, I have a tiller, which means I am standing most of the time
by the companionway near the winches and aft of the traveller on the
cabin-top.

I wonder, however, if my "armature idea" would be useful for any
similar devices, as opposed to a "hard-mount" at the wheel? If, for
instance, you had a 15" LCD panel and a wireless mouse, the panel
could be some distance away and still be readable.

R.

rhys wrote:

It would tend to "compound errors", certainly. I've installed
something on my current boat, however, that I haven't seen before. I
got a gooseneck armature from an old draftsman's flourescent light and
clamped it so that it swings into the companionway. It can be lashed
in position with shock cord, if needed, but usually the friction knobs
do the trick.

I've seen this type of mount on many boats, though not using the
draftsman's armature. I think the catalogs have brackets intended to
swing out in the companionway.




On the armature I've secured a handheld GPS on "ship's power" (a 12 V
cigarette lighter style adapter). This means I can reference the GPS
quickly without using my hands, and without it being loose in the
cockpit, without eating batteries (they go through AAs in 2-3 hours of
continuous use), without losing "satellite lock" (because they are on
all the time and in the companionway can "see" enough sky).

Other advantages are (mostly) out of the weather (a ziplock bag will
do the trick here as well).

Of course, I have a tiller, which means I am standing most of the time
by the companionway near the winches and aft of the traveller on the
cabin-top.

I wonder, however, if my "armature idea" would be useful for any
similar devices, as opposed to a "hard-mount" at the wheel? If, for
instance, you had a 15" LCD panel and a wireless mouse, the panel
could be some distance away and still be readable.

My current boat, being a catamaran, has a powerboat-like helm station
with the radar mounted on a swinging arm to the side. My previous boat,
had a clever idea that might be of use to some - A hatch was mounted in
the bulkhead in the forward end of the cockpit, and the radar (a large
crt) was mounted on a shelf inside. Its a nice solution for a display
that is too large to mount on an arm. However, once you get used to
have the controls at the helm, its hard to see how you can properly use
a radar that isn't nearby.

On Tue, 15 Feb 2005 11:34:15 -0500, Jeff Morris
wrote:

However, once you get used to
have the controls at the helm, its hard to see how you can properly use
a radar that isn't nearby.

As I said, my current boat is tiller-steered, so I am only arm's
length from the mainsheet traveller *forward* of the hatch, never mind
the companionway itself. Reaching for anything and steering involves
using my knees and leaning. If I use the tiller extender, I can go
into the galley and get a refreshing beverage, or lash it in place and
go forward to handle sails. It's not a small boat, either...nearly 34
feet.

Makes me wonder why tillers haven't stayed popular, except that I know
if's because socializing in the cockpit trumps steering.

But that's another topic, perhaps.

R.

I have two singout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other. Unfortunately, there just wasn't
quite enough room to attach both devices to just one arm, my hatch just
isn't tall enough to have them one above the other. When both are
deployed so the helmsman can see them, it's a little inconvienient since
to in or out of the hatch, you have to either carefully step over them
or swing one of them out of the way. In reality, this is not a big deal
since the radar is only rarely used (but when we do use it, we are
REALLY glad we have it).

Fair winds - Dan Best

rhys wrote:
It would tend to "compound errors", certainly. I've installed
something on my current boat, however, that I haven't seen before. I
got a gooseneck armature from an old draftsman's flourescent light and
clamped it so that it swings into the companionway. It can be lashed
in position with shock cord, if needed, but usually the friction knobs
do the trick.

On the armature I've secured a handheld GPS on "ship's power" (a 12 V
cigarette lighter style adapter). This means I can reference the GPS
quickly without using my hands, and without it being loose in the
cockpit, without eating batteries (they go through AAs in 2-3 hours of
continuous use), without losing "satellite lock" (because they are on
all the time and in the companionway can "see" enough sky).

Other advantages are (mostly) out of the weather (a ziplock bag will
do the trick here as well).

Of course, I have a tiller, which means I am standing most of the time
by the companionway near the winches and aft of the traveller on the
cabin-top.

I wonder, however, if my "armature idea" would be useful for any
similar devices, as opposed to a "hard-mount" at the wheel? If, for
instance, you had a 15" LCD panel and a wireless mouse, the panel
could be some distance away and still be readable.

R.

On Tue, 15 Feb 2005 20:35:24 GMT, Dan Best
wrote:

I have two singout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other. Unfortunately, there just wasn't
quite enough room to attach both devices to just one arm, my hatch just
isn't tall enough to have them one above the other. When both are
deployed so the helmsman can see them, it's a little inconvienient since
to in or out of the hatch, you have to either carefully step over them
or swing one of them out of the way. In reality, this is not a big deal
since the radar is only rarely used (but when we do use it, we are
REALLY glad we have it).

Exactly. Would love to see pictures and how you routed the power and
other cables to (presumably) the nav station/DC panel.

R.

"rhys" wrote in message
...
On Tue, 15 Feb 2005 20:35:24 GMT, Dan Best
wrote:

I have two singout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other. Unfortunately, there just wasn't
quite enough room to attach both devices to just one arm, my hatch just
isn't tall enough to have them one above the other. When both are
deployed so the helmsman can see them, it's a little inconvienient since
to in or out of the hatch, you have to either carefully step over them
or swing one of them out of the way. In reality, this is not a big deal
since the radar is only rarely used (but when we do use it, we are
REALLY glad we have it).

Exactly. Would love to see pictures and how you routed the power and
other cables to (presumably) the nav station/DC panel.

R.

I'm in the process of installing a JRC 2000 radar on my boat. The first
thing I did was install the display. I wanted to be able to see it/operate
it without going below. I'm using 2 horizontal RAM mount arms attached to
one of there vertical mount bases. This is bolted to a small cabinet on the
inside of the bulkhead. I can swing the display out so that I can see it
from the wheel but I don't think I'll be able to see fine detail (don't know
for sure as not fully operational yet). In this position the display blocks
access to below. I can, however swing it to the side so that I can go
forward to look at it and also go below easily. The cables are an issue
I've been wrestling with. The power and NMEA cables are not really a
problem as they are small diameter flexible wire. Easy to route. Its the
display-to-scanner cable that is the problem. Big cable and not that
flexible. I think I may have to disconnect it each time I swing the display
into its storage position inside the boat, against the cabinet. To route
this cable to the stern I'm thinking I will have to glue some white 1"
diameter water pipe to the overhead in the 1/4 berth and feed the cable
through that as I cannot get above the head liner and I need some play in
the cable. When not in use I will have a bracket on the cabinet where I can
store the cable. It will work but its not going to be as neat as I would
like.

Gordon,
Our display-to-scanner cable drops down about 18" before heading aft
through a hole in a cabinet. This plus a little slack in the cable
makes it so the cable is not unduly flexed or stressed when the arm is
swung in or out.

Hope this helps - Dan

Gordon Wedman wrote:

"rhys" wrote in message
...

On Tue, 15 Feb 2005 20:35:24 GMT, Dan Best
wrote:


I have two singout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other. Unfortunately, there just wasn't
quite enough room to attach both devices to just one arm, my hatch just
isn't tall enough to have them one above the other. When both are
deployed so the helmsman can see them, it's a little inconvienient since
to in or out of the hatch, you have to either carefully step over them
or swing one of them out of the way. In reality, this is not a big deal
since the radar is only rarely used (but when we do use it, we are
REALLY glad we have it).

Exactly. Would love to see pictures and how you routed the power and
other cables to (presumably) the nav station/DC panel.

R.


I'm in the process of installing a JRC 2000 radar on my boat. The first
thing I did was install the display. I wanted to be able to see it/operate
it without going below. I'm using 2 horizontal RAM mount arms attached to
one of there vertical mount bases. This is bolted to a small cabinet on the
inside of the bulkhead. I can swing the display out so that I can see it
from the wheel but I don't think I'll be able to see fine detail (don't know
for sure as not fully operational yet). In this position the display blocks
access to below. I can, however swing it to the side so that I can go
forward to look at it and also go below easily. The cables are an issue
I've been wrestling with. The power and NMEA cables are not really a
problem as they are small diameter flexible wire. Easy to route. Its the
display-to-scanner cable that is the problem. Big cable and not that
flexible. I think I may have to disconnect it each time I swing the display
into its storage position inside the boat, against the cabinet. To route
this cable to the stern I'm thinking I will have to glue some white 1"
diameter water pipe to the overhead in the 1/4 berth and feed the cable
through that as I cannot get above the head liner and I need some play in
the cable. When not in use I will have a bracket on the cabinet where I can
store the cable. It will work but its not going to be as neat as I would
like.

Thanks Dan
If I have enough slack in my cable I may be able to work out something
similar. I was thinking if I made a coil or two and connected them with
small shock cord it would act somewhat like a spring as I swung the display
back and forth. I would probably need to suffer the expense of buying a 15m
cable to achieve this and then I'd have a 10m cable that would be difficult
to sell. Should know in a few weeks as I'm finally getting my radar pole
together.

"Dan Best" wrote in message
...
Gordon,
Our display-to-scanner cable drops down about 18" before heading aft
through a hole in a cabinet. This plus a little slack in the cable makes
it so the cable is not unduly flexed or stressed when the arm is swung in
or out.

Hope this helps - Dan

Gordon Wedman wrote:

"rhys" wrote in message
...

On Tue, 15 Feb 2005 20:35:24 GMT, Dan Best
wrote:


I have two singout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other. Unfortunately, there just wasn't
quite enough room to attach both devices to just one arm, my hatch just
isn't tall enough to have them one above the other. When both are
deployed so the helmsman can see them, it's a little inconvienient since
to in or out of the hatch, you have to either carefully step over them
or swing one of them out of the way. In reality, this is not a big deal
since the radar is only rarely used (but when we do use it, we are
REALLY glad we have it).

Exactly. Would love to see pictures and how you routed the power and
other cables to (presumably) the nav station/DC panel.

R.


I'm in the process of installing a JRC 2000 radar on my boat. The first
thing I did was install the display. I wanted to be able to see
it/operate it without going below. I'm using 2 horizontal RAM mount arms
attached to one of there vertical mount bases. This is bolted to a small
cabinet on the inside of the bulkhead. I can swing the display out so
that I can see it from the wheel but I don't think I'll be able to see
fine detail (don't know for sure as not fully operational yet). In this
position the display blocks access to below. I can, however swing it to
the side so that I can go forward to look at it and also go below easily.
The cables are an issue I've been wrestling with. The power and NMEA
cables are not really a problem as they are small diameter flexible wire.
Easy to route. Its the display-to-scanner cable that is the problem.
Big cable and not that flexible. I think I may have to disconnect it
each time I swing the display into its storage position inside the boat,
against the cabinet. To route this cable to the stern I'm thinking I
will have to glue some white 1" diameter water pipe to the overhead in
the 1/4 berth and feed the cable through that as I cannot get above the
head liner and I need some play in the cable. When not in use I will
have a bracket on the cabinet where I can store the cable. It will work
but its not going to be as neat as I would like.

Rhys,
No big deal on routing the cables.
The radar (on the port side) has both power and control cables bound
together back into a galley cabinet where they split. The
control/signal cable heads aft through the a large storage volume we
call "the hold" on it's way to the stern mounted radar tower and the
power cable turns inboard into another cabiner behind the ladder where
all out pumps are (pressure water, sump pump out, etc). It is connected
to a fuse block in there.

The gps/fishfinder's power cable snakes under some molding to the DC
distribution panel. It's transducer and GPS antenna cables enter the
pump cabinet where the the swing out arm is mounted. From there, the
transducer cab;e goes down along the side of the engine compartment and
into the bilge where it goes forward to the transducer. The gps antenna
cable goes down into the engine copartment, then aft under the floor of
the hold to the stern, then up throughthe deck at the base of the radar
tower.

Fair winds - Dan

rhys wrote:
On Tue, 15 Feb 2005 20:35:24 GMT, Dan Best
wrote:


I have two swingout arms in my hatchway. The raday display is on one and
a gps/fish finder is on the other.

Exactly. Would love to see pictures and how you routed the power and
other cables to (presumably) the nav station/DC panel.

R.

On Fri, 18 Feb 2005 00:36:12 GMT, Dan Best
wrote:

The gps antenna
cable goes down into the engine copartment, then aft under the floor of
the hold to the stern, then up throughthe deck at the base of the radar
tower.

Thanks for the descriptions. I always learn something when I ask stuff
like this, because we are forced by technology to rethink this stuff
every few years...even though a lot of the boats are still made for
'70s and '80s considerations...

R.