Mini Cams

I just ordered the AV700 model which is slightly larger with 40GB drive
and 7-inch diagonal screen. There is a $100 rebate (yuck) through 3/31
which means it's cheaper than the AV500 with the 4-inch screen. It
appears otherwise technically identical. It'd better have the AV input
ports though or it's a return item. Will mean a larger case though.

Frank Whiteley

Couldn't tell from literature nor web site, but (as I suspected) the
AV700 docking station has the AV sockets and a power extender, so a
longer pressurization case will be needed for the AV700. The docking
station is The AV500 is a decidedly more compact unit overall if
that's of primary concern. Still awaiting the camera. The HD230CWX
camera is now called the HD230C.

Frank Whiteley

Docking station is essentially a 4" disk, 1" thick.

Frank

Frank,
If you mount the camera inside the cockpit, what do you do to eliminate
canopy reflections? I understand a polarizing lens will do this but if
the cam is mounted on your head the polarization will change as you pan
around and/or turn the glider, and/or as the sun's azimuth changes
during the day right?

Well, not sure the camera is going in the cockpit much of the time.
The camera arrived recently along with an additional 25' AV extension
cable, which added $14 to the cost, so it was hard to pass up.
Otherwise I plan also use my second Ram-Mount as a camera mount inside
the cockpit and occassionally through the slider window.
http://www.ram-mount.com/ has a lot of attachment gadgetry, including
standard camera mounts.

For some specialized video, I'm looking a some external mount points.
The camera has digital pan/tilt/3X zoom, but I haven't tested that yet.

There is a difference in the input voltage between the Archos V500 and
the V700. The V500 requires 5V which 4 * NiMH 1.2V 2500mAH cells
provide. The V700 requires 6V input which means building up a custom
holder. I'm ordering a 10-cell AA holder to modify into a 6V 2.5AH
supply for the recorder. Want to keep it self contained for use in a
variety of gliders also.

Wish the taxes were done;^(

Frank

Canopy reflection elimination may be a challenge. I've taken many
images through canopies and most work, some don't. Taking them through
the slider is often better. Other pilots have made great photos by
holding the camera outside on a stick.

Frank

Robert Hart wrote:
Frank Whiteley wrote:
Well, not sure the camera is going in the cockpit much of the time.
The camera arrived recently along with an additional 25' AV extension
cable, which added $14 to the cost, so it was hard to pass up.
Otherwise I plan also use my second Ram-Mount as a camera mount inside
the cockpit and occassionally through the slider window.
http://www.ram-mount.com/ has a lot of attachment gadgetry, including
standard camera mounts.

How are you going to secure the camera (well the hard disk) against low
pressure (going above 10,000)? I've been looking around and can't find
anything and have been contemplating how one might contstruct such a box.

Ideas?

Robert


?????

Disk drives come in a real nice metal case, it's just that the stupid
manufacturers aren't smart enough to seal them up real good. You've
got a O2 tank, don't you? 'Nuff said.

Wouldn't it just be easier to use a flash drive?

"Frank Whiteley" wrote in message
oups.com...
I plan to build a sealed case. This leads to temperature and sealing
concerns. As the field elevation at my club is 5500msl, we clearly
spend most of a good soaring day well above 10,000msl, above the rated
spec of most small HDDs. There are some drives rated to 10000m, but
I'm not sure they'd work in this device, so I'm not going there at this
point.

I plan on visiting a local aluminum vendor. They have a huge selection
as they are an outlet for Lockheed/Martin Marietta scrap. At least one
side of the case will be an aluminum heat sink for the case as I think
heat buildup is an issue with spinning a small HDD for several hours.
Could be a sandwich style with aluminun on either side of an acrylic
frame would give the most rigidity and cooling. The PSI load will get
relatively large, so latching the case shut will be the key to an
effective seal. The V500 is looking more attractive due to it's more
compact size and simple power requirements and stowage.

I'd add a small pressure gauge of appropriate scale and a strip
aquarium thermometer. Probably install a small screw valve and blow a
little pressure into the case. I envision that at our altitude, I'd
pressurize it to 1-2psi above ambient field air pressure to get a
positive indication on the pressure gauge, for confidence in the seal.
It could simply be closed at ambient pressure also. Since any small
pressure gauge is going to register a relative increase in pressure,
near sea level sites to maybe 5000msl with the expectation of going
above 10000msl, sealing might be enough as the gauge would indicate
positive pressure during climb. I think I'd consider the effects of
density altitude also, since on a hot, relatively humid day, airfield
density altitude is getting close to the operational limits of the HDD.

The HDDs have a low pressure limit, but they also have a high pressure
limit of about -1000ft/-300m msl which is 15.23psi, so real care with
positive pressurization is warranted.

Frank

The engineering's already been done. Just found this great web site
on exactly this topic:

http://i_fly_5000k.home.comcast.net/disk_fix/





Frank Whiteley wrote:
I plan to build a sealed case. This leads to temperature and sealing
concerns. As the field elevation at my club is 5500msl, we clearly
spend most of a good soaring day well above 10,000msl, above the rated
spec of most small HDDs. There are some drives rated to 10000m, but
I'm not sure they'd work in this device, so I'm not going there at this
point.

I plan on visiting a local aluminum vendor. They have a huge selection
as they are an outlet for Lockheed/Martin Marietta scrap. At least one
side of the case will be an aluminum heat sink for the case as I think
heat buildup is an issue with spinning a small HDD for several hours.
Could be a sandwich style with aluminun on either side of an acrylic
frame would give the most rigidity and cooling. The PSI load will get
relatively large, so latching the case shut will be the key to an
effective seal. The V500 is looking more attractive due to it's more
compact size and simple power requirements and stowage.

I'd add a small pressure gauge of appropriate scale and a strip
aquarium thermometer. Probably install a small screw valve and blow a
little pressure into the case. I envision that at our altitude, I'd
pressurize it to 1-2psi above ambient field air pressure to get a
positive indication on the pressure gauge, for confidence in the seal.
It could simply be closed at ambient pressure also. Since any small
pressure gauge is going to register a relative increase in pressure,
near sea level sites to maybe 5000msl with the expectation of going
above 10000msl, sealing might be enough as the gauge would indicate
positive pressure during climb. I think I'd consider the effects of
density altitude also, since on a hot, relatively humid day, airfield
density altitude is getting close to the operational limits of the HDD.

The HDDs have a low pressure limit, but they also have a high pressure
limit of about -1000ft/-300m msl which is 15.23psi, so real care with
positive pressurization is warranted.

Frank

LOL - Great line!

"Use dining room table to backstop the drilling, to eliminate burrs."