[PSUBS-MAILIST] An Idea for a PSUB Periscope

["Gary R. Boucher" <protek@shreve.net>]

     Now everyone's trying to come up with ways of solving the heat 
problem.  There is no heat problem if you simply paint your camera housing 
white.  You should be able to operate it Rio in the summer.  You don't 
really need fins or pumps or solid state cooling devices.  Just put your 
camera in a cylinder with a window, and paint it white.  Use Aluminum, 
Steel, Stainless, or Acrylic.  PVC will probably work.  I did not mention 
that I used a good amount of dessicant inside the tube.  There should be 
very little moisture to condense.
     As far as the pumps go, I have one submersible pump on my sub and it's 
sole purpose in life is to circulate water around a cooling jacket to cool 
a 6.7 Hp motor.  Talk about a pain!  If I put the pump inside the hull it 
would have to be able to withstand the pressure at depth.  Most pumps that 
operate on DC have brushes and are anything but quite especially if they 
can take a couple hundred PSI.  Submersible pumps are good to a certain 
depth before the seals give way.  I did use a submersible pump.  You can 
not even hear it.  However, I had to convert the 12V to 120 VAC to drive 
the induction motor.  I use a blood pressure bladder from a cuff just to 
compensate the pump's internals.  It's a pain.  But it does work and cool 
my motor.  The 120VAC converter for the pump is housed in an aluminum 
container.  It's all safe.
     If you use a pump to cool the periscope, which is not necessary, it 
will either have to be a submersible pump that can take rated depth or it 
will have to be housed inside or in a chamber.  Then you have to have a 
heat exchanger.  Just paint it white.

GB