Power

You can never have too much power......

Electron Beam Deflection

As part of our investigation of electron tubes, we have a small CRT (bottom center) to experiment with. We have 5KV (right meter) for the second anode supplied from a cable tester (large black box). The two white dots on the screen are a result of driving a single deflection coil with a 555/power transistor circuit. Note the small stream of smoke in the lower right corner as we exceed the power capacity of a current limiting resistor.

Revised Pressure Chamber Design

Here's the revised design for the pressure chamber with a cable bulkhead. Cables will first enter the the cable bulkhead via a water proof seal. Connections to the pressure chamber will be via sealed connectors.

Proposed Dome Mount Design

This shows the current design to mate the acrylic dome to the body of the pressure chamber. A double seal would be formed with a gaskets (not shown) under the ring and under the flange of the dome.

Time Delay Water Switch

This is an earlier design David created. It is a normally-off switch. The delay is activated as the switch is submerged. Inside the chamber is a large spring compressing two copper contacts seperated by an Alka-Seltzer tablet. One possible application is to turn on the underwater camera lights after the craft has decended below the surface.

Underwater Video camera & Lamp

This was our first design for an underwater video camera and light source. These were used during our first test dive down the well.

First Dive Video

This is a video from our first test dive with our first underwater video camera design. This dive is in a residential fresh water well approximately 30 feet deep.

Pressure Chamber Model

This is the first draft of a design for a new pressure chamber rendered in SketchUp. We have an estimate from a local welding shop to fabricate the main body out of aluminum or stainless steel. The bottom section will be a double bulkhead chamber for connections to the surface cable and to sensors/actuators on the ROV.

Unipolar Stepper Motor & Control Circuit

David constructed this circuit today using a uni-polar stepper motor IC (seen upper right) he selected and ordered earlier. This device, an Allegro/Sanken SLA7026M, is a high power (3.0 amp peak) controller. It does require a bit more support circuitry as it does not have a translator on board and the (step) truth table requires control of four inputs simultaneously to sequence each step. Initially, it appeared that the circuit was operating as the holding torque on the motor could not be overcome manually. We may have suffered a chip burn-out for unknown reasons as there is no further response; investigating now. The very large stepper motor seen in the upper left is out of an HP Laserjet 3si (a monster).

Underwater Structures to Investigate

There are lots of interesting structures underwater that suggest investigation. This is an example in the channel fairly deep into the harbor. There are some remarkably large features in the sound that are also high on our target list.