Figure: Black Azimuthal BCAM. Inside the enclosure are a Black Azimuthal BCAM Head (A2048L) and two Black Azimuthal BCAM Side Heads (A2049L).
| Schematic | PCBs | Assembly |
The Azimuthal BCAM Head (A2048) is a Long-Wire Data Acquisition (LWDAQ) Device that reads out one TC255P image sensor and drives two light sources. When the A2048 is connected to an Azimuthal BCAM Side Head (A2049), these light sources are laser diodes (LDP65001E or equivalent). A BCAM is an optical survey instrument.
The following versions of the A2048 exist.
| Version | Description |
| L | Black Azimuthal BCAM Head (mirror image of A2048R) |
| R | Blue Azimuthal BCAM Head (mirror image of A2048L) |
The A2048L is designed to operate with the Black Azimuthal BCAM Side Head (A2049L) and the TC255P Minimal Head (A2016L) in a Black Azimuthal BCAM. The A2048R is designed to operate with the Blue Azimuthal BCAM Side Head (A2049R) and the TC255P Minimal Head (A2016R) in a Blue Azimuthal BCAM.
The A2048 connects to a LWDAQ driver (such as the A2037) or multiplexer (such as the A2046) with a LWDAQ cable.
The A2048 complies with the LWDAQ Specification. It device type 2 (TC255P) for the purpose of device-dependent jobs. The lasers are elements 3 and 4, with 3 being the inner laser and 4 being the outer laser.
| DC16 | DC15 | DC14 | DC13 | DC12 | DC11 | DC10 | DC9 | DC8 | DC7 | DC6 | DC5 | DC4 | DC3 | DC2 | DC1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| X | X | X | ON4 | ON3 | X | X | X | WAKE | LB | ABEN | ABGD | IAGD | SAGD | SRGD | DCEN |
The figure below shows how the signals ON3 and ON4, which correspond to element numbers 3 and 4 during a flash job, correspond to the lasers on each type of Azimuthal BCAM.
The Blue Azimuthal BCAM is a mirror image of the Black Azimuthal BCAM. Laser 3 is on the right when seen from the front, instead of on the right. This exchange of positions allows us to distinguish between black and blue azimuthal BCAMs in our field of view.
In operation, the A2048 is very similar to the Polar BCAM Head (A2051). When connected to an Azimuthal BCAM Side Head (A2049) and TC255P Minimal Head (A2016), the A2048 provides light sources and image capture for an Azimuthal BCAM.
The A2048 provides image capture with and without ant-blooming. We discuss anti-blooming in the Anti-Blooming section of the Camera Head (A2056) Manual. When reading an image out of the A2048, we use the same steps presented in the Operation section of the Polar BCAM Head Manual. For more image acquisition details, see the Discussion section of the Inplane Sensor Head (A2036) Manual.
The A2048 provides two laser-diode point sources. We flash these sources in the same way we flash the sources of a Polar BCAM Head (A2051 ).
The A2048 can turn on its lasers only if the metal cases of its lasers are isolated from the BCAM chassis. The anodized surface of the Azimuthal BCAM isolates the laser packages from the aluminum. Provided there is an adequate and accurate chamfer on the inner rim of the laser mounting hole, there will be no risk of a short-circuit between the laser and the chassis. Without the chamfer, however, the anodizing does not provide isolation. We discovered the importance of the chamfer when we made Azimuthal BCAMs without chamfers on their laser mounting holes. We were forced to chamfer, strip, and re-anodize six hundred chassis, and even then the isolation was not reliable. We test every Azimuthal BCAM made with these original chassis for a connection between the chassis and the lasers, and if there is such a connection, we reject the BCAM and refurbish it.
For a discussion of image geometry, and how to translate between points in the image sensor and points in the image on our computer screen, see the Image Geometry section of the TC255P Minimal Head (A2016) Manual. For instructions on finding Pin One on a TC255P, see the Pin One section of the same manual.
We discuss the image quality provided by our various TC255P readout circuits in the Image Contrast of the A2036 Manual.
We picked an A2048L at random and measured its power consumption in three states. The A2048L was connected to an A2049L and an A2016L.
| State | +15 V | -15 V | +5 V | Total Power |
| Asleep | 10 μA | 10 μA | 2.9 mA | 14 mW |
| Awake (0 images/s) | 40 mA | 35 mA | 3.2 mA | 1.1 W |
| Awake (6 images/s) | 40 mA | 40 mA | 3.4 mA | 1.2 W |
| One Laser On | 70 mA | 40 mA | 3.4 mA | 1.6 W |
Note: All our schematics and Gerber files are distributed under the GNU General Public License.