foggy morning at the VLA
NRAO - Bob Broilo, Electrical Engineer
Updated May 28th, 2015
Perhaps you wanted my personal page?



Introduction- about Bob Broilo
Photos of the VLA and VLBA
Servo System Data
Tech Reports
Monitoring: HVAC and power- VLA and VLBA
Maintenance Procedures
Movies- time lapse video taken at the VLA
Weird Science- unsolicited, wacko email


Welcome to Bob Broilo's work page. Bob is an Electrical Engineer stationed at the Very Large Array (VLA) site. The telescope is located 50 miles West of Socorro, NM. Bob does engineering support for the VLA, VLBA, ALMA, EVLA, and other projects. He is also the supervisor for the HVAC/Plumbing group, Electricians, Radio Communications and general electronic maintenance.

Servo System Data

Inner Wye Plan - Inner wye antenna locations, arm angles, and soft limits.
Outer Wye Plan - Outer wye antenna locations, arm angles, and soft limits.
Array Relationships - North, West and East arm angle offsets.
Array Azimuth - Another angle relationship map
Arm to Arm changes - How to set the old-style enocder system for arm changes.

Docs for the ACU/FRM to MIB interface: Schematic, PIC code, Interface Control Document.
Board pix, 1:small, large, 2:small, large, 3:small, large.

Tech Reports

B-array Transformer Survey May 2011
A-array Transformer Survey July 2011
D-array Transformer Survey October 2011
C-array Transformer Survey April 2012
D-array Transformer Survey April 2013
C-array Transformer Survey August 2013
B-array Transformer Survey November 2013
A-array Transformer Survey May 2014
D-array Transformer Survey August 2014
C-array Transformer Survey January 2015
An attempt to identify array breakers that need replacement before they start to fail.

VLBA Memo 83: North Liberty Rail Maintenance July 2010
Efforts to repair and improve the azimuth rail.

EVLA Memo 45: Antenna Positioning System Specifications
Complete Input/Output and and performance specification for the VLA servo system.

VLA Technical Report No. 76 - Absolute Position Encoder Electronics Upgrade
Uses AD2S82 to convert Inductosyn signals into 25 bit angular position data with a size 11 resolver for coarse position.

Addendum to VLA Technical Report No. 76
Production Design for Encoder Upgrade
- updated 5/13/2002

Purchasing logbook source code for the logbook program I wrote for the NRAO-NM purchasing department to synchronize activities in the VLA and AOC. NOT Y2K COMPLIANT. I guess that doesn't matter now until 2099.

wind.lst Intel 8751 code to read 12-bit antenna anemometer data and display on an LCD for transporting antennas.


VLA power quality logs - Logs of two power monitors watching the incoming VLA power feed.
VLBA HVAC plots - The VLBA station building and antenna HVAC data for the last week.
VLBA HVAC plot archive - Historical data.

Maintenance Procedures

Adjusting encoders to minimize PN3DB errors - How to adjust an NRAO encoder to minimize cyclic pointing errors. This should be done before the encoder is installed in an antenna, and also if PN3DB errors appear while the antenna is in service.


vla_move_110914.avi Foggy move (20.6MB) - Moving VLA antennas from A-array to D-array, September 14, 2011.

DVD quality, done with a digital SLR and a timer circuit, stitching the stills together using the fantastic linux program dvd-slideshow
080808_vla.mpg Monsoon Rain (13.0MB) - A monsoon buildup and thunderstorm cell, August 8, 2008.

These older time lapse videos were done with a cheap webcam and free software.
Antenna 17 Seperation (22.7MB) - with text commentary, of the seperation of antenna 17 to change the azimuth bearing.
VLA Monsoons (16.0MB) - deep monsoonal activity and an antenna move, August 2, 2001.
VLA Monsoons (13.3MB) - typical monsoonal morning buildup over the Gallinas Mountains, July 19, 2001.
VLA Clouds (7.0MB) - VLA antennas pointing (repositioning) through low clouds, June 26, 2001.
VLA Clouds (17.6MB) - storm clouds building at the VLA, June 28, 2001.
VLA Dawn (5.3MB) - dawn at the VLA, July 19, 2001.
VLA Dawn and Antenna Move (10.0MB) - dawn during a reconfiguration at the VLA, June 27, 2001.
VLA Thunderstorm (4.1MB) - small thunderstorm at the VLA, June 21, 2001.
VLA Thunderstorm (3.8MB) - a big dark thunderstorm that forms over the VLA and then moves East, June 26, 2001.
VLA Thunderstorm (5.9MB) - a small thunderstorm that continuously forms over the Gallinas Mountains and moves over VLA, June 27, 2001.
VLA Monsoons (13.3MB) - typical monsoonal morning buildup over the Gallinas Mountains, July 19, 2001.

Weird Science

Unsolicited, whacko stuff I have received via the miracle of email. I especially like the ones that address me as "Doctor".
Unified Theory of the Universe (168KB text) - Wave tubes! Of course!
Uncertainty Principle is Untenable (58KB PDF) - An exercise in undergrad physics.

contact info for Bob Broilo

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