DSES Science Meeting Nov 23, 2020

These are the slides from our DSES Science Meeting, held online on November 23, 2020. The science meeting was led by Rich Russel, and moderated by Bill Miller.

http://dses.science/wp-content/uploads/2020/11/DSES-Science-Meeting-11-23-20.pdf

We plan to upload the agenda and notes for the meeting soon also.

Installing the 1296 MHz feed for Autumn Moon Bounce Communications

Text and photos by Gary Agranat.

A DSES team worked at the Plishner Radio Telescope site in Haswell on Sunday September 27, 2o2o. Team members were Ray Uberecken, Floyd Glick, and Gary Agranat. We accomplished the main objective, to install a new 1296 MHz feed at the focus of the 60 dish antenna. We also installed a mast in the ground, on which will later be added a Hughes Internet satellite antenna. Two friends of Ray’s came out and did an immense service by using metal detectors and magnetic rollers to clear nails and other metallic debris on the site. We changed out two of the locks. And we inspected the bunker.

Mast for Hughes Internet antenna

Ray and I met at the Plishner site at 0930 in the morning. 

We first installed a sturdy pipe mast behind the operations trailer, on which will be mounted a small satellite antenna to access the Hughes network geosynchronous satellite for Internet access.  Ray chose a spot that will not be blocked by the trailer or the 60-foot antenna.  We mixed cement and set the pole in its hole with the cement, using a level to check that the mast is vertical.

Moon Bounce (EME) Preparation

After that we manually rotated the 60-foot dish antenna to the service platform. I figured out, with Ray’s help and the checklists, how to use the software to monitor the antenna pointing. (Note: we might want to add a checklist just for this type of procedure, for using the software for just manual antenna pointing, as when we service the antenna.)

Floyd came out to the site by 1030. Ray and Floyd climbed the service platform. I worked on the ground to move feeds and tools up and down to them. We replaced the 408 MHz feed at the antenna focus with the newly built 1296 MHz feed. The 1296 MHz feed was built by KL6M, to specifications provided by Steve Plock (KL7IZW). The feed mount at the dish focus was designed by Ray, to enable the feed to more easily rotate out and be changed.

Conditions were somewhat windy, with a cold front coming, but still manageable. By the afternoon the winds had picked up enough that we postponed any further work at the feed. Work that still needs completion is installation of a 200 Watt amplifier at the feed. Since we are planning to operate at 1296 MHz from the Operations Trailer, which has a long coax hard line path to the pedestal and antenna feed, we expect significant power loss from the long path. We therefore need to boost the power again at the feed. We plan to install the amplifier the next weekend. We then also intend to test our setup by trying tropospheric scatter communications to the north.

We are planning to use this configuration to operate EME (Earth Moon Earth) Moon Bounce communications. And specifically we plan to participate in the ARRL EME contests on October 10-11, 2020 and on November 28-29, 2020 (UTC).

We discussed our plans for the upcoming contest in 2 weekends. The Moon then will be at last quarter phase. What that means is that it will rise on Friday night a little before midnight (about 1130 PM), and set Saturday a little after 2 PM. That means we will prepare to do overnight and morning operations. After the Moon rises we will try to pick up the ON0EME beacon in Belgium. We can try to contact across the Atlantic Ocean. The US East Coast will be in night time conditions, and so we anticipate less contacts to there. Daytime conditions, when more hams would be awake, are more favorable for the US West Coast, and across the Pacific Ocean to Oceana, Asia, and Australia.

Note that the 60-foot antenna will be configured with the 1296 MHz feed through the end of November. This will be an opportunity to try using it for other 1296 MHz communications, including troposphere scatter.  

Metal souring of the site

A friend of Ray’s who works at Planet Granite Ryan, and his brother, Rob, came out to the site also.  They have ground metal detectors and magnets on rollers, and systematically paced across the site to pick up nails and other small metallic debris.  They did pick up lots of nails, including along the roadway. They spent a few hours with us, and left after lunch. They did us a great service by helping remove a lot of this debris.

Combination Lock and Bunker Inspection

We attempted to open the combination locks at the gate, the bunker, and the generator shack. After still having difficulty, we replaced the locks at the gate and bunker, with the locks Myron Babcock obtained for us. These are similar model locks, and the combinations were kept the same.

We had a report that the bunker had been flooded by two successive rain storms in July. We opened and inspected the bunker. The bunker was dry, though the floor had more-than-normal dust and dirt, and some tiny debris was spread here and there. It will require a fresh cleanup before normal use. We saw no indication of mold from dampness.

Tumbleweeds were accumulated again at the ramp entrance.

We completed our activities by early afternoon, about 3 PM.

For the team, – Gary

We kept the antenna steering in manual configuration. We opened the System 1 steering software to monitor the position angles as we manually steered the antenna to the service platform.
We noted this radio interference at the site on our scope. This scan is from 0 to 1.8 GHz. The higher floor noise level at the left is from the sensitivity of our 408 MHz feed, which was still on the dish antenna, before we changed it out.
The 60-foot antenna is positioned for service.
Ray brought two feeds for the 60-foot antenna. This is Ray showing Floyd the 4 GHz feed, which we will use in the future, to calibrate the pointing position with geosynchronous satellites.
Floyd carrying the 1296 MHz feed to the antenna for installation.
The inside of the 1296 MHz feed. It is designed as a septum feed, with separate channels on each side for left and right circular polarization.
Rob with a metal detector, crisscrossing the site, picking up small metal debris.
Ray and Floyd on the 60-foot antenna service platform, starting work.
Removing the cover.
Ray is disconnecting the 408 MHz feed, so that it can rotate down and out for changeout.
The 408 MHz feed is now rotated down. It is connected simply by the shaft to the mount, for easier changeout.
Installing now the 1296 MHz feed. Its design doesn’t use a shaft, but instead will be securely fastened to the mounting frame.
Ryan using a metal detector on the west side of the site.
Our view towards the west. High clouds in the distance are an indication of a cold front gradually coming this way. We experienced steady windy conditions as the front approached..
Closing up.
Our view of Haswell in the distance. The clouds from the front were getting closer. By the time we left in mid-afternoon, the clouds were over us, but we had no precipitation.
The 1296 MHz feed installed.
We installed this ground mast. It will mount a small satellite antenna, to connect to the Hughes Internet network.

New work area in the science trailer, built by Bob Haggart

Bob Haggart (N0CTV) has been steadily improving the workspace of the science trailer at the Plishner radio telescope site. During the pulsar observation work on May 2, 2020, he completed building his latest enhancement: a partitioned work space at the east side of the science trailer. There is desktop space, which can be used for electronics building and testing. And there is additional shelf space, for better organization and storage.

Thank you Bob!

The new partitioned work area, seen from the middle of the science trailer.
New desktop workspace, with room for building and testing. There is also close access to test equipment, references, and technical documentation.
The work space in use during the pulsar observations on May 2, 2020.

System 1 antenna control system update April 13, 2020

By Glenn Davis

I thought I would put out a System 1 status, so you can see what we’ve been working on the past couple of months.  To quickly summarize:  Lewis Putnam has been concentrating on the System 1 hardware design (Please see the hardware diagram below) to support automatic tracking of the Haswell Mount.  Additionally he has been looking at the individual mount axis characteristics to see how well they can support sidereal tracking (See detail text below). 

Phil Gage has supported myself looking at an Elevation axis movement issue we had seen at the site.  We found a loose cable on our March 1 trip which appeared to be causing the elevation axis issues.  Additionally, Phil has been working on the hardware/software interface for the Labjack hardware (Please see the hardware diagram below).  The Labjack hardware, the U3 and JTick-DAC components, will be used to control the mount axis rates.

I have been updating the System 1 Hardware Simulator to support the Numato Relay Board and Labjack U3/JTick-DAC hardware devices.  Additionally, I’ve been working on the hardware/software interface to the Numato Relay board.  This device will be used to enable the drive controllers and control the direction of the Elevation Axis.  Using the work completed by Phil and the Simulator modifications, I’ve been able to test and debug most of the automatic tracking software modifications and simulate the System 1 tracking celestial objects over large periods of time (hours).    

Here is a more detail summary of the past work and future work on the System 1 team (Before site modifications are performed, we will present our design work to the DSES Engineering Team):

March 12 2020 Trip

  • Purpose: Determine relationship between Az / El drive command voltages and rate resulting from command voltages
  • Approach:
    • Made measurements to calibrate mount Az and El drives (Rate as function of applied voltage)
    • Took measurements separately for Azimuth and Elevation
    • Measured both CW and CCW rates for Az and Up/Down rates for Elevation 
    • Varied voltage via Trailer Control Panel Az and El rate potentiometers from 0 to 5 volts (.2-volt increments for voltages below a volt and 1-volt increments from 1 volt to 5 volts.)
    • Logged axis position data in System 1 software
    • Captured measurements in Excel spreadsheet and plotted
  • Findings:
    • Plotted results indicate linear relationship between voltage and rate for both positive and negative rates for both axes.
    • Performed linear fit to determine slope and intercept values that can be used to convert an axis rate into a command voltage.
    • Unique Slope and intercept parameters will be used in System 1 software
    • Slowest drive rates are .02 deg/sec for Az and .06 deg/sec for Elevation; lowest rates were consistent between positive and negative rates
      • Rates needed for sidereal track are about an order of magnitude lower
      • Will have to cycle axis drives on / off to achieve sidereal track rates
    • Elevation Potentiometer voltage will not go to zero
      • Lowest voltage is somewhat less than .2 volts
      • Cause is unknown but potentiometer is most likely candidate
    • Measurements for Elevation similar to results from August 2019 but measurements for Az significantly different from August results, unknown cause
    • Measurements in March were more extensive and disciplined. Will use calibration from these measurements in the implementation of the software.

System 1 Mount Drive Interface Hardware Design/Implementation

  • Progress:
    • Completed hardware circuit design
      • Interfaces to the tower drive electronics via the Jones Plug
      • Uses a Labjack U3 device / TickDAC that provides two +-10-volt Digital Analog Convertors to enable setting Az / El axes control voltages
        • Labjack has necessary digital I/O to interface to the axes encoders so downstream can be used to replace the now obsolete Integrity Systems digital I/O board
      • Uses Numato 8 Relay Board to enable the drive controllers and control direction in the Elevation Axis
    • Developed an approach to integrating circuit into the trailer rack
      • Mount components on a small rack shelf about 6” deep
      • Mount shelf on back rails of the Trailer Rack
      • Move Jones cable from Manual control panel to System 1 Drive Control when using System 1 for drive control
    • Acquired major components and some minor components – Numato 8 Relay Board, Labjack interface device, Jones plug and wire
  • Next Steps:
    • Colorado Springs
      • Acquire remaining additional components – Switch, LEDs, resistors, rack shelf/panel
      • Mount components on rack shelf and wire components together
      • Integrate / test software with drive control assembly
    • Site
      • Install rack shelf / panel
      • Install updated software
      • Test / debug automated drive control

Please pass this on to other individuals who may be interested.

Thank you.
Glenn Davis

Radio astronomy observing and antenna repair at the Plishner observatory, February 15, 2020

Participants: Rich Russel, Bob Haggart, Glenn Davis, Lewis Putnam, Bill Miller, and Gary Agranat.

Photos by Bill Miller and Gary Agranat.

We worked at the Plishner antenna site in Haswell on Saturday February 15, 2020. We had three projects:

  1. Attempt at observing a circumpolar pulsar, utilizing the System 1 manual tracking system. (Rich Russel, Glenn Davis, Lewis Putnam).
  2. Complete building and installing shelf space in the Communications (Operations) Trailer (Bob Haggard).
  3. Repair of the 3-element Yagi ham radio antenna, to realign the three elements (Gary Agranat, Bill Miller, Bob Haggard).

1. The major task of the day was an attempt at a science observing run of a circumpolar pulsar. This is one of the brighter puslars in the sky. And being circumpolar, it is always above the horizon, though it can still get relatively low to the horizon. The observing technique required continually pointing a the celestial coordinates and integrating the signal for at least a half hour. By integrating over time, the random noise tends to cancel more, leaving the actual radio source signal the time to accumulate and sum to a higher level than the noise floor.

Science Lead Rich Russel (seated) and System 1 Lead Glenn Davis setting up the pulsar observations.
Bill Miller, Lewis Putnam, Rich Russel, and Glenn Davis in the Communications Operations Trailer during the observation runs.
The display for the System 1 manual tracking. The circles in the black field represent the antenna beam width for different frequencies. The large blue ring represents a 4 degree diameter beam width, and is for the 408 MHz feed currently being used for the pulsar observing. The inner yellow ring is 0.8 degrees in diameter, which is for our HI hydrogen observing at 1.4 GHz. The pink dot represents where the center of the beam is pointing. A star field map is projected on the background black field. The upper part of the display shows azimuth and elevation of the antenna, and its conversion to the celestial coordinates of Right Ascension and Declination at the current time.
The signal strength across the frequency spectrum being observed. For pulsar observing, we cannot detect the pulsar signal itself in real time. We must integrate the signal over at least a half hour of observing. Then we process the signal, with an expected pulsar timing. That process averages out the background noise while adding the actual pulsar signal enough to elevate above the noise floor — in theory.
The 60 foot dish antenna turning to aim at the pulsar.
The 408 MHz antenna feed. Ray Unberecken has designed a base for the antenna feeds so that these can be easily swiveled out for service and changeout. Ray designed and built this feed.

2. Bob Haggart worked on completing the building of desk and shelf space in the Communications Operations Trailer. The additional space is actually important, as that gives us a means to organize and better utilize our work space, and not instead have items pile up randomly.

Bob Haggart
New desk and shelf space in the Communications Operations Trailer.
New desk and shelf space in the Communications Operations Trailer. Note the addition of amenities, of microwave oven and coffee pots.

3. A third project was the repair of the front element of the 3-band Yagi ham radio antenna on the 40-foot tower. The front element had rotated slightly askew.

The front element of the 3-band Yagi ham radio antenna on the 40-foot tower rotated askew somehow. Fixing this was our third project undertaken this day.
The tower was rotated down for service.
Bill Miller aligning the front element. Also working on this were Gary and Bob. Bob utilized cable lengths to help ensure actual evenness. We also used squares and levels.
Gary working on the antenna. The ladder was used to access and retighten the center supports at the mast.
While the tower was down for the service, Bill reinforced the structural support for the 2-meter band vertical antenna on a side support from the tower.
Gary raised the tower back up.
The 50-foot tower almost at its vertical position.

After the tower was raised back to vertical position, Bill and Gary slightly rearranged the positioning of the 80 meter dipole that is supported from a pulley on the tower. The repositioning separated the dipole with better clearance from other nearby wires

We discovered that the Communications Trailer phone used for our 2-meter talk-in radio was transmitting but not receiving. Bill started to troubleshoot it.
Bill photographing the dish antenna. Pikes Peak is visible in the distance, over a hundred miles away.
Gary also photographed the dish antenna.
The 60 foot antenna rotating back to its parking position after the observing runs.

Rich Russel processed the observation data, but the processing did not bring out the pulsar. Troubleshooting is a topic at the February Science Meeting. Meanwhile, the System 1 antenna pointing system worked well.

The group finished up the work well before sunset, so that traveling back with the sun setting was not a significant issue. We had good weather for this trip, for a winter day in February. Our temperature was in the 40s F, which was actually midler than the 30s in Colorado Springs. And our wind was light.

Work trip at the Plishner antenna site, Saturday November 16, 2019

Text and photos by Gary Agranat.

As we do each third weekend of the month, we had a scheduled work day at our DSES Plishner radio astronomy antenna site in Haswell, Colorado. Our members who participated on this weekend were Steve Plock, Ed Corn, Ray Uberecken, and Gary Agranat. Work objectives were:

  • Completion of installing the antennas and cables on the new 50 foot ham radio antenna tower.
  • Servicing the 60-foot dish antenna feed.
We typically meet first at the Ellicott firehouse for carpooling, before heading to the Plishner site.

I will save discussion of the 60-foot antenna feed for the Engineering Meeting minutes. That work was done by Steve Plock and Ray Uberecken. In this post I will describe the work we completed for the 50 foot tower.

The 60-foot dish antenna was rotated to the service tower, to enable Steve to work at the feed point.

For our 50-foot tower work, we installed a second vertical antenna for normal contacts on the 2-meter VHF band. This gives us a second 2-meter band capability, independent of our already existing 2-meter band talk-in radio. We then installed coax cables for both of the 2 meter band antennas on the tower.

We also serviced the 80 and 160 meter band dipole antennas that the tower supports: 1) We replaced some of the nylon rope that lifts the dipole antennas to their deployed positions. Previously we had connected shorter pieces of rope and knotted those together. But the knots stuck in the pulleys, and we therefore replaced those with longer sections of rope without knots. 2) We neatened the arrangement of the wire antennas supported by the tower.

Captions to the photos provide more detials of the work.

Ed and Gary lowered the 50-foot ham radio tower. A second VHF 2-meter band vertical antenna was added to the side of the tower, in addition to the VHF talk-in radio antenna placed last month at the top of the tower. And coax cables were added that feed both VHF antennas.
The second VHF 2-meter band antenna was added here, at this upper location along the side of the tower. Two stand-off support arms were bolted to the tower. Then the antenna was connected to its mast, which fits from below as a sleeve fitting. And the mast was connected to the supports. The mast serves both for structural support and as a counterpoise.
The tower raised up again.
The tower supports these ham radio antennas.
The tower supports the 160 meter band and 80 meter band dipole antennas by rope and pulley systems. The 160 meter antenna is oriented east-west, and the 80 meter antenna is oriented perpendicularly north-south.
Ed’s work truck on site.

After we serviced the ham and radio astronomy antennas, Steve made us lunch by smoking beef sausage in the grill. That was served with coleslaw and potato salad. Gary also brewed coffee.

After the tower was raise back up, Gary operated on phone and FT8, using the tri-band Yagi on 15 and 20 meters, and using the 80 and 160 meter dipoles. (10 meters was tried also but with no results, likely due to the poor propagation conditions.) The operating was in part for fun, and in part to verify that the antennas we put back up functioned properly. They all functioned well.

After lunch I did some ham radio operating using the tri-band Yagi, and also the using the 80 and 160 meter dipoles.  With the tri-bander, I first made a phone contact to Hawaii on 15 meters, before the bands got busy with the ARRL sweepstakes.  Then I operated FT8: on 15 meters I mostly contacted South American stations (lots of Brazil), plus some US stations when they were there (including North Carolina and Montana).  On 20 meters the band opened across the Pacific.  We had many calls to us from Japan. Perhaps they saw our profile on QRZ, or perhaps they noticed our rare grid square.  Also across the Pacific, we made two contacts with South Korea, one with mainland China, one with Indonesia, and one with Australia.  The band became weaker for US and Canadian contacts, but we did have some of those too.  I alternated going to 80 meters, and had a few more domestic contacts there. These were with our K0PRT station callsign. Later I also used my callsign, on 20, 80, and 160 meters. 160 meters had noise at the FT8 frequencies. But I went to the upper portion of that section of the band, which was just slightly better. I managed 4 contacts on 160 meters, to as far away as Kentucky. I would say our antennas were working well.

Within a few days we received a number of e QSL confirmation cards.

The site at the end of the day.

Ray left after lunch. Ed and Steve left before sunset. Steve tested the range of the new talk in radio antenna on the tower as he and Ed drove home away from the site. We had good contact to as far away as Sugar City. At JRs in Ordway, we could hear each other, but Steve needed to turn off his squelch. And at that point there were some slight dropouts. But we could still communicate. That is a great improvement for our talk-in system. Gary stayed and operated the ham station until a little after dark, and then closed up and departed too.

Antenna Raising

Plishner Antenna Site Work Trip Report. By Gary Agranat. Photos by Steve Plock.

Ed Corn, Steve Plock, and Gary Agranat traveled to the Plishner antenna site in Haswell this past Saturday, October 19, 2019. The team completed erecting the 50-foot ham radio tower.

Completing the tower erection involved several tasks:

  • Installing the 3-band/3-element Yagi HF ham antenna,
  • Installing the 2-meter band vertical antenna on top of that mast. This will be our new antenna for our VHF talk-in radio system.
  • Installing two stand-off bracketed supports near the top of the tower on the sides, to raise and hold the 80 meter band and 160 meter band dipole wire antennas. This arrangement replaces the long pole that previously centrally supported those wire antennas. These bracket supports each have a pulley and rope, to raise and lower the wire antennas. The tower also supports a 6-meter band delta-loop antenna, which is simply tied from height.
  • Securing the coax cables for the Yagi and vertical antennas along the side of the tower.
  • Properly arranging the system of wires, coaxes, and support cables.
  • Raising the 50-foot tower, which involves turning the winch system that rotates the tower up from its pivot plate at its base. The 50-foot tower is raised from a pulley system on a second smaller adjacent tower.
  • Once the 50-foot tower is raised, securing 3 guy cables.
Steve took this photo of Ed and Gary at the completion of the tower raising.

Steve tested the SWR of the 3-band Yagi antenna with an analyzer. The antenna elements had been measured and assembled on a previous trip, to be optimized for the middle of each of the operating bands, of the 10, 15 and 20 meter bands. Steve measured an SWR ratio of 1:1 (perfect) at 28.51 MHz for the 10 meter band, and 1:1 at 21.19 MHz for the 15 meter band. The 20 meter band resonated with an SWR of 1:1.35 at 14.16 MHz. This is excellent, and as expected.

For lunch, Steve treated us with smoked ribs from Broken Bones BBQ in Monument, with sauces, potato salad, and coleslaw. Gary brewed coffee. Also, the team met first at the firehouse in Ellicott. Gary baked orange-cranberry muffins. We ate our muffins at the firehouse, and shared the rest with the fire department crews there.

The team left the Plishner site by 4:30 pm.

The tower work began about a year ago. The work involved support and efforts by a number of team members. See our past posts from October 19-21, 2018 http://dses.science/plishner-site-report-for-the-weekend-of-october-19-21-2018, August 24, 2019 http://dses.science/plishner-work-trip-report-august-24-2019, and September 28, 2019 http://dses.science/work-site-trip-report-at-the-haswell-plishner-radio-telescope-site-september-28-2019.

The tower should significantly improve our capability to communicate long distances on the 10, 15, and 20 meter bands with the Yagi. The 2 meter band vertical should enable us to communicate on our talk-in VHF radio system to much further out.

Work Site Trip Report, at the Haswell Plishner Radio Telescope Site, September 28, 2019

by Gary Agranat

DSES Participants: Gary Agranat, Ed Corn, Bob Haggard, Bill Miller, Steve Plock.

Ed, Gary, and Bill met first at the Ellicott Fire Department, while Steve and Bob each traveled ahead solo. Ed encountered a problem with his truck and had to return home, but he passed the tower antenna mast and connector supplies to Bill. Steve and Bob arrived at the site by 9 AM, and Bill and Gary arrived by 10 AM.

We encountered light drizzling rain and low clouds on the route to the site, but the rain let up once we were on Highway 96 past Ordway. Steve called Ed to let us know the weather was good at the site. The weather completely cleared later, while the temperature remained comfortable.

Steve coordinated by phone with Skip Crilly and commenced a 48-hour long SETI drift scan at -7.5 degrees declination, run simultaneously with Skip’s antenna in New Hampshire. The 48 hour run will scan the -7.5 degree declination band twice, and therefore acquire a repeat set of data that can be compared with the first set.

Bob worked at the Communications Trailer, doing carpentry and painting work. He built a wood frame seal around one of the air conditioners, fabricated and painted a seal for the solar-powered fan, and painted the third work table he had added previously. Bob told me the trailer back door hadn’t been sealing — until recently — because it actually had not been closed properly. He closed the door properly and it is now sealed, without requiring further work.

Bob at work.

Bill, Steve, and Gary worked on preparing the 50-foot ham radio antenna tower.

Bill spliced the controller feed cable and wires for the antenna rotator, and verified proper operation, with some assistance from Gary. Bill used Steve’s crimping tools. The three of us then fed the controller cable through the dog house to the tower.

Bill first checked online for the correct color code standards for the control cable wiring. Then he matched the correct colored wires from the cable to the wires on the rotator. After the wiring was completed, the rotator and controller were tested for correct operation and correct meter calibration.

At the tower outside, the rotator was attached to its base plate, and that assembly was then attached to the tower.

When we tried to fit the mast in the holding tube at the top of the tower, we found that top opening was slightly damaged, and the mast wouldn’t fit in. We then took turns filing and grinding out the hole until the mast did fit properly. Steve applied a lubricating grease, to mitigate against the mast binding stuck when rotating. Eventually we successfully installed the mast to the rotator itself. We also retrieved a guy wire cable left at the communications trailer and attached it as the third guy wire connection for the top of the tower.

Bill with Steve, filing out the top opening for the mast. You can see two of the three guy cables already attached to the top of the tower.
Steve
Gary
Bill and Steve fitting the mast at the tower top. The mast was then securely fastened to the rotator.
The 60 foot antenna positions at 39.5 degrees elevation for the 48-hour SETI run, in progress.

Before we left for the day, we had two visitors from Eads come to look at the site. We all spent a little while talking about the site and the work.

Addendum

By Gary Agranat

Bob was the first to leave, then Steve. Steve said he would check on Ed on the way home. Bill and I (Gary) convoyed out last.

While Bill and I were driving back to Colorado Springs, about an hour and a half into the trip back, an auto accident happened right in front of us, with a vehicle overturning.

The accident happened while we were driving westbound on Colorado Highway 94. It was early evening by then, about 5:30 pm, and the sun appeared above in the western sky. Bill and I had been talking on the VHF ham radio during our 2 1/2 hour drive back from the site. Bill was driving ahead of me.

A couple of miles before Rush, I saw three vehicles approaching from a long distance behind, moving faster than Bill and me, while we were going at about the speed limit. I mentioned the vehicles to Bill, and we stopped talking, anticipating they would choose to pass us soon. They did soon pass us, all three staying close to each other. We could see they were some sort of laborers, with equipment filling their vehicles and with ladders on top. The third vehicle passed us as we were going up a hill, with the solid yellow line on our side. Bill commented that car was taking risks, although they all were driving in a risky manner. There was no visibility over that hill. And furthermore we were driving into the sun. A couple of miles later we reached the town of Rush, where the speed limit lowers from 65 to 50 mph. As those three vehicles ahead approached the town, I suddenly saw the last one veer to the left side of the road, and then roll over, with its front turned facing the opposite direction. Bill and I both stopped, as did a driver heading in the oncoming direction who almost got hit. And several more cars stopped briefly. We saw one occupant lie in the grass, but he eventually got up.

Bill had a better view of the accident ahead of me. It looked to him like one of the three vehicles ahead suddenly slowed as he reached the town with the lower speed limit. The sun was right above and ahead of us, which created a greater visibility challenge. The sudden slowing apparently caught the last driver off guard, as he swerved to the right to avoid the vehicle ahead of him. But that put his right side of his car in the grass there, which caused a tire blowout and a swerve then to the left. And he overturned.

The volunteer fire department nearby responded relatively quickly. But we waited about 2 hours for a sheriff’s deputy to arrive, and then another hour for a State Patrol officer to arrive. The State Patrol was who we had to give our witness statements to. We didn’t finish with that until 8:30 pm, and I didn’t get home until 9:30.

The driver of the overturned vehicle eventually got up, but he refused medical help, although we wondered if he nonetheless might have been hurt.

Meanwhile the communities there are small, and everyone there knows everyone else. The other driver who stayed was a local woman school teacher. We chatted with her and also the volunteer firefighters, and with some of the neighbors who stopped to see if everyone was OK.

The State Patrol officer later explained to us that there were 6 accidents in the region called in within a period of 5 minutes, when our accident happened. One happened just about 9 miles further west from us on Highway 94, in the town of Yoder. That accident had injuries, and some of the firefighters who were with us then had to leave to respond to the other accident.

At a minimum, this is a reminder to take care to drive safely, especially with limiting conditions like the sun setting ahead.

Plishner Work Trip Report – August 24, 2019

By Gary Agranat

Participants: Ed Corn, Steve Plock, Gary Agranat.

Ed, Steve, and I traveled to our radio telescope site, leaving from the Ellicott Fire Department a little after 7:30 am. We encountered just a little fog on the way.

Steve worked primarily on troubleshooting the amplifier failure on the 60-foot antenna fiber optic feed. Steve found a power supply no longer functioned. He wrote me later, “Damaged parts have been ordered and will be replaced at the earliest convenience.”

The 60-foot antenna dish was rotated so that Steve could access the feed from the service tower.

Ed Corn and I worked on assembling the 3-element tri-band Yagi antenna from Myron Babcock, and then the ham radio tower by the bunker, on which the Yagi antenna will go.  We measured and reassembled the three Yagi antenna elements and the boom support for them.  We’ll wait to combine those until we are ready to attach the antenna to a mast and on to the tower.  The antenna will operate on the ham 10, 15, and 20 meter bands. We decided to set the lengths so that the antenna tunes best in the center portions of the bands.

Assembly of the three elements of the tri-band Yagi antenna and its supporting boom.

We assembled the tower components out to a length of 50 feet, including the top that will hold the rotor. The tower is now designed and built to rotate from a pivot point next to the existing tower that had been started earlier.  Ed climbed that original tower to install the pulley; the pulley leverages and pulls up the 50-foot tower by rotation at the pivot.  We tested lifting the 50 foot tower with the hand crank winch that I think came from Steve.  The design works.  We eventually will need to take down the mast that supports the 80 and 160 meter dipole antennas, to complete the tower build-out.  We plan to re-attaching those antennas to the tower itself, when we are ready to complete the tower.  Ed has already fabricated two standoffs that will attach to the sides of the tower, and centrally support the dipole antennas.

Ed from time to time went to help Steve. And Steve once in a while came to help with the tower assembly.

The base of the new antenna tower pivots next to the already existing support tower. The rotating winch on the support tower will pull the antenna tower and lift it up or down.
On each of the three connecting tubes, on each of the tower elements, a set of two screws each were bolted to fasten the connections.
Ed Corn attached a pulley (fabricated before) to the support tower.
Three of the 10-foot antenna tower sections connected, and connected with the base pivot. The cable from the winch has been threaded through the pulley on the support tower above, and connected to about the 20-foot point on the antenna tower. The pipe mast visible in the photo is the center support for the existing 80 and 160 meter dipole antennas. The new antenna tower, besides supporting the directional antennas at top, will replace that mast and support those dipoles.
We tested rotating up the antenna tower with three 10-foot sections assembled. After Ed verified that the placement of the pulley was good, he securely fastened it.
The winch with cable installed, used to lift and lower the antenna tower for service. The handle crank is geared. The lock pin enables free movement, movement in one direction, and locking.
The top section of the tower, ready to be attached.
Steve helped Ed and I complete the final assembly of the tower.

We had a lunch break together in the bunker. I brought a small coffee maker and brewed coffee for Ed and me.

The weather was good, considering the heat we’ve been having lately.  High cirrostratus and mid level clouds from storms in the distance covered us for the afternoon, and kept the heat and sunshine comfortable.  We saw rain showers in the far distance, but those never came close enough to bother us. The bunker thermometer read 75 F, and outdoors was probably just a little warmer.

The Radio Jove phased dipole antenna array.
Bob Haggard’s steps provide much easier access to the Communications Trailer.
Sunflowers were blooming everywhere.
The bunker antennas in their configuration right now.

During a break I got on the air at the bunker station, and made 12 contacts for QSO parties that were running: 1 to Hawaii, 5 to Ohio, and 6 to Kansas, on CW and SSB, on 20 and 40 meters. I submitted our logs to those QSO parties later.

The 5 band vertical ham radio antenna, still in good working condition after the repair from the May storm. Photo taken in the late morning soon after we arrived. We used this to make our 12 ham radio contacts on the 20 and 40 meter bands.

For the team, Gary Agranat.