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Installing a satellite dish

This is a replacement dish for the Comtech dish destroyed in a downburst event a few weeks ago.  The first part of the job entailed placement of the new dish down on the ground.  The town code enforcement officer was much happier with this idea than mounting it up above roof level along back the building as the old one was.  Of course, this is possible due to the shift in satellites last year to AMC-18.

Finding a good spot on the radio station property was fairly easy.  The studio is located in a business district, thus the side yard requirements where zero feet, which is great.  The building inspector required that we dig a test hole to see what type of soil was there.  It turned out to be fill.  That required the footing design be changed somewhat and stamped by a licensed engineer.  Not a major problem.

Satellite mount pole, waiting pre-pour inspection

Satellite mount pole, waiting pre-pour inspection

The footing is 36 inches wide by 7 feet deep.

A little bit of water in the bottom of the hole

A little bit of water in the bottom of the hole

The mounting pipe has flanges welded to the side of it to prevent it from spinning in the concrete.

Footing poured and cured

Footing poured and cured

After the pour, we let the concrete set up over the weekend.

New dish bolted together

New dish bolted together

The dish is assembled and waiting for lift.  We used a back hoe to lift the dish onto the mounting pole, unfortunately, I was not able to take a picture as I was on a ladder attaching the dish to the pedestal with U-bolts.

Viking 1374-990 3.7 Meter R/O dish installed

Viking 1374-990 3.7 Meter R/O dish installed

Here it is installed and aimed at AMC-18. I used the Satellite Buddy, which makes the aiming job much easier. Once the signal is acquired, I like to peak the Eb/No on the West Wood One carrier, which seems to be the most sensitive to any type of change.

Viking 1374-990 3.7 Meter satellite dish, back view

Viking 1374-990 3.7 Meter satellite dish, back view

Register those C band satellite dishes!

UPDATE:The registration deadline has been extended to October 17th, 2018. Switch back to procrastination mode…

Satellite dishs, WABC transmitter site, Lodi, NJ

Unless you have been sleeping under a rock, you should already be aware of the FCC request to register the C band Receive Only (RO) satellite dishes. This development comes from the never ending drive for more bandwidth from the mobile phone/data networks (remember the desire to use GPS frequencies for mobile data a few years ago).  Normally, this type of registration would require a full frequency coordination study, however until July 18th, this requirement has been waived.  The registration is completed online with the filing of FCC form 312 and a $435.00 filing fee.  West Wood One has supplied and example form (.pdf) which shows the required information for each dish.  Schedule B of FCC form 312 requires quite a bit of technical information required for each dish:

  • Site Coordinates (must be NAD27 according to the instructions on the form)
  • Site elevation AMSL in meters
  • Dish height to top of dish in meters
  • Dish make and model number
  • Dish size
  • Dish mid band gain
  • Emission designator (WWO uses 36M0G7W other providers may be different)
  • Eastern and Western arc limits
  • Eastern and Western arc limit elevation angles
  • Eastern and Western arc limit azimuth angles

Most of this is intuitive.  There are several steps to getting the information in the correct format.  Google maps (or other mapping programs) will give coordinates in decimal format.  To convert to Degrees Minutes Seconds in NAD27 use NADCON.  Site elevation can be found using free map tools elevation finder.  To determine the arc, a smart phone app such as Satellite Finder or Dish Pointer can be used.  If not actually on site, then Dishpointer.com can be used to determine the arc.

My best suggestion is to include as much of the arc as possible for each location.  The future cannot be predicted with any degree of accuracy and it is entirely possible that the current satellite position may not be used forever.

Wind damage

This satellite dish nearly broke off of its mount during a “macroburst” event.  According to the National Weather Service:

A macroburst is a thunderstorm downdraft affecting an area at least 2.5 miles wide with peak winds lasting 5 to 20 minutes. The macroburst is a straight-line wind phenomena not associated with rotation…used to differentiate from tornadic
winds. Macrobursts can produce as much if not more damage as tornadoes due to the size and scope of a macroburst.

On May 15th a large group of severe thunderstorms triggered at least three tornadoes and one macroburst event in eastern New York and Western Connecticut.  Winds in the macroburst area were estimated to be in the 85 to 105 MPH range.

The next morning, it took a long time to get the the clients studio.  Trees where down everywhere, roads were closed, traffic lights not working, etc.  This created numerous detours and traffic jams.  When I finally arrived at a clients studio facility, this was the first thing I noticed:

Comtech 3.8 meter dish with broken mount

Comtech 3.8 meter dish with broken mount

That is an older 3.8 meter comtech dish hanging on by one 3/8 inch stainless steel U bolt.  The funny thing is, they did not complain about this or the lack of satellite service.  The main complaint was that the studios were on generator and some of the lights and air conditioners were not working.

Comtech 3/8 inch stainless U bolt holding up 650 pound dish

Comtech 3/8 inch stainless U bolt sheared off

Comtech 3.8 meter dish support bracket twisted

Comtech 3.8 meter dish support bracket twisted

This dish had originally been put up when AMC-8 was the main commercial radio network bird in the US.  The dish elevation was only 9 degrees above the horizon, so this had to be put up next to the building at roof top level to clear the trees and see 139W.

I was attempting to secure the dish but in the end, the 650 pound dish was too tenuous and the weather was still unstable.  There was other damage to the dish thus we decided to take it down instead.  Even that took a bit of doing.  We were trying find a crane or bucket truck, but all that type of equipment had been pressed into service with recovery efforts.  We finally undid all the bolts and bracing and fell it like a tree.

Comtech dish on the ground

Comtech dish on the ground

The dish was then cut up and put in the dumpster.

The new satellite dish will be installed next to building in a lower position.

Happy New Year!

After a bit of reflection and a few good conversations over the New Year’s Holiday, I decided that I should continue my work on this blog.  I would like to thank all those that have stuck by and waited.  I have received numerous emails and messages off line, all of which have been read and appreciated.

Since the abrupt stoppage last July, which was absolutely necessary for me, many things have happened within the business.  Fortunately, during the hiatus, I was still taking pictures.  After sorting through them, here are a few interesting things that happened:

At one of our client’s AM transmitter sites in Albany, NY a 2.6 Million Watt solar system has been installed.

WROW-AM Steel mounting poles on antenna array field

WROW-AM Steel mounting poles on antenna array field

This project required many steel mounting posts be driven into the ground around the AM towers.  I don’t even know how many, but I would hazard a guess of over three hundred.  Each one of those mounting posts was hand dug down a depth of 6-10 inches to look for ground wires.  Where ever a ground wire was found, it was moved out of the way before the post was set.

WROW-AM ground wire moved out of way

WROW-AM ground wire moved out of way

Basically the solar array covers about 1/2 of the antenna array field.  All of the steel mounting hardware is tied into the ground system, making, what I am sure is a pretty large above ground counterpoise.

WROW-AM solar panel mounting hardware

WROW-AM solar panel mounting hardware

View from the south looking north:

Solar Array installed on WROW antenna array, Glenmont, NY

Solar Array installed on WROW antenna array, Glenmont, NY

View from the north, outside of the transmitter building, looking south:

Solar Array installed on WROW antenna array, Glenmont, NY

Power company interface and disconnect:

Solar Array utility company disconnect, Glenmont, NY

Solar Array utility company disconnect, Glenmont, NY

The utility company had to upgrade the transmission lines to the nearest substation to handle the additional power produced by the solar system. All in all, it was a fun project to watch happen.

At a certain studio building, which is over 150 years old, the roof needed to be replaced.  This required that the 3.2 meter satellite dish and non-penetrating roof mount be moved out of the way while that section of the roof was worked on.

3.2 meter satellite dish

Dish ready to move, all of the concrete ballast removed and taken down from roof.  The roofing contractors constructed a  caddy and the entire dish and mount was slid forward onto the area in front of it.  Since the front part of the roof was not reinforced to hold up the satellite dish, we did not reballast the mount and the XDS receivers ran off of the streaming audio for a couple of days until the dish was put back in its original position.

3.2 meter satellite dish ready to move

3.2 meter satellite dish ready to move

A couple of other studio projects have been underway in various places.  Pictures to follow…

One of our clients sold their radio stations to another one of our clients.

There has also been a bankruptcy of a major radio company here in the good ol’ US of A.  Something that was not unexpected, however, the ramifications of which are still being decided on in various board rooms.  One of the issues as contractors is whether or not we will get paid for our work.  All things considered, it could be much worse.

Learned a valuable lesson about mice chewed wires on generator battery chargers.  I noticed that the battery charger seemed to be dead, therefore, I reached down to make sure the AC plug was in all the way.  A loud pop and flash followed and this was the result:

Arc burns, right hand

Arc burns, right hand

My hand felt a bit warm for a while.  The fourth digit suffered some minor burns.  There is at least one guy I know that would be threatening a lawsuit right now.  Me, not so much…  All of the high voltage stuff we work on; power supplies that can go to 25 KV, and a simple 120 VAC plug is the thing that gets me.

The return of the rotary phase maker.

Rotary phase maker, Kay Industies T-10000-A

Mechanically derived 3rd phase used when the old tube type transmitter cannot be converted to single phase service.

Those are just a few of the things I have been working on.  I will generate some posts on current projects underway.  Those projects include a 2 KW FM transmitter installation, another studio project, repair work on a Harris Z16HD transmitter, etc

It is good to be back!

Engineering Radio; the satellite reaiming tour 2017!

As previously discussed, the migration from AMC-8 to AMC-18 is in full swing. There is less than two weeks left to complete the re-aiming process.  All totalled, we have 24 of these things to re-point and all but two of them  are done.  Toward that end, I have this down to an art:

  • Go inside and make a note of the signal strength on the satellite receivers on AMC-8
  • Look up the elevation angle on dish align app for AMC-8 then compare that to what the inclinometer reads, note the difference between the calculated and actual readings
  • Look up the elevation angle on the dish align app for AMC-18, apply the difference noted above to the final value
  • Connect the XR-3 satellite aiming tool to the LNB, make sure LNB power is on and the unit is set to AMC-18, C-band
  • Elevate the dish to the AMC-18 final elevation angle calculated above
  • Note the azimuth on the dish align app, look at the satellite picture and pick out a land mark.  Swing the dish towards the land mark
  • As you start to see signal from various satellites, swing more slowly.  If the elevation angle is set correctly, when the dish passes AMC-18 at 105 degrees W, the XR-3 will lock on
  • Peak the signal (azimuth and elevation)
  • Rotate the LNB feed horn for maximum signal to noise ratio
  • Go inside, check satellite receivers, reprogram carrier frequencies as necessary

It is pretty easy. I can do the whole thing in about thirty minutes if there are no rusted bolts, etc. I wonder how many small station owners will wake up on July 1st with no satellite programming?

Comtech Satellite dishes, WABC transmitter site, Lodi, NJ

The Applied Instruments XR-3 (XR-S2ACM-01) VSAT-ACM  satellite signal meter with AMC-18 locked.  This hand held tool is great and makes aiming any dish a snap.  As the sky around AMC-18 is a wee bit crowded, it is easy to mistakenly find the wrong satellite.  With the Identify function, the satellite the dish is aimed to will be displayed, then the dish can be adjusted accordingly to the correct bird.

Applied Instruments XR-3 satellite signal meter

There are many different flavors of dishes; Comtech, Patriot, Prodelin, etc.

Prodelin 3.7 Meter satellite dish

These are all about the same to work with, the only difference is the degree of rust and deterioration on the mounting hardware, the age of the LNB and number of bees nests that need to be removed.

Commercial Radio Networks changing Satellites

Lockheed Martin A2100 series satellite

Lockheed Martin A2100 series satellite

Westwood One, Premiere, Skyview Networks, et al. will be changing their satellite from AMC-8 at 139° W to AMC-18/SES-11 at 105° W longitude.  More from AMC8transition.com. There are several considerations for this move:

  • Dish design and two degree compliance
  • Obstacle clearance
  • Transponder frequencies
  • Timing

Two degree compliance is going to be an issue for many stations.  Those old 2.4 and 2.8 meter mesh dishes are going to have issues with 105º West because that is a very crowed part of the sky.  From New York, it looks something like this:

Satellite Longitude Inclination Azimuth Elevation Distance
TELSTAR 12 (ORION 2) 109.21° W 0.491° 227.46° 31.09° 38596.91 km
TELSTAR 12 (ORION 2) 109.21° W 0.491° 227.46° 31.09° 38596.91 km
MSAT M1 107.72° W 7.430° 231.14° 38.16° 38011.55 km
ANIK G1 107.33° W 0.013° 225.25° 31.96° 38518.62 km
ANIK F1 107.31° W 0.020° 225.22° 31.95° 38513.76 km
ANIK F1R 107.28° W 0.052° 225.22° 32.02° 38510.37 km
ECHOSTAR 17 107.11° W 0.019° 225.01° 32.08° 38503.29 km
AMC-15 105.07° W 0.025° 222.76° 33.28° 38400.67 km
AMC-18 104.96° W 0.027° 222.64° 33.34° 38400.16 km
GOES 14 104.66° W 0.198° 222.21° 33.38° 38394.57 km
AMSC 1 103.44° W 9.810° 228.37° 43.31° 37616.42 km
SES-3 103.01° W 0.041° 220.41° 34.42° 38307.12 km
SPACEWAY 1 102.90° W 0.032° 220.25° 34.43° 38299.87 km
DIRECTV 10 102.82° W 0.017° 220.17° 34.51° 38292.86 km
DIRECTV 12 102.78° W 0.035° 220.12° 34.50° 38292.93 km
DIRECTV 15 102.71° W 0.009° 220.05° 34.56° 38290.50 km
SKYTERRA 1 101.30° W 3.488° 219.07° 36.33° 38131.32 km
DIRECTV 4S 101.19° W 0.011° 218.24° 35.35° 38228.26 km
DIRECTV 9S 101.15° W 0.014° 218.18° 35.36° 38228.57 km
SES-1 101.00° W 0.016° 218.02° 35.45° 38217.56 km
DIRECTV 8 100.87° W 0.036° 217.88° 35.54° 38211.02 km

Generally speaking, dishes need to be 3.7 meters (12.14 feet) or larger to meet the two degree compliance specification.  For many, this means replacing the current dish.  This is especially true for those old 10 foot aluminium mesh dishes that were very popular in the 90’s because of the TVRO satellite craze.

If the existing dish is acceptable, then the next issue may be obstacle clearance.  Generally speaking the 105 degree west slot (south of Denver) will be easier to see that the 139 degree west slot (south of Honolulu) for much of the United States.  Still, there may be trees, buildings, hills, etc in the way.  Site surveys can be made using online tools (dishpointer.com) or smart phone apps (dishalign (iOS) or dishaligner (Android)).  I have found that I need to stand in front of the dish to get the best idea of any obstacles.  While you are there, spray all the dish holding hardware with a penetrating oil like WD-40, Rostoff or something similar.  Most of these dishes have not moved since they were installed, many years or decades ago.

Transponder frequencies will not be the same, so when the dish is aligned to the new satellite, those frequencies will need to be changed.  The network satellite provider will furnish this information when it becomes available.  This generally requires navigating around various menu trees in the satellite receiver.  Most are fairly intuitive, but it never hurts to be prepared.

The window of opportunity is from February 1, 2017 (first day of AMC-18) until June 30, 2017 (last day of AMC-8).  Of course, in the northern parts of the country, it may not be possible to install a new dish in the middle of winter.  It may also be very difficult to align an existing dish depending on how bad the winter is.  Therefore, the planning process should begin now.   A quick site evaluation should include the following:

Network Satellite Receive Location Evaluation

Satellite:

Satellite Location:

Dish is 2°compliant? (Y/N)

Distance to receiver location:

Dish Latitude:

Dish Longitude:

Dish Azimuth (T):

Dish Azimuth (M)

Dish Height AGL:

Dish Elevation:

Observed Obstacles:

(permanent or removable? Owned or not owned?)

Comments:

A .pdf version is available here. Based on that information, a decision can be made on whether or not to keep the old dish or install a new one.  We service about 25 studio locations and I am already aware of three in need of dish replacement and two that have obstructive trees which will need to be cut.  This work cannot start too soon.

The Realtek 2832U

In my spare time (lol!) I have been fooling around with one of those RTL 2832U dongles and a bit of software.  For those that don’t know, the RTL 2832U is a COFDM demodulator chip designed to work with a USB dongle.  When coupled with an R 820T tuner a broadband RF receiver is created  There are many very inexpensive versions of these devices available on Amazon, eBay and other such places. The beauty of these things is that for around $12-30 and a bit of free software, one can have a very versatile 10 KHz to 1.7 GHz receiver.  There are several good software packages for Windoze, Linux and OSX.

The one I recommend for beginners is called SDR-Sharp or SDR#.  It has a very easy learning curve and there is lots of documentation available on line.  There are also several worth while plugins for scanning, trunking, decoding, etc.  At a minimum, the SDR software should have a spectrum analyzer, water fall display and ability to record audio and baseband PCM from the IF stage of the radio.

Some fun things to do; look at the output of my reverse registering smart (electric) meter (or my neighbor’s meter), ACARS data for the various aircraft flying overhead, a few trips through the EZPass toll lanes, some poking around on the VHF hi-band, etc.  I also began to think of Broadcast Engineering applications and a surprising number of things came to mind:

  • Using the scanner to look for open 950 MHz STL frequencies
  • Inexpensive portable FM receiver with RDS output for radio stations
  • Inexpensive Radio Direction Finder with a directional antenna
  • Inexpensive Satellite Aiming tool

Using SDR sharp and a NooElec NESDR Mini+ dongle, I made several scans of the 945-952 STL band in a few of our markets.  Using the scanner and frequency search plugin, the SDR software very quickly identified all of the in use frequencies.  One can also look at the frequency span in the spectrum analyzer, but this takes a lot of processing power.  The scanner plugin makes this easier and can be automated.

950 MHz STL frequencies, Albany, NY

Analog and digital 950 MHz STL frequencies, Albany, NY

I also listened to the analog STLs in FM Wideband mode.  Several stations are injecting their RDS data at the studio.  There is one that appears to be -1500 Hz off frequency.  I’ll let them know.

Next, I have found it beneficial just to keep the dongle and a small antenna in my laptop bag.  Setting up a new RDS subcarrier; with the dongle and SDR# one can quickly and easily check for errors.  Tracking down one of those nasty pirates; a laptop with a directional antenna will make quick work.

Something that I found interesting is the water fall display for the PPM encoded stations:

WPDH using RTL 2832U and SDR Sharp

WPDH using RTL 2832U and SDR Sharp

Not only can you see the water marking on the main channel, you can also see the HD Radio carriers +/- 200 KHz from the carrier frequency.  That is pretty much twice the bandwidth allotment for an FM station.

WDPA using RTL 2831U with SDR Sharp

WDPA using RTL 2831U and  SDR Sharp

Those two stations are simulcasting.  WPDA is not using Nielson PPM nor HD Radio technology.  There is all sorts of interesting information that can be gleaned from one of these units.

Aiming a satellite dish at AMC-8 can be a bit challenging.  That part of the sky is pretty crowed, as it turns out.  Dish pointer is a good general reference (www.dishpointer.com) and the Dish Align app for iOS works well.  But for peaking a dish, the RTL 2832 dongle makes it easy to find the correct satellite and optimize the transponder polarization.  Each satellite has Horizontal and Vertical beacons.  These vary slightly in frequency, thus, but tuning to the correct beacon frequency, you can be assured that you are on the right satellite.  All of the radio network programming on AMC-8 is on vertically polarized transponders, therefore,  the vertical beacons are of interest.  Here are the vertical beacons for satellites in that part of the sky:

Satellite Position C band Vertical beacon (MHz) L band (LNB) Vertcial beacon (MHz) Comment
AMC-8 139W 4199.5 949.25
AMC-7 137W 3700.5 1450.25
GOES15 135.4W 2209.086 N/A NOAA WX
AMC-10 135W 4199.5 949.25
Galaxy 15 133W 4198 949.00
AMC-11 131W 4199.5 949.25
Galaxy 12 129W 3700.5 1450.25

For those in the continental United States, there is not much else past 139W, so AMC-8 will be the western most satellite your dish can see.  Of course, this can be used in other parts of the world as well, with the correct information. Bringing a laptop or Windows tablet to the satellite dish might be easier than trying to drag a XDS satellite receiver out.

AMC8 vertical beacon output from LNB

AMC8 vertical beacon output from LNB

In order to use the RTL-2832U, simply split the output of a powered LNB, install a 20-30 dB pad in between the splitter and the dongle.  Using the vertical beacon on 949.25 MHz, adjust for maximum signal.

Some other uses; look for the nearest and best NOAA Weather radio station.  Several times the local NOAA weather station has been off the air for an extended period of time.  Sometimes, another station can be found in the same forecast area.  Heck, couple these things to a Raspberry Pi or Beaglebone black and a really nifty EAS receiver is created for NOAA and broadcast FM.  One that perhaps, can issue an alarm if the RSL drops below a certain threshold.

I am sure there are plenty of other uses that I am not thinking of right now…

Satellite Dish Maintenance

Periodic attention is required for most satellite receive only earth stations. This particular dish sticks up above the roof line of a two story building. It acts as a big sail and sometimes, after a particular wind event, it gets slight off of it’s intended satellite, AMC-8.

Comtech 3.7 meter dish

Comtech 3.7 meter dish

The real issue is doing anything with the feed horn assembly, as it hangs way up in the air right over the edge of the roof. An extension ladder does not work, nor does a step ladder on the roof. Thus, we had to call a bucket truck to come and replace the LNB.  Naturally, this work is being done on one of the coldest days of the year (so far).  Temperatures at the start were 4° F or -15° C, which made the hydraulics in the bucket truck a bit reluctant to work.

When the dish was installed in 2000 or so, I swung it so the feed horn assembly was over the roof to work on it. This did not allow me to effectively check the feed horn polarization. With the bucket truck and a good satellite aiming device, I was able to find the correct polarization for the transponders in use by this station.

Bucket truck satellite dish maintenance

Bucket truck satellite dish maintenance

The old LNB was an original California Amplifiers PLL LNB from the mid 1990’s. The temperature was 35° K, which is kind of high these days. It was replaced by a Norsat C band PLL LNB with a 20° K temperature.

The satellite aiming tool used is an AI Turbo S2 by Dawn Satellite.  This unit has software profiles for each satellite which can be updated over the internet.  The 139° W satellite neighborhood is pretty crowded and it is easy to find yourself looking at the wrong bird.  Using the aiming tool prevents that from happening, as it tells the user exactly which satellite it is receiving.

Satellite aiming tool

Satellite aiming tool

If this is a new installation, using Satellite Finder makes the rough aiming much easier.

Dish pointer, AMC-8 aiming information

Dish pointer, AMC-8 aiming information

Also, it one were interested in being very through, consulting the SES center of box page will give the best aiming window times.  To be honest, I have never found this to make much difference.

XDS Eb/No after re-aiming

XDS Eb/No after re-aiming

The end result, Eb/No is 17.5 with the AG of 54.  All in all, a happy satellite receiver.

Mounting a new satellite dish

Something that almost every radio station has but no one really thinks about; the satellite down link. I think radio stations began installing satellite down link equipment around 1982. Before that, all network programming was carried hither and yon via Ma Bell’s extensive terrestrial microwave network.

Those early dishes were almost always Scientific Atlanta 9000 series 2.8 meter antenna system, which went with the SA 7300 DATS satellite receiver.  Fast forward 31 years and things have changed.  The satellite constellation is now spaced at one degree and those old SA 9000 dishes are not one degree compliant.

Scientific Atlanta 9000 series satellite dish

Scientific Atlanta 9000 series satellite dish

Therefore, when it came time to re-aim a dish at AMC8, something new was required.  A Prodelin 1374 3.7 meter center fed C band dish was ordered up.

The first thing to do is look at the dish specifications and decide if the suggested mounting procedure is a good one.  The soil in this area is sandy loam.  The mounting design calls for six inch schedule 80 steel pipe at least six feet into the ground.  This calls for renting an excavator, digging a six foot deep hole, buying a 36 inch sono-tube and a 16 foot piece of 6 inch schedule 80 steel pipe and a couple of yards of concrete from a truck.  This work all being done on the ground system for the WDCD antenna array.  All the while, abandoning the old pad and dish in place.  Seems like a lot of money and wasted materials.  Re-using the old pad and part of the old mount seemed to make more sense.  I did some rough calculations on paper regarding wind forces, this was the results:

WDCD satellite dish mount design

WDCD satellite dish mount design

The maximum static force is 1,555 N on the back bolts of the mounting ring into the concrete pad.  Maximum wind force is 5,603 N, a maximum wind from bearing 76° T will exert a force of 7,158 N or 730 Kg force on the back bolts of the mount.  The concrete that the mounting bolts is embedded in will withstand 4,267 Kg of force at six inches deep.  The the existing pad and 3/4 inch J bolts are well within their rating to handle this load, so it seems like a good design. Putting that to practical use:

Scientific Atlanta 9000 series dish mount

Scientific Atlanta 9000 series dish mount

First, we unbolted the azimuth mounting ring and removed the old dish, leaving the bottom of the mount.  I drilled down 6 inches into the old concrete pad and inserted 1/2 inch re-bar.  These re-bar are somewhat diagonal toward the center of the tube towards the new mounting pole.

Scientific Atlanta 9000 series dish mount reuse

Scientific Atlanta 9000 series dish mount reuse

Then, we placed the 6 inch by 8 foot schedule 80 pipe in the center of the tube and attached it to the tube with 1/2 inch all-thread.  We used the all thread to adjust the 6 inch pipe so that it was vertical.

Next, we filled the old mount up with 4,000 PSI (280 Kg/square cm) ready mix concrete and let it cure for one week.

New mount for Prodelin dish

New mount for Prodelin dish

While that was curing, I bolted the new Prodelin 1374 dish together on the ground.  Follow the directions closely on this one, there are many pieces of hardware that look the same and are almost the same but will not work if exchanged.

Prodelin 1374 dish about to be lifted

Prodelin 1374 dish about to be lifted

We used a loader with a lifting bar on it to sling the new dish into place.  I was going to video tape this evolution, but we were short handed and I ended up helping bolt the dish on the mount once it was placed there.

Prodelin 1374 dish, installed

Prodelin 1374 dish, installed

Once the dish was mounted, I installed the feed horn and LNB.

WDCD Albany, NY, Prodelin 1374 dish installded

WDCD Albany, NY, Prodelin 1374 dish installed

Then there was the aiming; this dish is pointed at AMC-8, for which I found this information from dishpointer.com most helpful:

WDCD AMC-8 information, courtesy of dishpointer.com

WDCD AMC-8 information, courtesy of dishpointer.com

This is a crowded neighborhood and finding the right satellite took a bit of trial and error.

The XDS satellite receiver

I remember, back in the day, when we all used Scientific Atlanta 7300 satellite receivers. There were two flavors of decoder cards; DATS and SEDAT.  Starting about 1982 or so, satellite distribution of network audio was a quantum leap over the old TELCO circuits used previously.  The use of satellite downlinks allowed radio stations to receive an almost unlimited number of programs from every network under the sun.

The SA 7300 receivers gradually gave way to the SA 3640, which gave way to the Starguide, Starguide II and Starguide III series which finally lead to the XDS and MAX receivers used today.

XDS satellite receivers

XDS satellite receivers

The newest generation satellite receivers are yet another quantum leap over the last, with on board hard drive storage that allows time shifting of entire shows.  Another nice thing is the web interface.  Before you know it, everything in the broadcast plant will have a web interface.

The one issue I have had with nearly every single XDS receiver is the fan going bad.  The manufacture must have laid into a supply of defective fans.  A bad fan is noted with the fault light turns red and the unit will return a “Fan stopped” error message.  The network will send a replacement fan if you let them know.  I have carefully replaced several of these fans without turning the receiver off.

Otherwise, the web interface is pretty intuitive.  Drop down menus allow for programming the audio ports on the receiver and setting up the delayed recording and playback function.

XDS satellite receiver weekly programming grid

XDS satellite receiver weekly programming grid

Any required network closures are configured in the relay screen.  The programming clock provided by the network will specify which relays are used for each show.

XDS relay maping screen

XDS relay maping screen

Each receiver has two DB-37 connectors that have 16 relays each for a total of 32 output closures.  That should be enough to cover almost any programming situation.

Finally, the receiver’s overall operating condition can be monitored via the health screen:

XDS satellite receiver health screen

XDS satellite receiver health screen

Something like this can greatly speed up any remote diagnostic trouble shooting by eliminating (or pinpointing) a satellite system failure as the reason for a station being off the air.  I also make sure that all automation systems have some type of remote access like VNC so that I don’t have to needlessly drive to the studio to fix a silly computer problem.

Then there is one more neat tool, for those XDS receivers that do not have any front panel user controls (one certain network uses these), called the “XDS discovery tool.”  I have found this bit of software to be very helpful from time to time.

Axiom


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

Free counters!