[BC] Starguide Compendium

[Tom Taggart]

The last few weeks I have been going around in circles with a certain network I won't name, (lest their big round ears burn) trying to resolve a problem with a failing Starguide satellite receiver.  Took a week to get a loaner shipped out, took another week to get an RMA for repair. Which would then have me ship the unit back to DGS & pay a nice price for repair.  On top of all that, only half the relays on the relay card in the loaner worked. 

Luckily I had purchased some spare audio cards so I could keep programing going from a second Starguide in another studio until the loaner came in.  Also had an extra relay card, which fixed the problem with the loaner.  Then I found a used receiver for sale, when that comes in I will have a complete spare. 

And this list saved me big $$$.  Turns out that the original receiver has a bad power supply, a problem that I could have  easily diagnosed and fixed earlier if I had known what the normal voltages were supposed to be. Another member of this list gave me a tip on where to find the exact replacement supply.

This all occurred after we finally cured another problem we  with receiving Premiere. Seems our look angle is only a few degrees off the incoming path from an MCI microwave tower.  Premier's downlink is at 4127 MHZ, MCI was transmitting at 4130 MHZ. We tried a variety of filters, this problem was finally resolved when we got MCI to turn off their microwave carrier. Of course, first we had to educate the MCI techs on why there was even a problem in the first place. 

So, after these problems, I thought I would pool together everything I've learned, with the idea that it may save someone else a lot of grief and some time.

Now that I have all this info, plus a spare receiver, Murphy's law will mean that the network will send their new, entirely different receiver next week.  And I will encounter  a whole new set of problems.

Starguide repair:

SVTronics/DG FastChannel Technical Center
3465 Technology Drive
Plano, Tx 75704
Phone: 214-440-1234
Fax: 214-440-1222

You could also try "Dave Wilcox" <DWilcox at dgfastchannel.com> 

Their rates are somewhat steep: repair of a Starguide III is $545; evaluation is $125 and includes two cards, or $50 per card; the EDAS cards are particularly expensive to repair.  While it appears that you need an RMA and are instructed to ship to Texas, they say that Reno, Nevada sales taxes apply on services??

Charlie Wooten in Panama City, Fla., can repair common problems with the audio cards. (charliewooten at clearchannel.com) 

Here?s some do-it-yourself info:

Power Supply: Astec LPT63 Newark Part No. 62K3455   ($60.00)

This is a triple voltage supply.  Depending on cooling, it will produce around 7~8 amps at +5 volts; 2.8~3.3 amps at +15 volts, and around an amp at -15 volts.  If the voltages are off by more than a volt, the supply is probably bad. 

In my unit, this caused the receiver to go into ?acquiring? mode but it would never lock.

This supply is mounted on the right hand side of the unit on standoffs using 4 Phillips head screws.  In order to remove the bottom two screws from the power supply, you need to remove the receiver card from the motherboard. You will need a short-handled screwdriver.  Be careful?the receiver is connected to the motherboard by a multi-pin header type of connector, mounted on the side of that card near the power supply.  You don?t want to bend the pins. 

Fan: Sunon KD0506PHB3.  This is a 5 volt DC square fan, 60 mm x 60 mm x 15 mm.  It is a ball bearing fan, low speed, with about 15 CFM.  The depth is not critical.

Used to be Allied part number 997-0073, but this number no longer stocked.  997-0532 looks similar; it would appear that any similar sized fan would work. The Sunon fan plugs into the motherboard, but you could just cut the wires and splice if you get one with leads only. 

Satellite band plans: The C-band downlink is from 3720 MHZ to 4180 MHZ, every 20 MHz.  An LNB has a local oscillator at 5150 MHZ., so your incoming L-band frequency is the transponder frequency subtracted from the LO frequency. Most services we use are on AMC 8, go to www.ses-americom.com  Then to frequencies/ C-band for their band plans.  For ABC, at transponder 23, (4160 MHz) the L-band frequency the Starguide is tuned to is 990 MHZ.  Lots of independent networks on the ABC transponder, including MRN/PRN NASCAR races.  Premier uses a split channel at 4127, they carry a number of baseball and other pro sports broadcasts.

Terrestrial interference: Telephone/data carriers: These still exist, the terrestrial microwave frequencies are every twenty MHZ between the transponder frequencies. You can go to FCC.GOV, then search, then the wireless bureau database to find microwave frequencies in your area.

We have an MCI tower 1500 feet east of us, we?ve used a screen behind our dish to eliminate much of the incidental TI.  This was built with three 12" triangular tower sections (the kind used for home TV antennas), and metal hardware cloth (like window screen material, only stiffer).

?AWACs? or military radar, is supposedly above the C band, but don?t count on it. This will be periodic pops in the signal and will seem to fade in then out as the plane passes by.  Coastal and marine navigational radar frequencies (2.9-3.65) GHz, just below the C-band, frequently wipe-out transponders 1-5 on satellite dishes installed near harbors. There are also airport altimeter signals (4.25-4.40) GHz that will affect transponders 22-24 at receive sites located near airports.

Filters: http://www.microwavefilter.com/ Makes an ?AWACS? filter that mounts on the feedhorn ahead of the LNB. Works well, about $300. Look at the 7893D series, a call to them can be very helpful. They also make fixed and tunable L-band bandpass filters that can be used to cure specific problems. We had some success with their tunable filter trying to eliminate TI on Premier, but that transponder was only 3 MHz away from the microwave carrier.

Hope this is helpful to other folks.

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