1 Troubleshooting. 2 Introduction This section provides you with the necessary skills to effectively...

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TroubleshootingTroubleshooting

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IntroductionIntroduction

• This section provides you with the necessary skills to effectively troubleshoot the DIRECTV System

• This section provides you with the necessary skills to effectively troubleshoot the DIRECTV System

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ObjectivesObjectives

• Test signal using a signal meter• Verify correct voltage from the IRD• Test for an open circuit• Test for a short circuit• Field test the LNB• Run a system test on the IRD

• Test signal using a signal meter• Verify correct voltage from the IRD• Test for an open circuit• Test for a short circuit• Field test the LNB• Run a system test on the IRD

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• Identifying Symptoms– No picture on television– Searching for Satellite– Missing Channels

• Identifying Symptoms– No picture on television– Searching for Satellite– Missing Channels

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• System Inspection– Animal chewed through cable– Cable jacket is damaged by weed-eater– Cable stapled or kinked– Improper ground– Improper electrical outlet– Improper Connectors– Damage to reflector or mount

• System Inspection– Animal chewed through cable– Cable jacket is damaged by weed-eater– Cable stapled or kinked– Improper ground– Improper electrical outlet– Improper Connectors– Damage to reflector or mount

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Signal Level MeterSignal Level Meter

• These 3 signal level meters are the most common used in the field today

• The signal level meter reads the level of signal in the line

• Advanced signal level meters like the BirdDog can identify specific satellites

• In Line meters may have an option that allows you to read voltage

• These 3 signal level meters are the most common used in the field today

• The signal level meter reads the level of signal in the line

• Advanced signal level meters like the BirdDog can identify specific satellites

• In Line meters may have an option that allows you to read voltage

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Quick Hit TroubleshootingQuick Hit Troubleshooting

• Determine the Signal at the IRD– Determine the defective component with SFSS

on all odd, all even or several transponders– What is the signal level

• No signal or low signal at IRD– Do a hard reboot– Check the cable connections– Read signal level at the back of the receiver

using a signal level meter

• Determine the Signal at the IRD– Determine the defective component with SFSS

on all odd, all even or several transponders– What is the signal level

• No signal or low signal at IRD– Do a hard reboot– Check the cable connections– Read signal level at the back of the receiver

using a signal level meter

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• Good signal on the meter, but not on the IRD– Check voltage out of IRD– Using a binding post adapter or a pre-made test

connector check the voltage, the black lead to the shield and the red lead to the center conductor

• Use VOM – Voltage should display as switching between 13

and 18 volts– No voltage or voltage not switching – replace

receiver– Voltage detected but no signal level on IRD –

replace receiver

• Good signal on the meter, but not on the IRD– Check voltage out of IRD– Using a binding post adapter or a pre-made test

connector check the voltage, the black lead to the shield and the red lead to the center conductor

• Use VOM – Voltage should display as switching between 13

and 18 volts– No voltage or voltage not switching – replace

receiver– Voltage detected but no signal level on IRD –

replace receiver

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The Volt Ohm Meter• VOMs can read AC or DC

voltage

• VOMs can read resistance in Ohms

• VOMs are battery powered when checking resistance

The Volt Ohm Meter• VOMs can read AC or DC

voltage

• VOMs can read resistance in Ohms

• VOMs are battery powered when checking resistance

Ω

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The Volt Ohm Meter• All VOMs have 2 leads or

probes

• Connecting Leads

• Reading Voltage

The Volt Ohm Meter• All VOMs have 2 leads or

probes

• Connecting Leads

• Reading Voltage

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The Signal Level Meter– Can read voltages at the LNB loaded

• This means that the Signal Level Meter reads the true voltage on the line with the draw from the LNB

The Signal Level Meter– Can read voltages at the LNB loaded

• This means that the Signal Level Meter reads the true voltage on the line with the draw from the LNB

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Troubleshooting In Line ComponentsTroubleshooting In Line Components

• No Signal from ODU Cable– Are there other receivers on the account?

• If yes, are they working? – If they are, the problem is isolated to this

receiver and feed– Proceed to the multiswitch or ODU;

whichever is feeding this outlet

• No Signal from ODU Cable– Are there other receivers on the account?

• If yes, are they working? – If they are, the problem is isolated to this

receiver and feed– Proceed to the multiswitch or ODU;

whichever is feeding this outlet

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• No Signal from ODU Cable– If you have very weak or no signal at the

port, test the other ports and see if they are working properly

• If the other ports are providing adequate signal but this one isn’t, replace the multiswitch

• If all ports have low signal level check the input signal to the multiswitch

• No Signal from ODU Cable– If you have very weak or no signal at the

port, test the other ports and see if they are working properly

• If the other ports are providing adequate signal but this one isn’t, replace the multiswitch

• If all ports have low signal level check the input signal to the multiswitch

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• Signal coming in from multiswitch is low– Common Problems

• Electrical Surge• Corroded/Damaged “F” Connectors• Incorrect or Damaged Cable• Moisture Migration• Poor Return Loss• Failed Internal Parts

• Signal coming in from multiswitch is low– Common Problems

• Electrical Surge• Corroded/Damaged “F” Connectors• Incorrect or Damaged Cable• Moisture Migration• Poor Return Loss• Failed Internal Parts

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• If the signal coming into the multiswitch is low, go to the ODU and check the output at the LNB. – If low or no signal, look to see if there are

any obstructions blocking signal– If there is clear line if sight attempt to

realign the ODU to peak signal– If you can not get signal replace the LNB

• If the signal coming into the multiswitch is low, go to the ODU and check the output at the LNB. – If low or no signal, look to see if there are

any obstructions blocking signal– If there is clear line if sight attempt to

realign the ODU to peak signal– If you can not get signal replace the LNB

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• Good Signal From ODU– Test the drop to the multiswitch or the

defective receiver for an open or a short

• The Volt Ohm Meter– Reading Resistance

» Shorts, opens and damage

• Good Signal From ODU– Test the drop to the multiswitch or the

defective receiver for an open or a short

• The Volt Ohm Meter– Reading Resistance

» Shorts, opens and damage


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• Short Circuit Test– Disconnect cable on both ends– Set multi-meter to ohms– Touch one lead to center conductor and

the other to the braid.– Meter should read 0, open or infinite– A short will be indicated by a fluctuating

or constant resistance

• Short Circuit Test– Disconnect cable on both ends– Set multi-meter to ohms– Touch one lead to center conductor and

the other to the braid.– Meter should read 0, open or infinite– A short will be indicated by a fluctuating

or constant resistance

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• Open Circuit Test

– Remove the cables from the LNB

– Short cable using 75 ohm terminator

– Set multi-meter to ohms

– Touch one lead to center conductor and the other to the braid

• Open Circuit Test

– Remove the cables from the LNB

– Short cable using 75 ohm terminator

– Set multi-meter to ohms

– Touch one lead to center conductor and the other to the braid

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• Open Circuit Test (Continued)

– Meter should read 75 ohms or greater, the longer the cable the greater the resistance in the circuit (Approximately. 1.6 Ohms per 100 feet of RG-6

– An indication of an open circuit would read 0, open or infinite

• Open Circuit Test (Continued)

– Meter should read 75 ohms or greater, the longer the cable the greater the resistance in the circuit (Approximately. 1.6 Ohms per 100 feet of RG-6

– An indication of an open circuit would read 0, open or infinite

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• Damaged Cable Test– Check the resistance of a terminator which

should read approximately 75 Ohms:• Firmly holding the black probe to the outer case and

firmly pressing the red probe to the center conductor

• Once the resistance is known, connect the terminator to one end of the cable and read the resistance at the other end using a binding post adapter or an adapter you made.

• Damaged Cable Test– Check the resistance of a terminator which

should read approximately 75 Ohms:• Firmly holding the black probe to the outer case and

firmly pressing the red probe to the center conductor

• Once the resistance is known, connect the terminator to one end of the cable and read the resistance at the other end using a binding post adapter or an adapter you made.

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• Good Signal From ODU– Consider the Voltage drop, attenuation and

insertion loss• Use a signal level meter to calculate cable

attenuation using a fixed scale for RG11, RG6 & RG59

• Good Signal From ODU– Consider the Voltage drop, attenuation and

insertion loss• Use a signal level meter to calculate cable

attenuation using a fixed scale for RG11, RG6 & RG59

Loss estimate per 100 feet at 68º F at 1450 MHz•RG11 = -5.29 •RG6 = -7.89 •RG59 = -9.82

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The Signal Level Meter– Calculating cable attenuation at 2150 MHz

The Signal Level Meter– Calculating cable attenuation at 2150 MHz

Loss estimate per 100 feet at 68º F at 2150 MHz•RG11 = -6.60 •RG6 = -9.69 •RG59 = -12.10


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• Good Signal From LNB– Calculate the signal loss between the

ODU and multiswitch• Consider the cable loss and insertion

loss of other component– Look for defective components– Check each device to determine the signal

level coming in and out– If you suspect the drop is defective test

for a short or open

• Good Signal From LNB– Calculate the signal loss between the

ODU and multiswitch• Consider the cable loss and insertion

loss of other component– Look for defective components– Check each device to determine the signal

level coming in and out– If you suspect the drop is defective test

for a short or open


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• In Line Devices– The cable used for a DIRECTV installation

should always be approved RG6 coaxial.– Signal Loss:

• Impact at 950 to 1450 MHz– 7.89 dB per 100 feet


• Voltage drop per 100 ft at 18 volts with 300 milliamp draw

– .48 volts per 100 feet

• In Line Devices– The cable used for a DIRECTV installation

should always be approved RG6 coaxial.– Signal Loss:



• Voltage drop per 100 ft at 18 volts with 300 milliamp draw

– .48 volts per 100 feet

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• Power Loss - dB– Some Signal Meters on the market can

show you the dB values as well as signal strength

– Generally you will see dB values at the ODU around - 32dB

– The DIRECTV receivers can still show picture at levels no less than - 60dB

– F-Connectors give you - .5dB loss per– F-81 barrels give you - 1dB loss per

• Power Loss - dB– Some Signal Meters on the market can

show you the dB values as well as signal strength

– Generally you will see dB values at the ODU around - 32dB

– The DIRECTV receivers can still show picture at levels no less than - 60dB

– F-Connectors give you - .5dB loss per– F-81 barrels give you - 1dB loss per

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• Good Signal From LNB– Calculate the signal loss between the ODU and

multiswitch• Consider the cable loss and insertion loss of

all other components.– Is the loss greater than your calculation?

If so:» Is the cable all RG6?» Are all components rated for the

frequency spectrum you need for the receiver

• Good Signal From LNB– Calculate the signal loss between the ODU and

multiswitch• Consider the cable loss and insertion loss of

all other components.– Is the loss greater than your calculation?

If so:» Is the cable all RG6?» Are all components rated for the

frequency spectrum you need for the receiver


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• Good Signal From MultiSwitch• If the drop feeding the multiswitch now has good signal

at that location check the output of the switch again• If the drop feeding the multiswitch has no signal at that

location and there are no in-line components replace that cable run

• You can run a temporary drop to confirm a cable problem

• If there are any in line components test the input signal and output signal of each to determine which has failed

• Replace any defective components or cable and reconnect the feed to the switch

• Good Signal From MultiSwitch• If the drop feeding the multiswitch now has good signal

at that location check the output of the switch again• If the drop feeding the multiswitch has no signal at that

location and there are no in-line components replace that cable run

• You can run a temporary drop to confirm a cable problem

• If there are any in line components test the input signal and output signal of each to determine which has failed

• Replace any defective components or cable and reconnect the feed to the switch


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Using Test EquipmentUsing Test Equipment

Open Ground

Open Neutral

Open Hot

Hot/GroundReversed

Hot/NeutralReversed

Correct

•The scale on the unit enables you to determine the status of the outlet

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SummarySummary

• Now that you have completed this section you should be able to:– Test signal using a signal meter– Verify correct voltage from the IRD– Test for an open circuit– Test for a short circuit– Field test the LNB– Run a system test on the IRD

• Now that you have completed this section you should be able to:– Test signal using a signal meter– Verify correct voltage from the IRD– Test for an open circuit– Test for a short circuit– Field test the LNB– Run a system test on the IRD

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ExerciseExercise

• Hands-On

– Station #1 Verify Voltage & Signal Strength

– Station #2 Open and Short Circuits

– Station #3 Troubleshooting Wall

• Hands-On

– Station #1 Verify Voltage & Signal Strength

– Station #2 Open and Short Circuits

– Station #3 Troubleshooting Wall

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