leakage may occur or if the shielding braid is touching the center conductor.
2.Install model
Grainy Modulated Channel : Good Picture on the Cable Channels
1.Disconnect cable channels from the system and check the modulated channels.
A)If the modulated channels are good, use a low pass filter to
B)If the modulated channel does not improve after disconnecting the local channels, evaluate signal loss of modulator through the splitters and cable length of the system. Amplify after the combiner if needed.
C)Also check the connections between modulator and the combiner for leakage or the cable braid is touching the center conductor.
2.Make sure the attenuator adjustment on the back of the modulator is turned to maximum output power.
3.Check output strength with field strength meter.
4.Connect modulator directly to TV and check picture quality.
5.Check bandwidth of all splitters and amplifiers for 1GHz capability.
6.Place TV cable setting on standard, NOT HRC or IRC.
TV Won't Tune High Enough to get Modulated Channel
1.Use an external tuner i.e. VCR or a Cable Box converter tuner to allow the TV to view a modulated channel on a channel through the external tuner.
2.If the modulated channel is beyond the capabilities for that TV, the TV will not work with the system.
Cable Company Box Won't Pass a Modulated Signal
1. Connect modulator directly to TV and verify the modulator is sending a signal the TV can receive.
2. Use model 3101 Cable Box Combiner Kit to route the modulated signal around the cable box. See schematic page.
Cable Company Uses All Available Channels
1.Use a low pass filter (3102) to block out channels 80 and above for clean modulation (won't effect channels
2.Call for pricing on a custom filter to block out a specific channel
or multiple channels.
Modulated Picture is Too Bright or Washed Out
1.Adjust the white video level. Adjust port on the
chassis located under the white cover plate above the channel select to the proper brightness.
2.If using a camera, check positioning of the lens to be sure it's not aimed at the sun or a reflection.
3.Adjust camera lens - see lens manual.
Modulated Picture is Too Dark
1.If baseband video is being split with a Stereo Loop Kit or loop through quad, set impedance matching switch or potentiometer
(termination switch) to 1ΚΩ.
2. Adjust the white video level adjust pot on the chassis located under the white cover plate above the channel select to the proper brightness.
3 Check all connectors for 75Ω.
Noise on the Audio
1.Insert grounding block in line and ground coax cable before it enters the TV.
2.Use professional grade audio/video interconnect between the components and the modulator.
O u c h!!!
Audio is Too Low
Use a
Herringbone in Picture on Modulated Channel 
Disconnect modulator from local channels 
an check modulated channel.
A) If there is programming move the modulated channel.
B)If the picture is snowy, use a
to
block noise or data coming in from cable company.
C)Separate modulated channels by two channels.
Horizontal Bars Rolling Through TV Picture
1.Check for a component of the system to introduce DC power into the system. Disconnect that component and check TV. If the hum bars stop, use a DC blocker down stream from that component to block the power from getting to the TVs.
2.If the rolling is only on the modulated channels, check for impedance mismatch by adjusting the video level adjustment pot.
Vertical Bars Rolling Through TV Picture
Check for AC power getting on the line. Use a ground breaker in line.
Black and White Lines on one Local Channel
Move modulated channel up to a new channel. If problem persists and all of the inputs of a multiple input modulator are not being used, check default channels on modulator to see if default channel is set to the same channel that the problem channel is set to.
Flashing at the Top or Middle of TV Picture
1.If flashing is on modulated channels, turn up attenuator/ down gain of modulator.
2.If flashing is on local channels, attenuate output of amplifier.
3.Remove cable TV from system. If flash stops, install filter
Picture is Tearing
Possible impedance problem. Check that impedance switch is set to 75Ω.
Ghosts on the Picture
1.Terminate all unused ports with 75Ω terminator model 2101.
2.Check for low quality combiner in system. Replace with high isolation combiner, HS model combiner.
