I am having problems with the OnQ modulator that I just installed. Inputs from Satellite Dish Receiver are coming into the modulator which is set on channel 120. Modulator's RF output is connected to OnQ 3x8 enhanced video module's auxiliary input, which also has cable coming into it.

When the room TV is turned on to channel 120, the Satellite picture is seen, but strong static lines are all over it. Also, TV outputs a high noise and disturbance. In another room's TV, only th epicture is seen with same disturbance and static, but no noise. Low pass filter is also connected to the OnQ 3x8 module before cable comes into OnQ. I tried with and without the low pass filter - same result.

Can someone help me with solving this problem. What could be wrong? Could 50 feet wire run be the problem?

It may be of note - that when I installed the modulator, the power supply was bad. I had an old power supply with same specs (except this one used 100mA of current as opposed to 200mA on the one that came with modulator). I don't know if this has anything to do with it (I wouldn't think so).

Thanks

I have three 4 port modulators right now combined with cable. My modulators outputs all go into a modulator combiner and then go into a 2 way combiner along with my cable feed which has a low pass filter on it. Out of the combiner I go to a 3 way splitter which goes to three 1x6 distribution amps. When first installed I had some real problems but installed an attenuator before the modulator signals when to the combiner. I bought the kind you can control with a dial and my picture is now perfect.

The power supplies supplied with ALL products are supplied for a reason! The difference between 100Ma and 200Ma may seem like nothing to you...but it may seem like the difference between a 120VAC current and a 220VAC current to your new Maytag Clothes Dryer...

also, why channel 120...you may be the FIRST integrator I can remember that's used a channel that high! Do ALL TV's support that channel without chagind the settings? STD, IRC, HIRC, etc... are all different option you may have to choose from on a TV, not including CATV....blah...blah...blah...

send (and post) more info

avdude

???

We always start in the 120's, have for years. Lately I've been routinely adding an low pass filter tuned to above Ch 116 to allow the two-way cable boxes to work. In any event, we got tired of setting these modulated sources in the 80's only to have the client call with a "The cable company added some channels, and now the whole-house sat picture is fuzzy..." Now we start at the top and work down.

I have not seen a television in years that asked me to select STD, HRC or IRC; I suppose it's automatically selected. My cable meter is not so smart, and needs to be told.

Yes, that is actually what I feel as well and therefore prefer channels 118 and above. In addition, I was told that if you have (or change to) digital cable later, it is better to modulate on channels above 117, gives you better performance.

Anyway, any suggestions out there for my problem?

Thanks

Ok first off I happen to agree with avdude and wonder why 120. However instead of trying diagnose the result do yourself a favor and isolate the cause. Leave the system as it currently is and take the cable feed out of the system. More than likely you will see the distributed Sat signal immediately get better. I would assume that there is digital cable in the area you are which means even though you may not be using a set top cable the channels are actually still in use or reserved. Either way you say you are using a filter for Ch116 is that a choke for 116 and above? Isolate its actual trap frequencies and go from there channel vision has good documentation to help you there. Ok other possible areas of concern would be the way you have this setup at the head end this is based on what I think you are saying. Anyway the cable signal coming in at the board lets say for sake of argument is 15db which trust me it isn't. Then you are modulating a Sat to 120 running at 25-30db trust me it is then on top of that you are amplifying it once again after it comes back out of the combiner. Try either using an attenuator possibly in the sat signal or maybe combine the sat signal after the amps. Best thing I can off is start at the beginning rahter than the end because that is where the problem is. Hope this helps and if I am way the hell off all I can say is I need more info!

I have to start at 120 these days, i can't get a worth while picture when combining with cable lower than that. Plus I hate to have to go rearrange the modulated channels when the cable company decides to change their ordering. I then have to modify the modulator settings, reprogram remotes, and reteach clients. Sometimes I do get older tv's that can't go that high, i just show the client what it would look like if I place the signal on channel 80 or so and they agree, put it on 120 and they will get a new tv.

As for the origin of this thread, I find most modulator picture problems come from over amplified signals, they get juiced up in the modulator, then sent through amps, then run thirty feet and are way to hot. Try hooking the ouput directly to one RG6 directly to the tv, see if you have a decent picture, and then add you cable signal, amps etc, until you discover which piece is causing the problem.

AVdude had a good point. I spoke with OnQ tech support and they also suggested to first put the correct power supply. I have ordered the right power supply. As soon as I receive it I will replace it and if the problem still persists, we will have to go from there. Will keep you posted.
Thanks

Sounds a LOT like a bad low pass filter.

Had a job recently where the filter went south, and the picture quality was exactly as you descibe.

The only right way to check this is by using a field strength meter (Leader), or some other form of meter, to determine if there's anything still residing on those "supposedly" empty channels.

Trunk-Slammer -Supreme:

Good point. I will try this as well after the new power supply is installed.

Thanks

Why do you have to modulate the signal?

The reason to modulate the signal is so that cable, satellite, DVD, VCR etc can be monitored in multi-room A/V installtion at different channels at the same time. Without modulation, it would be difficult to switch from satellite to cable TV without having to switch off the satellite receiver. Remember, there is only one RF (RG-6) wire running to each TV from the central location in the basement.

ahh...oversight or just what you got stuck with?