Blonder Tongue Interference.
 

Hmm this is strange. Perhaps I'm doing something wrong here.

When I turn on my Blonder Tongue agile modulator in my room, the TV in the living room (which is on digital cable), looses a picture to Weak or No Signal. Cable, not OTA.

The TV lost a picture on clear QAM channel 6.1 (as for the actual frequency I have no idea, because it's a virtual channel number).

The modulator is using UHF channel 27, and is attached directly to the TV's UHF terminals. The TV's VHF terminals are attached directly to the cable line, as shown here: http://img.photobucket.com/albums/v3...gon/cables.jpg

If both are terminated correctly, how is the modulator screwing with the digital cable signal? (Neighbors are seemingly not affected).

I believe that if this set does not have a remote control feature to switch between inputs (cable, antenna), then the cable input and UHF are connected internally and you can only use one or the other.

It's not even a cable input, it's a VHF input, I only get cable channels 2-13.

I thought they should go to the two separate tuners though. Should it not?

I would think if they were connected internally they would just have only one RF input, not 3.. (UHF 300ohm, VHF 300ohm, VHF 75ohm).

You lost me - how are you viewing clear QAM channel 6.1? What is that VHF cable connection? Is it the channel 3 NTSC output of a digital cable box?

Edit - do you mean the connection in your picture is to a separate TV in your bedroom and you are losing the clear QAM on a digital TV in the living room?

The TV in the livingroom is a LCD with clear qam.

The blonder tongue connected to the samsung in my sig, seems to be relaying interfearance to the TV in the livingroom.. I would think the UHF and VHF terminals are separate.

It is still possible that the B-T signal leaks from the UHF input on the Samsung over and out the VHF input on the Samsung and then into the cable input of the LCD, yes. Confirm by disconnecting the VHF input to the Samsung. If the problem goes away on the LCD, you know the cause.

The B-T output is probably much higher than you need for direct input to the TV. Adding an attenuator to the B-T output may fix the problem by reduing the leakage signal.

Issac and Ben... Bring the man a variable attenuator!

Looking at the pix of the back of the set, my guess is that there is considerable leakage of the high output of the B-T from the UHF terminals to the VHF terminals of the set. This signal then is conducted through the coax to the set in the living room.

Same problem as in this thread:

http://www.videokarma.org/showthread.php?t=254632

jr