FM Trap or FM Trap/amplifier understanding?
 

So I guess I am trying to understand the FM Trap/amplifier combo. Does the FM Trap/amplifiers that are sold suppose to trap the FM signal and amplify all signals outside of the FM?
So if I have a situation like this "This means that any very strong FM signals between 102 and 105MHz can potentially interfere with channel 12 (102*2=204, 105*2=210)." with a FM Trap/ amplifier will trap the FM signal and amplify Channel 12?

All the traps I see do not seem to be able to be tuned. Winegard made the FT7600 FM Trap which was tunable but has been discontinued. Is that because it is unnecessary to be tunable or is it one of those things that was better and has disappeared?

Personally I am talking about trying to increase my signal strength NBC /KNTV channel 12 off of San Bruno but I live very close to Sutro Tower in San Francisco. I am using Antennas Direct C5 ClearStream 5 High Gain Digital VHF Antenna. HDHomeRun signal strength is in the 55-59% range for the NBC channel.

Thanks

A tuneable trap is not necessary unless you have an extremely strong FM signal to deal with. A Radio Shack FM trap will do the trick for most FM issues unless closer than 2 miles or if the offending signal(s) are between 88-92 Mhz.

If you will provide a tvfool radar plot and channel list report , a better evaluation of the reception situation can happen.

Make the antenna height above ground , 25 feet.

25 feet antenna height above ground is a antenna height that provides a good evaluation of what is receivable and locations of the transmitters.

Use your Exact address to make tvfool report.

While signal strength is important, the signal quality is even more so. Given that you already own the HDHR, use it to measure and maximize your signal quality.

The goal of any FM trap is to keep FM signal(s) from entering active components such as preamplifiers and tuners. No tuner or amplifier is perfect, they will mix and distort signals to some degree. The problem is worse when signals are strong. By keeping the FM signal from getting to the amplifier, you prevent the FM signal from being mixed with other signals and/or being distorted, both of which would produce interfering signals that would cause the tuner difficulty.

FM Trap and amplifiers
 

The link to my report

http://www.tvfool.com/?option=com_wr...2df9ec131a62a7

Thanks Groundmaster for the FM trap before the amplifier comment.

So I had my system dialed in pretty well as DVRand most TVs could get NBC. I added HDHomeRun to the system but its tuners can't pick up the NBC channel. I have an older TV that can't either. So I am more motivated to see if I can dial it in better. The antenna is off the ground over 25 feet attached near the roof of a 3 story house. I am a little worried about using an amplifier as the KGO strength comes in really strong like 100 % on HDHomeRun tuner scan even with the antenna not pointed in its direction. NBC channel 12 only comes in at 55-59% strength and HDHomeRun support says it needs to come in at > 60% for the tuners.

I am not sure why their tuners can't get it now because I have a media center with a Hauppauge Win TV-HVR 2250 which picks up the NBC channels fine. In WMC it is 4 orange bars but the picture comes in fine.

The 4 orange bars in WMC tell me the signal is kind weak. I plan on play with antenna direction a little more but is there something else I could do to strengthen the NBC channel signal. FM trap followed by a amplifier?

Right now from the antenna to the HDHome Run and the media center there is about 25 foot run with 3 splitters.

Thanks,
Mark

Your TVFR 'screams', "Don't use any amplification, the signal levels are already way too high."

My experience with both models, the older HDHR-US and the current HDHR3-US, has been that they are neither the best nor the worst tuners in the house, both seem to have equal if not identical tuners. If I can make an HDHR happy with a signal, I've got things close enough to make the majority of my other tuners happy.

Given that you are almost next door to the Sutro Tower complex, KGO and the rest of the TV and FM signals are extremely powerful... far to powerful to consider the use of any traditional amplification. The best idea I can think of would be an Antennacraft Y10713 pointed at the KNTV tower. The idea being that the Y10713 is more directional than any other consumer grade H-VHF antenna, this would reduce the nearly 40 dB difference in signal levels between KGO and KNTV, both of which are broadcast on H-VHF channels. Combine the H-VHF antenna with the existing antenna through a UVSJ (UHF/VHF signal combiner).