High VHF help NE of Detroit

Daddylion · 1-Aug-2013, 6:40 PM

I thought I had it figured out but the high VHF (7 and 14) are giving me trouble. One of the channels is Fox so it's messing with football.

http://www.tvfool.com/?option=com_wr...46aee145821d12

I currently have an RCA ANT751R http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

with RCA TVPRAMP1R preamp http://www.amazon.com/RCA-TVPRAMP1R-...d_bxgy_e_img_y

They are mounted just below the peak at the back of my house. I have large maple trees in my back yard and there is no way to get around them and to go over them I'd need to put a 50 foot mast on top of the roof so that's not an option.

I'm only interested in the top 10 channels on the report. They are all between 250 and 257 degrees. The main issue I'm having is with the high VHF channels 7 and 14 about 40 miles away (FOX and CW). The other channels near the top of the list all come in pretty well.
I am only going to two TV's.
50 feet of coax from antenna to a splitter and 25 more to each TV.

Thank you so much for your help.

GroundUrMast · 1-Aug-2013, 6:58 PM

Have you tried running with no preamplifier? (All parts of it removed from the system.)

If you have already tried moving the ANT-751 to all possible locations, you may need to consider going up to a larger, higher gain antenna.

Given that you are forced to aim though vegetation, a Winegard HD7694P or Antennacraft HBU-33 would not be overkill... even the larger versions of those designs would be worth considering.

1-Aug-2013, 11:32 PM

Even if can not get above the tree , Higher Is Still Better.

Install a bigger antenna , install a Winegard HD7698P antenna.

Aim the HD7698P antenna at about , 261 degree magnetic compass direction.

Here is how to aim antennas , http://www.kyes.com/antenna/pointing/pointing.html.

Here are some above the roof antenna mounts.

http://www.ronard.com/909911.html.
Use the , ronard(911) 5 foot antenna mount.

http://www.ronard.com/Tripods%200703/4712.html.

http://www.ronard.com/ychim.html.
Measure the Chimney and use a , ronard(2212) , ronard(2218) , ronard(2224).

Buy the ronard antenna mounts at solidsignal by typing , ronard(x) , in the solidsignal search box or by from ronard.

Here are some places to buy antennas and etc. .

http://www.solidsignal.com.

http://www.amazon.com.

http://www.winegarddirect.com.

http://www.ronard.com.

________________

Test reception without and with the preamplifier.

When Test reception without the amplifier , Disconect and Remove All Parts of the amplifier , the preamplifier unit , the power injector , the power supply.

_________________________________________

Look for a way to install the HD7698P antenna at a location that is not blocked by the tree/s the direction of reception.

Or has the Least amount of tree/s obstructing reception.

___________________________________________________

Digital Tv Tuners can develop - Digital Glitches - that are not cleared out with simple channel scans.

Do Double Rescan , http://www.dtv.gov/rescan.html.

Daddylion · 2-Aug-2013, 12:56 AM

When I remove the preamp I can get Fox (channel 7 / 2.1) at 45-50 strength, but every other channel loses between 40 and 50 or disappears completely.

W/out preamp:strength
Ch 7 45-50
Ch 21 20-25
Ch 41 30-40
Ch 43 0-15
Ch 45 45-55

W/ preamp
Ch 7 0
Ch 14 55-60
Ch 21 70-75
Ch 28 20-25
Ch 29 85-90
Ch 39 55-60
Ch 41 75-80
Ch 43 45-50
Ch 44 50-55
Ch 45 75-80
Ch 50 60-70
Ch 51 30-35

I'm new to this, but why would the preamp "kill" one weak channel (7) while helping all the others?

GroundUrMast · 2-Aug-2013, 1:13 AM

All amplifiers add some noise to the signal and distort the signal to some degree during normal operation. If overloaded, they will produce far more distortion. The TVPRAMP1R is not known for be able to handle strong input signals. If the overload is not extreme, the distortion may impact a few channels.

You may need to move to a high input preamp such as the Winegard HDP-269.

No static at all · 2-Aug-2013, 2:23 AM

Is the pre-amp set to combine? Is the FM trap in the on position?

I would also try installing a Radio Shack FM trap between the amp & antenna. You have a 250 watt FM station right in town (91.3). The internal trap of that amp does not effectively attenuate FM stations below 95Mhz.

No static at all · 2-Aug-2013, 11:10 AM

Upon closer examination, the FM trap & combined settings are the default from the factory, but you can double check them to make sure.

The fact that channel 7 completely disappears makes me lean towards FM 91.3 being the culprit. You won't know till you try adding the RS FM trap before the amp input. You can return the trap to Radio Shack if it doesn't help.

Daddylion · 2-Aug-2013, 8:20 PM

Quote:

Originally Posted by No static at all

Upon closer examination, the FM trap & combined settings are the default from the factory, but you can double check them to make sure.

The fact that channel 7 completely disappears makes me lean towards FM 91.3 being the culprit. You won't know till you try adding the RS FM trap before the amp input. You can return the trap to Radio Shack if it doesn't help.

The FM filter didn't seem to help, and now every channel wildly fluctuates. Channels that were stable yesterday now drop out completely for a few seconds and then come back. I will have 70 or 80 one second and 0 the next. This continued after I removed the FM filter and the preamp.

GroundUrMast · 2-Aug-2013, 8:53 PM

Just to be sure... The Radio Shack FM trap (filter) was installed between the antenna and outdoor section of the preamplifier... ?

If yes, you are getting to the point where you need to consider trying an antenna with more gain and narrower forward beam. This would very possibly eliminate the need for amplifier gain which would eliminate the noise and distortion produced by a powered amplifier. You would also be reducing the relative amount of multi-path interference received.

I'm quite happy to agree with the HD7698P recommendation made by @teleview

Daddylion · 2-Aug-2013, 9:05 PM

Yes, the FM trap was between the antenna and the preamp outside.

My confusion is with the fact that yesterday the signals were stable with and without the preamp, but today all channels bounce to zero several times per minute. Would a new antenna help with that?

GroundUrMast · 2-Aug-2013, 9:44 PM

Is there a bit of wind moving the trees today... more than yesterday? When aiming through trees, wind causes poor reception by creating fluctuating signal at the antenna. The symptoms would be as you describe.

As you disconnect and reconnect cables, it's possible that the contacts inside one or more connectors has spread and is no longer making reliable contact

Daddylion · 4-Aug-2013, 12:02 PM

Quote:

Originally Posted by GroundUrMast

Is there a bit of wind moving the trees today... more than yesterday? When aiming through trees, wind causes poor reception by creating fluctuating signal at the antenna. The symptoms would be as you describe.

I've found a vent on my roof that has a clear view through the first layer of maple trees. The first tress from this vent are about 100 ft away.

I'm going to try these clamps
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

and attach the antenna to this mast
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

Quote:

Originally Posted by GroundUrMast

As you disconnect and reconnect cables, it's possible that the contacts inside one or more connectors has spread and is no longer making reliable contact

The patch cables I have at the antenna are not high quality (they are the slip-on type) so I ordered a couple of these to try out with the preamp and FM trap.
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

From what everyone has been saying it sounds ideal to have an antenna strong enough to be used with no preamp, but if I have to use a preamp I may need a higher quality preamp.

If the new mounting location doesn't help which would you try first?

Stronger antenna (Winegard HD7698P replacing RCA ANT751R)
Higher quality preamp (Winegard HDP-269 replacing RCA TVPRAMP1R)

The journey continues...

No static at all · 7-Aug-2013, 11:21 AM

A better antenna would be my next move. There is nothing wrong with the amp you have. It handles strong signals remarkably well & has relatively low noise.

I would never suggest the HDP-269 unless used with an attic/indoor antenna. The HDP-269 is too sensitive to static buildup & more prone to failure than any other amp from my experience/research. The HDP is over-rated/over-recommended & there are many better choices for strong signal environments.

7-Aug-2013, 5:41 PM

Coax that is exposed to , Weather / Water.

Use RG6 Coax that has the Compression Type Connectors on the ends of the coax.

Not the old crip type connectors.

Not other cheap flimsy coax and connectors.

To make Double Sure that , Weather / Water , does not get into outside connections.

Remove and Discard Rubber Weather Boots , rubber weather boots take in water and hold the water inside the boots , this is not good for connections.

Wrap outside connections with , http://www.coaxseal.com.

GroundUrMast · 9-Aug-2013, 7:34 AM

Quote:

Originally Posted by No static at all

A better antenna would be my next move. There is nothing wrong with the amp you have. It handles strong signals remarkably well & has relatively low noise.

I would never suggest the HDP-269 unless used with an attic/indoor antenna. The HDP-269 is too sensitive to static buildup & more prone to failure than any other amp from my experience/research. The HDP is over-rated/over-recommended & there are many better choices for strong signal environments.

Thanks for pointing out the problems with the HDP-269.

Given the discontinuation of the Antennas Direct CPA-19, can you suggest a high-input preamp that is not as tender to ESD damage?

Cheers

No static at all · 9-Aug-2013, 10:57 AM

Quote:

Originally Posted by GroundUrMast

Given the discontinuation of the Antennas Direct CPA-19, can you suggest a high-input preamp that is not as tender to ESD damage?

Cheers

Sure, for the highest input tolerance, you can't beat the Channel Master/PCT 34XX series distribution amps. They can also be used just like a pre-amp with the optional remote power supply.

The Antennacraft 10G201 & RCA PRAMPR1 are good choices too, although the RCA hasn't been around long enough to predict reliability. Another member here (Pete Higgins) has just tested the RCA at his location & it seems to be just as tolerant as the Channel Master distribution units with screeching input levels. The dual input capability of the RCA is a nice feature as well.