Preamplifier Advice

[Durathump]

I recently mounted a Antennas Direct DB4 antenna on the roof of my house. I aimed it at 49° since the stations that we are interested in are between 20° and 78°. My signal analysis: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d0b8679f8ced9c6

The signal is 90 to 100% on all channels except for the VHF channel 10.1 which varies usually between 45 to 55% and sometimes goes to "no signal". This channel is unfortunately the one that we view the most.

To get these results, I have the antenna directly connected to the TV with a cable going through a window. Previously I had disconnected the cable service input signal cable and connected my antenna through the cable system going into the house. The signal was much lower on all channels when I did this.

I'm considering getting the Winegard AP8800 since it's db level for VHF is higher than for UHF which seems to be what I am needing.

Also I was wondering if I should use the existing cable service in-house system or scrap it and run a new setup. I want to supply 2 TV's at this time but might expand that to a total of 4 later.

The longest run between the antenna and TV will be around 75 feet.

I thought I'd consult the professionals to see if I'm think in the right direction.

Thanks in advance.

[GroundUrMast]

The DB4 is a very good UHF antenna but it's not intended to function well in the VHF band. Real channel 10 will be received more reliably if you add a high-VHF antenna such as the Antennacraft Y5713 (http://www.antennacraft.net/Antennas/AntennasVHF.html). You would need a UVSJ (http://www.solidsignal.com/pview.asp?p=UVSJ&d=Pico-Macom-UVSJ-UHF-VHF-Band-Separator%2FCombiner-for-Antenna-%28UVSJ%29) to combine the signals from the UHF and VHF antennas into a common down-lead.

I'll recommend against the AP8800 in your case. The AP8800 is a 'fringe' or 'deep fringe' amplifier. It is designed for locations with weak signal levels. The strong signals in your area are likely going to overload an amplifier of this type.

I don't believe you will need an amplifier to drive four sets, but a high input amplifier can be added later if it proves necessary. Pre-amplifiers such as the Antennas Direct CPA-19 and Winegard HDP-269, or distribution amplifiers such as the Channel Master CM-3410 and CM-3414 would be viable options.

[Electron]

Install a AntennasDirect ClearStream 5 aimed at about 69 degree magnetic compass for reception of channel 10. Combine the CS5 and the DB4 with a UHF/VHF combiner that has a weather protected housing. http://antennasdirect.com

[Electron]

The tv transmissions are Strong. A preamplifier Will Not be needed , A preamplifier will overload and be the cause of bad reception or no reception. The 2 antennas of DB4 and CS5 should provide signal for 1 to 4 tv sets.

[Durathump]

Thank you for the information!

Can these antennas be mounted to the same mast and if so how should they be spaced?

[Electron]

Yes the CS5 below and DB4 about 2 feet above on the same mast. And can also be mounted on separate masts. . Here are some Strong and Sturdy antenna mounts , http://www.ronard.com/909911.html , http://www.ronard.com/34424560.html , http://www.www.ronard.com/ychim.html , http://www.ronard.com

[ADTech]

A C2v would have been a better choice for your location, but, since you already have a DB4, you shouldn't need to invest in a C5 to get KOLR from the south side of Springfield.

A reasonably handy person can get one of our C2 VHF reflector kits (Shop Now > Accessories > Reflectors), take it apart, and "re-purpose" its components onto a DB4 (or any of our bow-ties or loop antennas). I'd pick up a couple of 1.5 - 2" #10 screws from the hardware store or junk drawer first. Mount the dipole to the inside of the one of the mast clamp screw positions (use longer screw). Mount the diplexer via one of the open holes below the mast clamp. Tilt it a bit to one side so the coaxial cable can be attached.

Viola! A DB4v...

Aim it towards Fordland and cheat it a bit northward to pick up KRBK (tower is north of Lebanon).

[Durathump]

Thanks for the detailed information! I greatly appreciate the time spent analyzing my challenge and the suggestions offered.

[Durathump]

I ordered the C2 VHF reflector kit from Antennas Direct. I removed the dipole, wiring and diplexer from the reflector assembly. I attached the dipole to the DB4 by using an existing unused hole in the upper part of the antenna. It fit perfectly in the wider spaced grid on the upper reflector. I attached the adapter to the aluminum beam with a wire tie. I routed the cable down and attached the diplexer in another unused hole at the lower part of the aluminum beam. I was able to use the bolts from the c2 kit also. The only thing that wasn't supplied was the wire tie. This was a very simple modification.

My signal strength of the VHF station that I was wanting to improve reception of is now steady at 95%. Previously it was 45 to 55% and sometimes had no signal. The other stations which are UHF were unaffected and strong.

I removed the direct connection to my TV from the antenna and connected it to cable network system in the house and lost very little strength.

http://i842.photobucket.com/albums/zz345/sawnami/Antenna%20Modification/Antenna1.jpg

http://i842.photobucket.com/albums/zz345/sawnami/Antenna%20Modification/Antenna2.jpg

[ADTech]

Thanks for sharing your results! Glad it worked out well for you.

By the way, how is KRBK working out (Fox)?

[Durathump]

Thanks for sharing your results! Glad it worked out well for you.

By the way, how is KRBK working out (Fox)?

KRBK is a steady 97%. I am completely satisfied with my antenna performance.

[gawellman]

Just wanted to say thanks for sharing your experience with adding the dipole to a DB4.

Needing to pull channels 5, 11, 27, and 38, I initially tried a C2V, but the signal on 27 was marginal. Some Google searching led me here, and I put together a DB4e and the dipole from the C2 VHF reflector kit. Works a treat!

http://i41.tinypic.com/2gvlt1w.jpg

[Durathump]

Glad to know that the information helped. Mine continues to work flawlessly.