Help with Mississippi fringe reception

[Tonye]

An ad was covering part of my tv fool report link so I am resorting to gps coordinates. Longitude is 31.414528361212895
Latitude is -90.71208437387997. It looks like I have no chance of getting ABC. This would be a new setup from scratch so comments or antenna advice would be appreciated.

[rabbit73]

Welcome to the forum, Tonye:

These are tvfool reports at different heights using your coordinates:

no height specified:
http://www.tvfool.com/?option=com_wr...f1f00a6311e7b6

25 ft:
http://www.tvfool.com/?option=com_wr...f1f08263c6b640

50 ft:
http://www.tvfool.com/?option=com_wr...f1f05434a3d41c

75 ft:
http://www.tvfool.com/?option=com_wr...f1f04314f4113f

100 ft:
http://www.tvfool.com/?option=com_wr...f1f06755bbc3af

If my results match your tvfool report, you may want to delete your coordinates from your post to protect your location.

I first entered your coordinates here using the interactive map feature of tvfool and saw in the aerial view that you had enough room for a tower in hopes that if your antenna was high enough you might have a chance for ABC:
http://www.tvfool.com/index.php?opti...pper&Itemid=90

It looks like you would need at least 75 feet for a fairly good chance at ABC with a high gain antenna, considering it is a Tropo signal. You would also need a preamp, but your strongest signal WMAU-DT on real UHF channel 18 would probably overload the preamp. That would require a custom single channel bandstop filter for channel 18 to weaken WMAU-DT. How badly do you want ABC?

Even if you were willing to do without ABC, you would still need the Tin Lee custom filter to get the other channels.
http://www.tinlee.com/MATV-Bandstops.php?active=3#CR7

Call them first and talk to their engineer and email your tvfool and FM Fool reports, and a link to this thread to him.

I would suggest a Winegard HD7698P antenna and an Antennas Direct Juice preamp. You would also need an FM trap/filter to weaken the very strong WMAU-FM:



Disclaimer:
Your situation is very difficult; no guarantees.

[Tonye]

Thanks for the analysis. If ABC is a long shot without 75 foot tower, how high of a tower for the other stations? Is the AD91XG directional enough to ignore WMAU?

[Tonye]

Is fm trap and single band filter the same thing?

[rabbit73]

Thanks for the analysis. If ABC is a long shot without 75 foot tower, how high of a tower for the other stations?

You might be able to get away with 25 ft. if Fox with a Noise Margin (NM) of -3.8 dB is your weakest desired signal.

Is the AD91XG directional enough to ignore WMAU?

The 91XG is an excellent choice for UHF, but it is not suitable for CBS on VHF-high real channel 12. If you used the 91XG, you would need to add a VHF-high antenna combined with the 91XG using a UVSJ (UHF-VHF Splitter Joiner).

The 91XG is very directional, and WMAU-DT is in the opposite direction, but I don't think that the F/B (Front to Back) ratio of the 91XG is enough to ignore WMAU-DT. You would still need the custom single channel bandstop filter for channel 18 from Tin Lee. The filter would be inserted between the antenna and the input of the preamp. The filter doesn't need to have enough attenuation to completely eliminate CH 18, just enough to weaken it so that the preamp isn't overloaded; the AD Juice preamp is stated to be highly resistant to overload. Without the filter, WMAU-DT is 81.2 dB stronger than Fox.
Antennas Direct 91XG Antenna Technical Data Sheet
JUICE Amplifier System

Since your reception problem is very difficult, it would be a good idea for forum member ADTech to double check my analysis. He works for Antennas Direct and often comes here to give excellent advice. If he doesn't show up to post his advice for your problem, I suggest that you send a PM to him to get his attention.

[ADTech]

The signal from WMAU will be substantially less than the calculated amount since the simulator does not include the vertical (elevation) pattern of the transmitting antenna. Most likely, at this depressed elevation of about 3.4°, the RMS field strength will be about a quarter of the main lobe's strength which is probably 800' above the rooftop at this location. Off the cuff, that means that the signal power is probably 10-20 dB below the forecasted level.

Either the DB8e or the 91XG will suppress the signal from the rear by about 10 (or more) dB. Combined with the lower power due to the depressed angle, that should weaken WMAU by 20-30 dB which may make a bandstop filter unnecessary.

I'd try the DB8e with a Juice pre-amp. I'd also hold off on the VHF antenna, you may not need it for your single VHF station from Jackson and it can, if needed, be added later.

[rabbit73]

Is fm trap and single band filter the same thing?

Yes, if you mean FM Band Rejection Filter. The FM trap/filter is to weaken WMAU-FM which is, at -7.4 dBm signal strength, a threat to the reception of CBS on channel 12. The Juice preamp does not have an internal FM filter, so you would need to add one or two in series with the CH 18 bandstop filter between the antenna and the input to the preamp.
Juice amplifier specs
AD FM Band Rejection Filter

Some other preamps do have an internal FM band rejection filter, like the CM 7778, but they are probably not as resistant to overload as the Juice.

A good alternative to an FM band rejection filter is a HLSJ (VHF-High-VHF-Low-Separator-Joiner) which attenuates everything below CH 7, including the FM band, by 25 dB. It has a low insertion loss because it uses a high-pass filter between the high and common ports.
Holland HLSJ

The coax should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.

[ADTech]

Yes, do include an FM filter. The Juice likely won't overload, but your tuner probably will.