DC Area issue with 1 VHF Channel

Necromancyr

DTVUSA Jr. Member
#1
What is your primary objective (check the line applicable) :
I don’t want to spend much, just want a few Local Stations:_X_.
I want as many as I can reasonably get:_X__.
I want the best system I can, to replace my Cable/Satellite Service:_X__.

**I need to, at the least, get the major networks. (ABC, NBC, CBS, Fox, WB, CW)

Main Assembly:
What kind of Terrestrial Antenna do you presently have: RCA ANT751

Is the Antenna to be/or installed: Attic (~25 ft, '3rd' floor)
Do you have an Antenna Rotator: No.
Are you presently using a Pre-Amplifier: No.

Interior:

How many linear Cable feet is it between your Antenna and the most far TV: Unknown, but can't receive even on <50ft. (test configuration directly to closest TV, I will amplify the signal if needed once I can get reception on that TV to go to the basement).

How many TV sets will be/are presently being used, on this system: 2-3.

How many Splitters are in use in your system: 0 splitters to test TV (direct connection); final setup after amplifier addition will have between 3-4 dual splits (1 in/2 out) due to insanity in house wiring and a MoCA network setup.

Are you using a Distribution Amplifier: No.

Additional Information:
Are you/do you plan to integrate Cable or Satellite Services with this system: No.

Is there anything else you would like to provide concerning construction, obstructions or geographical issues? It's a townhouse and based on antennaweb and fmfool, the 'direct line of sight' could be through my 'block' - basically 3 houses. I have dense woods behind my house as well, however not in the direction of the towers.

Do you have a current Chart for the Free Local TV Channels in your Area?
TV Fool

All channels except for 7 currently come in (it's just below 25% in the 'strength' bars on my little converter box I'm testing with). If the antenna is pointed just right, 2.1 (38), the ABC affiliate in Baltimore, will actually come in but with constant breakup and pixelation. I think this is basically the signal coming in from the back/side of the antenna setup because when I move the antenna from a certain direction, it gets completely lost.

I guess the big questions are will a preamp do anything to boost this 'marginal' signal...(I'm thinking no)...and do I have any other options? I can't get onto my roof (long story involving the small size of a town house together with my current unwillingness to drill through my roof to install the antenna! :) ) so an internal antenna is my only real option. Using a pole from out back wouldn't work because of the woods I think.

Thanks in advance for any help/advice anyone can give.
 

Aaron62

Contributor
Staff member
#2
Wow, not sure how much I can help you out, but you've sure provided a lot of details for a first time poster! Welcome to the forum. I'm thinking that a preamp may actually help you since the distance between your TV and antenna is about 25'. I'll step aside and let the pros speak up. ;)
 
#3
Nice job of supplying details!

Your problem isn't signal power on WJLA since WUSA operates from the same tower and at the same power and your report indicates no problem with channel 9, it's either interference (possibly from FM radio) or multi-path. As you have two 50 Kw FM stations almost due south of you in the 88-90 MHz range, I'd lean towards attacking that first by adding an FM filter rather than an amplifier.

FM filters come in two varieties- Those that attempt to preserve RF channel 6 (by gradually sloping into the lower part of the FM band) and those that don't. You need the latter type. Antennas Direct has an inexpensive filter ($about 4 bucks plus shipping) that whacks the WHOLE FM band by at least 20 dB. The now-discontinued Radio Shack FM trap (available on ebay) is the former type and wouldn't help enough.

I would specifically avoid a pre-amp due to probability of overload. A modest distribution amp might be needed.
 
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Necromancyr

DTVUSA Jr. Member
#4
Nice job of supplying details!

Your problem isn't signal power on WJLA, it's either interference (possibly from FM radio) or multi-path. As you have two 50 Kw FM stations almost due south of you in the 88-90 MHz range, I'd lean towards attacking that first by adding an FM filter rather than an amplifier...
...I would specifically avoid a pre-amp due to probability of overload. A modest distribution amp might be needed.
Glad I could supply enough details! I did forget one thing. I have a friend that lives nearby and he CAN get WJLA with an amplified indoor antenna, but he said it's a pain in the ass and his wife generally leaves the room when he tries.

And - :mad: - more waiting for something to come in the mail. Wanted to get rid of cable as fast as possible (dropping my landline today from FiOS and would LOVE to just drop cable as well).

....hrm. Just $4 and $9 shipping :huh: - that's ridiculous for something so small. Would Best Buy or RadioShack have something like this in their brick and mortar stores? (Not seeing anything via quick search on their websites)
 
#5
Nice job of supplying details!

Your problem isn't signal power on WJLA since WUSA operates from the same tower and at the same power and your report indicates no problem with channel 9, it's either interference (possibly from FM radio) or multi-path. As you have two 50 Kw FM stations almost due south of you in the 88-90 MHz range, I'd lean towards attacking that first by adding an FM filter rather than an amplifier.

FM filters come in two varieties- Those that attempt to preserve RF channel 6 (by gradually sloping into the lower part of the FM band) and those that don't. You need the latter type. Antennas Direct has an inexpensive filter ($about 4 bucks plus shipping) that whacks the WHOLE FM band by at least 20 dB. The now-discontinued Radio Shack FM trap (available on ebay) is the former type and wouldn't help enough.
I second the motion to whack the whole FM band. I suspect that WAMU and WPFW are causing second harmonics in the receiver.

If you can't find the Antennacraft FM filter, you can also use an HLSJ to filter out FM and low band VHF.

Pico Macom HLSJ VHF Band High-Low Antenna Separator-Combiner (HLSJ) - Pico Macom - HLSJ -
 
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Necromancyr

DTVUSA Jr. Member
#6
Interesting. I'm hitting Home Depot later today (it's a replace your phone and tv weekend...along with plant a bunch of plants, hang a kids swing outside, work my butt off weekend) and I'm going to check if they happen to have something like this there as well.

Few quick clarifications - will ANY VHF antenna separator/combiner work? And I'm guessing that I just plug the antenna into the high and then the out, leaving the low empty?

For the filter, if I see something in a store any particular wording/language I should look for if there's not a graph on the box?
 

Don_M

DTVUSA Member
#7
... will ANY VHF antenna separator/combiner work? And I'm guessing that I just plug the antenna into the high and then the out, leaving the low empty?
Connect the antenna to Line and hook up the TV downlead to Hi. For best results, attach a coaxial terminator to the Lo connector. This will prevent reception-sapping signal reflections from reaching the TVs.

For the filter, if I see something in a store any particular wording/language I should look for if there's not a graph on the box?
Study the wording for the HLSJ at the link provided above for clues, but don't be surprised if you don't find much more than basic splitters at the big-box stores. That's the way our home centers are out here, anyway.
 
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FOX TV

Contributor
#9
I agree that it is most likely the FM interference issue referenced in previous posts. An FM trap or filter may go a long way in solving this problem. Analog TV sets of the past actually had FM filtering built in them in order to be able to claim FCC part 15 compliance, but somewhere in the digital conversion process, the FCC did not require it for the digital boxes to conform to FCC part 15 regulations for FM filtering. FCC part 15 set minimum interference standards for receivers, transmitters etc, and it's purpose was to minimize interference to other devices.
 
#10
For the filter, if I see something in a store any particular wording/language I should look for if there's not a graph on the box?
I don't know of any retail locations selling the HLSJ in the DC area. You can order them online for less than $5.00 plus shipping. If you want to try one first, I have one you can test with. I work near the World Bank on K Street.
 

Necromancyr

DTVUSA Jr. Member
#11
Hrm...that brings up an interesting question. Would a VCR have an FM trap in it? Can I run the antenna feed through an older VCR, then to the converter box via the passthrough/line out to test it? Or...maybe tune the VCR to channel 7 then use the pass through from there to the converter...

Hrm.....thoughts?

(And the guy I mentioned above with the inside amp'd antenna has said he'd go in on an order of 2 of the traps for me since it's so cheap and might reduce his hassle with the channel - so the price isn't as bad for the 2 of them...will order if I can't test this out using the VCR some oddball way...)
 

Necromancyr

DTVUSA Jr. Member
#13
Package came today and I promptly hooked it up.

Channel 7 is now coming in semi-clear - the signal seems to waver a bit sometimes, and pixelate for some unknown reason. Might be a time of day thing, as it seems to have stabilized and gotten stronger in the last 2 hours. Also, I connected the cable down to my basement and the tuner on that tv seems to pick everything up even better than the converter box I have in the bedroom on my SD TV (and that's like...2-3x as much cabling AND with a splitter in the middle that's -3.5db per tap).

So - thank you guys!

Only problem...one of the filters I ordered had the back popped off when it got here. Need to get a replacement since it's for someone else! Hopefully Antennas Direct is quick about it.
 

Necromancyr

DTVUSA Jr. Member
#14
Antenna's direct is sending 2 more out immediately. - great customer service. Although, seeing what's inside one of these, I realize why sending out 2 more isn't a big deal! :)
 

Aaron62

Contributor
Staff member
#15
Antenna's direct is sending 2 more out immediately. - great customer service. Although, seeing what's inside one of these, I realize why sending out 2 more isn't a big deal! :)
hehe I know, some of the costlier filters, antennas, and preamps look like they should sell for half the price, but a lot of the cost goes toward research and development.
 

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