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post #1 of 49 Old 04-06-2007, 09:26 PM - Thread Starter
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I have searched the forum and could not find this topic.. If there is a topic such as this one please point me in the correct direction..

I am seeking a coaxial cable UHF notch filter which is either tunable or pre-set for the following channels to allow me to insert a clean modulated signal in my home video distribution system.

I need to keep UHF channel 19 (501.25 MHz) & 21 (513.25 MHz) OPEN and CLEAR for a local digital TV station KWCH-12.1/2 / KAKE-10.1
But would like to find a notch filter that will knock down by even if it is as little as 10% any signals on UHF 17 (489.25 MHz), 20 (507.25 MHz) and 22 (519.25 MHz)
Also would like to open up, UHF 43 -( 645.25 MHz) & UHF Channel 53 -> UP (705.25->900 MHz)

Also due to the fact that one set of my UHF modulators are in another room I would like to have a stop filter that would stop any and all VHF & UHF signals below UHF 48 but allow any signals above UHF 49 to pass.. I think that this would be called a HIGH PASS filter

Due to the number of local UHF and now Digital stations in my market.. finding open UHF signals has been very tough!

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post #2 of 49 Old 04-06-2007, 10:06 PM
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Quote:
Originally Posted by DavidEC View Post

I have searched the forum and could not find this topic.. If there is a topic such as this one please point me in the correct direction..

I am seeking a coaxial cable UHF notch filter which is either tunable or pre-set for the following channels to allow me to insert a clean modulated signal in my home video distribution system.

I need to keep UHF channel 19 (501.25 MHz) & 21 (513.25 MHz) OPEN and CLEAR for a local digital TV station KWCH-12.1/2 / KAKE-10.1
But would like to find a notch filter that will knock down by even if it is as little as 10% any signals on UHF 17 (489.25 MHz), 20 (507.25 MHz) and 22 (519.25 MHz)
Also would like to open up, UHF 43 -( 645.25 MHz) & UHF Channel 53 -> UP (705.25->900 MHz)

Also due to the fact that one set of my UHF modulators are in another room I would like to have a stop filter that would stop any and all VHF & UHF signals below UHF 48 but allow any signals above UHF 49 to pass.. I think that this would be called a HIGH PASS filter

Due to the number of local UHF and now Digital stations in my market.. finding open UHF signals has been very tough!

How many locally modulated channels do you need? You can buy a 700 Mhz lowpass filter off-the-shelf that will pretty much pass channel 52 (698-704 Mhz). That opens up eight alternate channels for you from channels 54 to 69. Beyond that, I can't figure out what you're trying to accomplish. Winegard makes an affordable, tunable dual notch filter (UT-2700) that might not be sharp enough for you, and it is difficult to tune without specialized equipment.
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post #3 of 49 Old 04-07-2007, 06:27 AM
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Originally Posted by Rick0725 View Post

call this company and they will advise and tune filters specific to your needs and get them to you the same day. do not let the homepage scare you. they tune and manufacture the less expensive barrel notch filters.

They are a smaller company and very user friendly. They address all my filter needs.

http://www.cefilter.com

But he may be wasting a lot of money if he either doesn't need what he thinks he needs, or if narrow notch filters can't do what he needs or thinks he needs done.
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post #4 of 49 Old 04-07-2007, 07:40 AM
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You might need to check if your UHF modulators are true VSB (Vestigial Side-Band) units, too. If not, they will spill over in to the lower adjacent channel without some filters on their outputs.

Can the mods be retuned to some other block of channels? They might need to be spaced on alternate (non-adjacent) channels in some group, or groups, where you can separate them with tiering filters. Adjacent channel filtering is very expensive.

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post #5 of 49 Old 04-07-2007, 07:44 AM
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Quote:
Originally Posted by Rick0725 View Post

call this company and they will advise and tune filters specific to your needs and get them to you the same day. do not let the homepage scare you. they tune and manufacture the less expensive barrel notch filters.

http://www.cefilter.com

CE Filter is excellent, but here's another option: http://www.tinlee.com/
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post #6 of 49 Old 04-07-2007, 08:10 AM
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No residential installation can afford any available, adequate UHF NTSC adjacent channel processing. I doubt that there is a processor available in single quantities for under $400 per channel that you could rely on, but if he clears everything above channel 52 with a 700 Mhz lowpass, he can add EIGHT alternate channels. How could he possibly need more?
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post #7 of 49 Old 04-07-2007, 10:23 AM
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I can't imagine any manufacturer of filters that are not marketed to the general public being wild about getting calls from residential prospective customers who likely do not know what they want and will never provide any repeat business.
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post #8 of 49 Old 04-07-2007, 02:34 PM - Thread Starter
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Quote:
Originally Posted by AntAltMike View Post

How many locally modulated channels do you need? You can buy a 700 Mhz lowpass filter off-the-shelf that will pretty much pass channel 52 (698-704 Mhz). That opens up eight alternate channels for you from channels 54 to 69. Beyond that, I can't figure out what you're trying to accomplish. Winegard makes an affordable, tunable dual notch filter (UT-2700) that might not be sharp enough for you, and it is difficult to tune without specialized equipment.

Mike - do you have a part number for the UHF 54 and higher... this is not to be confused with the 'CABLE' notch filter as that one does not do what I need to do.

Also I have an older 'Sony DRDD-1' which is a two channel UHF modulator [Channel Master Clone] which does not do UHF higher than 36....

Currently in my market there are LP/Full/Digital stations on UHF so trying to find channels with at least a blank channel between them has been tough...

15 1.3kW K15DD America's Store - Wichita (Sedgwick) KS US
17 ->Modulated Channel for DVD-R#1
19 1000kW KWCH-DT CBS - Hutchinson (Bend) KS US

19-1: CBS (KWCH-TV)
19-2: weather radar

20 ->Modulated Channel for set top digital TV {non-HD} tuner
21 850kW KAKE-DT ABC - Wichita (Sedgwick) KS US
22 ->Modulated Channel for DirecTIVO#3
24 3470kW KSAS FOX - Wichita (Sedgwick) KS US
26 300kW KSAS-DT FOX - Wichita (Sedgwick) KS US
28 8.8kW K28JB TBN - Wichita (Sedgwick) KS US
29 1000kW KPTS-DT PBS - Hutchinson (Rend) KS US

29-1: KPTS-TV (SD/HD)
29-2: PBS Kids

31 1000kW KSCW-DT CW - Wichita (Sedgwick) KS US
33 5000kW KSCW CW - Wichita (Sedgwick) KS US
35 1000kW KMTW-DT MyTV - Hutchinson (Rend) KS US
36 3470kW KMTW MyTV - Hutchinson (Rend) KS US
38 ??kW Repeater for a Tulsa' OK LP-UHF station... they show mainly religious programs but also older '60's B&W TV shows such as 'Beverly Hillbillies'
40 50kW KFVT-LP|r.KSBI-52 ind. - Wichita (Sedgwick) KS US
45 1000kW KSNW-DT NBC - Wichita (Sedgwick) KS US
49 4.8kW KTQW-CA rlg. - Wichita (Sedgwick) KS US
51 24.7kW KSMI-LP HTVN/Bloomberg - Wichita (Sedgwick) KS US
53 ->Modulated Channel for DVD-R#2
56 ->Modulated Channel for DirecTIVO#2
60 ->Modulated Channel for Computer/Internet Weather/Security Camera

Channel 17 = Single channel UHF Modulator
Channels 20 & 22 = Sony DRDD-1
Channels 53, 56, 60 = Three channel modulator.. 'name branded "SKYWALKER"' but the same as the one sold under the name of "Holland Electronics, Inc." HMM-3


--David
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post #9 of 49 Old 04-07-2007, 03:23 PM
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It's called a 700 Mhz lowpass filter. I think Channel Plus stocks it.

I just found it here: http://www.buyextras.com/coaxialfilters.html for $26.69
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post #10 of 49 Old 04-07-2007, 04:46 PM
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Quote:
Originally Posted by Rick0725 View Post

calling them on monday morning (they were closed on Friday ).

Tinlee is very helpful, even for low quantities. The woman that answers the phone is a bit hard to understand. (oriental accent) Email works well.
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post #11 of 49 Old 04-07-2007, 06:42 PM
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Originally Posted by Rick0725 View Post

ce filter is about 6 miles from my home. I sit in the lab and watch and offer input while they tune the filter for me and I look at the charts and graphs of the lab equipment...and say...perfect I'll take it...how much?

how's that for service.

I used to have a relationship like that with Advent in Cambridge, Mass. Ah, the good old days...
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post #12 of 49 Old 04-07-2007, 08:40 PM - Thread Starter
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Quote:
Originally Posted by AntAltMike View Post

It's called a 700 Mhz lowpass filter. I think Channel Plus stocks it.

I just found it here: http://www.buyextras.com/coaxialfilters.html for $26.69

Mike -
What I am needing is a HIGH PASS filter for the UHF Channel 53 -> UP (705.25->900 MHz) AND a LOW PASS filter that blocks everything above 705.25MHz
From 3-channel Modulator ->
I want to block everything below 705.25MHz on this run of cable... just in case the cable itself is picking up any signals from local stations, air force base, ham and fm radio, before these modulated signals are mixed in to the whole house distribution.
From Antenna ->
I want to block any signals above the 705.25MHz range. {Which is what 'Buyextra' sells}

Combine the two leads ->-> whole house {Seven sets and counting}

If anybody is asking I am using 'CONE' style "IR" repeaters and JP-1 programed remotes through out my home to control all the devices.

--David
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post #13 of 49 Old 04-07-2007, 08:58 PM
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You put the 700 Mhz filter on the antenna lead. You connect that into one port of a two-way splitter/combiner. You use all modulators set to channel 54 and above. You combine those and take that combined output and feed it into the other port of the two-way splitter/combiner. You do not need to put a high pass filter on that line. If the modulated channels appear a little grainy, then you either reconfigure their combining such that the weakest one(s) get the strongest combiner path, or you put maybe a 10dB amplifier on the modulator line before mixing it with the off-air line. The liklihood of the modulator array picking up any stray signals that will be strong enough to degrade the off-air signals is near zilch.
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post #14 of 49 Old 04-08-2007, 07:12 AM - Thread Starter
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Originally Posted by Rick0725 View Post

you are going to need to move these channels up to uhf ch 54 and up with a different modulator (since your current one only goes to ch 36) . 4 input variety (one spare). spaced 2 channels apart ch 54 and up......

Yea I know I will have to spend$$ in the future as this Sony DRDD1 modulator is over ten years old....

I hope to do that when some of the remote tv sets get updated to digital tuners.

But for now and till fall... need to use what I already have due to limited funds.

--David
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post #15 of 49 Old 04-08-2007, 07:18 AM - Thread Starter
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Originally Posted by AntAltMike View Post

......The liklihood of the modulator array picking up any stray signals that will be strong enough to degrade the off-air signals is near zilch.

Well I must live near 'Zilch' then.. well really it is a FM radio tower as currently if I add the 'long run' modulator to the mix then all my off air UHF stations have "Dancing Ghosts"!

So this long run of RGQ6 is still picking up some signals that are strong enough to mess up the off air signals.

The reason there is a modulator set-up in another is room is due to limited cabinet space and limited AC Power in the main viewing/equipment room.

--David
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post #16 of 49 Old 04-08-2007, 07:41 AM
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More likely, you do not know the cause of the symptom you are experiencing.
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post #17 of 49 Old 04-08-2007, 08:21 AM
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I have searched the forum and could not find this topic.. If there is a topic such as this one please point me in the correct direction..

Took me a little time to find it, but posted this a while ago which is the same source Rick0725 recomended;

http://www.avsforum.com/avs-vb/showt...&&#post8347813

That 'Tin Lee' out of Toronto could be another choice, but I see they do have restocking fees and you have to deal with customs. CE has neither and has gone well out of their way for me. I highly recomend CE. Ask for Tracy.

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post #18 of 49 Old 04-08-2007, 12:08 PM - Thread Starter
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Originally Posted by videobruce View Post

Took me a little time to find it, but posted this a while ago which is the same source Rick0725 recomended;

http://www.avsforum.com/avs-vb/showt...&&#post8347813

That 'Tin Lee' out of Toronto could be another choice, but I see they do have restocking fees and you have to deal with customs. CE has neither and has gone well out of their way for me. I highly recomend CE. Ask for Tracy.

I have emailes both of the above suggested sources for notch filters and will wait for a reply..

--David
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post #19 of 49 Old 04-11-2007, 06:19 PM - Thread Starter
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Quote:
Originally Posted by DavidEC View Post

I have emailes both of the above suggested sources for notch filters and will wait for a reply..

Well I got the replies and one of the companies was very reasonable.. About $70 each the other ones email quote was in the $400 per channel range.. way out side of my funds...

Trouble is due to an error on my part I don't remember which was which... hit delete when I was trying to move the message to my 'email safe'..

Just spent over 4 hours with a local antenna expert.. and due to where my house is sitting I can not get a better, cleaner over the air signal due to barn and power lines....

So at this point and time I am unsure just what I am going to do...

--David
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post #20 of 49 Old 04-11-2007, 07:30 PM
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Alternate channel UHF modulators can be found on the internet for $40 per channel or less. Three of them to replace your channels 17, 20 and 22 modulators will be cheaper than any kludge filter network you can eventually develop and will work better. You probably won't even need the 700 Mhz lowpass filter. If you really are having trouble with a strong FM transmitter, you can buy an off-the-shelf FM trap that reduces either 88-108 Mhz or 93-108 Mhz by over 20dB for under $4.

Filters are not capable of both clearing channels 20 and 22 while eliminating those modulator's deleterious effects on channels 19 and 21. They are also not capable of balancing your carrier power and reducing your aural carriers. There are more problems with adjacent channel development than you realize.

I have a different class of customer than do the residential installers here. I design and install "turn-key" multichannel multi-antenna headends for a flat price of $5,000 each to provide master antenna service to apartment complexes with 100 to 800 residences.. I can't insert modulated, analog channels 20 and 22 alongside digital broadcast channels 19 and 21 at a profit selling my headends at that price.
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post #21 of 49 Old 04-11-2007, 08:33 PM - Thread Starter
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Originally Posted by AntAltMike View Post

Alternate channel UHF modulators can be found on the internet for $40 per channel or less. Three of them to replace your channels 17, 20 and 22 modulators will be cheaper than any kludge filter network you can eventually develop and will work better. You probably won't even need the 700 Mhz lowpass filter. If you really are having trouble with a strong FM transmitter, you can buy an off-the-shelf FM trap that reduces either 88-108 Mhz or 93-108 Mhz by over 20dB for under $4............

Mike - I will still need filter(s?) to clean up the upper UHF band due to what I have been told is called "Side Banding"((? ?)) because currently my TV's are picking up my local VHF-10 station on UHF 66 but in reverse black & white image (black = white) And there is so much video / non-white noise in these bands even the channels that I have assigned to 53-56-60-and moved former 43->62

I had a very nice set up till the DTV-UHF and four new LP-UHF stations when "LIVE" over the past year.. which happened to of taken the bands that I was using before....

--David
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post #22 of 49 Old 04-11-2007, 09:17 PM
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Originally Posted by DavidEC View Post

Mike - I will still need filter(s?) to clean up the upper UHF band due to what I have been told is called "Side Banding"((? ?)) because currently my TV's are picking up my local VHF-10 station on UHF 66 but in reverse black & white image (black = white) And there is so much video / non-white noise in these bands even the channels that I have assigned to 53-56-60-and moved former 43->62

Ch 10 visual carrier = 193.25 Mhz
193.25 x 4 = 773 Mhz

UHF 66 = 783.25 Mhz

My, aren't you the unlucky one? What you are seeing on channel 66 is surely the sideband of a harmonic of channel 10.

Still, you might get away filter-free by modulating the remaining three channels to UHF channels 64, 67 and 69. In fact, is there any reason you can't leave the ch 17 where it is? Then, you'd only have to find two open channels above 62.
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post #23 of 49 Old 04-12-2007, 04:46 AM
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DavidEC; Single channel 'sleave' traps from CE are around $35 each. Their better 'box' traps are $120 for a single cavity and $250 for a dual cavity (recommended for issues with adjacent channels). That company out of Toronto wanted $70 (I believe) for a 'sleave' type trap.

Normally those 'sleave' type are fine, but I have a problem with a station 3 channels away from a 'local' and need a 'tighter skirt' to the bandstop.

Here are the two versions. (Sorry for the cables blocking the larger 2 cavity trap.):
LL
LL

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post #24 of 49 Old 04-12-2007, 05:21 AM
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DavidEC; I always like a chalenge, but I would say trying to insert five channels is a bit much with all the UHF stations available. I thought I had a problem with my local overload, but yours makes my situation look like a walk in the park. Using this as a starting point since I don't know what suburb you are in;

http://tiger.census.gov/cgi-bin/mapb...el=Wichita,+KS

I get this from 2150 and see that you don't need a rotor as everything is in one direction. I also see you have a similar situation as I with 'locals' and far distant stations;

http://www.2150.com/broadcast/defaul...=Show+Stations

Questions;
Can you do without all those modulators by using baseband signals instead?
Are you using or trying to use a amp/preamp?

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post #25 of 49 Old 04-12-2007, 05:45 AM
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Quote:
Originally Posted by videobruce View Post

DavidEC; Single channel 'sleeve' traps from CE are around $35 each.Here are the two versions. (Sorry for the cables blocking the larger 2 cavity trap.):

I have to deal with several broadcast "+1" assignments: 14A/15D (next nearest, 20A), 26A/27D (five clear or weak channels on each side), 45A/46D (42D and 48D are off target), 50A/51D, 52D(distant) and 56A/57D. In these instances, gentile filters like the sleeve traps will work well to reject the nearest alternate channels. I have been able to satisfactorily separate them using Tru-Spec UHF-BPFs and MX4Us, but those products were long ago discontinued, and my inventory of them is nearly depleted.

I'm certain that the sleeve traps will be able to adequately reject the alternate channels in my situations, but I also like to attenuate the lower adjacent channels visual carrier a little, so as to reduce my distribution amplifier's load. Fortunately, all my adjacent analog channels are "-1s", so the visual carrier is about 5.7 Mhz below the "+1" upper adjacent pilot carrier, and I can tweak them to reduce the visual carriers by half a dozen dB or so without affecting the digital pilot.

I see what appear to be three holes in the case of the sleeve traps. The ones on the end look like screwdriver, "tweaking" adjustments. Are they, and what is in the opening in between them?
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post #26 of 49 Old 04-12-2007, 06:24 AM
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I see what appear to be three holes in the case of the sleeve traps. The ones on the end look like simply screwdriver "tweaking" adjustments. Are they, and what is in the opening in between them?

The outer 'sleeve' was left removed since these are used indoors and I needed to have the tuning ports exposed. I request for CE to leave the sleeve removed since it's a real 'bear' to remove it yourself. The 'slug' will accept a slotted 'tweaker' tuning tool.

CE also supplies filters for ATV Research out of Dakota City Ne. Page 51-55 of their downloadable catalog are the modulators;
http://www.atvresearch.com/

That single cavity trap is a little cheaper here, but since they are only a distributor, YOU have to tune it.
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post #27 of 49 Old 04-12-2007, 06:48 AM
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Rick0725; looks as you are in the same boat as I am and analog ch. 56 is at the top of your 'hit' list;
http://www.2150.com/broadcast/defaul...=Show+Stations

Whats' the furthest station you can receive? How do the Utica, Watertown and Kingston Ont. stations come in?

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post #28 of 49 Old 04-12-2007, 06:58 AM
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Rick075, since you're doing residential work, you probably don't have enough of a budget to mess around with something like this, but if you stack two cheap UHF antennas on one horizontal boom and point them at the desired station(s), and if the interfering signal is coming from another direction, you can gradually slide them closer and further apart, because while the desired signals will stay in phase as long as your boom is perpendicular to the transmission azimuth, the undesired signals will go in and out of phase and, at some locations, will tend to null each other out.
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post #29 of 49 Old 04-12-2007, 08:40 PM - Thread Starter
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Quote:
Originally Posted by videobruce View Post

DavidEC; I always like a chalenge, but I would say trying to insert five channels is a bit much with all the UHF stations available. I thought I had a problem with my local overload, but yours makes my situation look like a walk in the park. Using this as a starting point since I don't know what suburb you are in;

http://tiger.census.gov/cgi-bin/mapb...el=Wichita,+KS

I get this from 2150 and see that you don't need a rotor as everything is in one direction. I also see you have a similar situation as I with 'locals' and far distant stations;

http://www.2150.com/broadcast/defaul...=Show+Stations

Questions;
Can you do without all those modulators by using baseband signals instead?
Are you using or trying to use a amp/preamp?

Thanks for the links!!! They have helped alot and with the aid of a 'Google Map' may be able to prove my point to my local stations as to why I am unable to receive their signal!!

If you look at the "Google Map" and zoom into my street level you will see from the top down satellite view a 2.5 story barn.. I would have to put an a 40+ foot antenna to go above this building, and moving my current antenna to another point around my home I still can not get past the barn and/or a bunch of thick trees.

And while I don't "NEED" all the modulators when you have a wife that likes to walk from room to room and still watch the programing from the 'living/media room' and till the addition of the DIGITAL UHF stations everything had been working for seven plus years.. it has mainly been during the past three years that things have gotten tough on finding open UHF bands to "PLAY" in.

--David
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post #30 of 49 Old 04-13-2007, 12:36 AM
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It appears that you have an opportunity to place the devices in question somewhere between uhf channels ch 54 and up.

which are free for use and can be "cleaned" with an appropriate low cost filter prior to insertion.

you have not mentioned amplification. If you are amplifying, that area may need to be addressed also. overamplification can make matters worse.
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