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post #61 of 126 Old 03-29-2015, 08:13 PM
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Originally Posted by Nicholas Goss View Post
oh yipeeee.... so what do you do then, do you ground the coax antenna cable or not @Calaveras ?

Grounding the antenna or coax is only to provide a place for induced voltage from a nearby lightning strike to go and reduce the possibility of equipment damage. Lightning is DC. Indoor antennas are not normally grounded because it is assumed that the cable is very short.


I didn't know before that your antenna and AC unit were very close together. So assuming that this is an RFI problem, you need to separate the antenna and the air conditioner. RF from the switch contacts is being transmitted directly to the antenna. It shouldn't take much separation to make a big difference at UHF. No amount of grounding or line filters is going to fix a noise source to antenna problem.
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post #62 of 126 Old 03-29-2015, 09:07 PM - Thread Starter
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Originally Posted by AntAltMike View Post
Really. What do they cost? $400? Do you have a friend you can swap with?
The Kogan.com.au one was close to $400 plus shipping.
The ones in the local stores here are more like $800.

This is Australian dollars by the way.........which is more expensive than USD
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post #63 of 126 Old 03-29-2015, 09:16 PM - Thread Starter
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Quote:
Originally Posted by Calaveras View Post
Grounding the antenna or coax is only to provide a place for induced voltage from a nearby lightning strike to go and reduce the possibility of equipment damage. Lightning is DC. Indoor antennas are not normally grounded because it is assumed that the cable is very short.


I didn't know before that your antenna and AC unit were very close together. So assuming that this is an RFI problem, you need to separate the antenna and the air conditioner. RF from the switch contacts is being transmitted directly to the antenna. It shouldn't take much separation to make a big difference at UHF. No amount of grounding or line filters is going to fix a noise source to antenna problem.
Moving the antenna or hacking into the external antenna are my next investigations yes. The roadblocks for that however are restrictions in space, and the external is not mine and the house is not mine.

What is your opinion on using (see attached pic) roll of copper antenna grade RF shielding tape on the inside of the air con case to stop to emitting to the antenna??
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post #64 of 126 Old 03-29-2015, 09:52 PM
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Originally Posted by Nicholas Goss View Post
What is your opinion on using (see attached pic) roll of copper antenna grade RF shielding tape on the inside of the air con case to stop to emitting to the antenna??

Unless you can seal every gap it's not going to work. RF can come out the same place the air comes out.
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post #65 of 126 Old 03-29-2015, 09:58 PM - Thread Starter
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Originally Posted by Calaveras View Post
Unless you can seal every gap it's not going to work. RF can come out the same place the air comes out.
dang
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post #66 of 126 Old 03-30-2015, 06:59 AM
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Quote:
Originally Posted by Nicholas Goss View Post
Moving the antenna or hacking into the external antenna are my next investigations yes. The roadblocks for that however are restrictions in space, and the external is not mine and the house is not mine.

What is your opinion on using (see attached pic) roll of copper antenna grade RF shielding tape on the inside of the air con case to stop to emitting to the antenna??
Really sorry you are having this frustration. Trying to help.

OK I saw a couple of interesting comments that so far seem they need more investigation.

Not implying any of this will work, just shotgunning with the intention of troubleshooting. Identifying the path that the interference is taking and prevent inducing any new issues?

There was a comment about ground loops. Can you describe all the devices that attach to your television? Is there a disc player, receiver, subwoofer, cable/satellite, etc or just a TV? What devices are the cabling connections attaching to each other? Where are all the power cords plugged in? Where is the air conditioner plugged in? Is it the same outlet as the TV? Can you put the air conditioner on an extension cord and plug it into a different outlet? Can you put the TV on the ups and plug that into a different outlet? Can you bring power in from another room with maybe a separate circuit?

There was a comment about grounding the antenna shield. If you tap into the outdoor antenna be careful, make sure it already has a lighting arrestor block on it with a solid earth ground (maybe you want to consult local code too just in case). If not you might try grounding the shield at your tap just in case it helps. You also might want to describe the actual placement and connections of that antenna before moving ahead with it, just in case there is some issue needing to be addressed that someone here could identify for you?

As far as the copper foil is concerned, unless you have a pretty good idea of where the problem is you could just as well wrap yourself a copper foil hat for all the good it will do. You can certainly wrap connectors to seal any potential gaps but they are pretty good shields by themselves. Do you have a largish sheet of metal you can place between the air conditioner and the antenna? (nearer the air conditioner).

I have to agree at this point that given the total lack of improvement with two emi filters it is probably radiated rather than conducted. Moving the antenna might be the only solution.

Gosh I wish I could be more helpful.
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post #67 of 126 Old 03-30-2015, 08:31 AM
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Quote:
Originally Posted by Calaveras View Post
That will give you a DC ground but not an RF ground. No one tries to get an Earth ground at UHF because the lead can't be more than an inch or so long between the Earth ground and what you're trying to ground. Anything longer than a couple of inches acts like an antenna.
Why would you discourage him from making a test that might reduce the interference? The test would be inexpensive and is not likely to do any harm.

It certainly helped balm on DHC to ground his coax to reject a strong local signal that was getting into his TV after an attenuator:

ANT > first coax > variable attenuator > second coax > TV

Before grounding, even 150 dB of attenuation wasn't sufficient to block the local because it was getting into the TV after the attenuator. After he grounded the coax, only 50 dB of attenuation was needed.

balm's post:
http://www.digitalhome.ca/forum/showpost.php?p=1303652&postcount=124

Quote:
on the issue of strong analog #8, i put over 150 db attenuation just before the TV (no- amp), and the channel still comes in, with antenna facing opposite direction, i then disconnected the antenna, and put only a short coaxial (RG-6 quad shield) connected to the tv and still receive #8). so im not sure , but it seems no matter what I will do it will be received i assume along any cable connected to the tv
so i would assume an expensive tin-lee filter for #8 will not do the trick, any effective method to surpress this signal from reaching the tuner with the cable connected?
holl_ands reply:

http://www.digitalhome.ca/forum/showpost.php?p=1304006&postcount=128

Quote:
Ch8 is apparently only 7.3 miles away---AKKKK!!!!

First of all, make sure that downlead coax is securely GROUNDED as it enters the house.

You should also do a second indoor ground test, temporarily running a piece of wire between
the coax entry point on TV to convenient "ground", such as the metal chassis on an AVR
(whatever uses 3-prong AC plug)....or AC Outlet ground (screw holding plastic cover to outlet).
[BE SAFE!!!] If Ch8 signal is reduced, you can pursue a more permanent grounding approach.

You could investigate whether you are getting leakage directly into your TV by connecting
an F-Plug shorting plug to coax input.

[Poke a short piece of solid wire through the middle of an F-Plug and solder to exterior.]
[Or take short piece of coax with existing F-Plug and solder wires on other end together.]
[Or use a 75-ohm Termination Resistor Plug, inexpensive, available at Radio Shack, et. al.]
balm's reply:

http://www.digitalhome.ca/forum/showpost.php?p=1309459&postcount=137

Quote:
thank you Holl ands, and rabbit73,

i've properly grounded the coaxs, tower, and mast, with #6, and 8 ft copper rod, i have NOT YET bonded to house electrical ground

now it takes about 50 db attenuation to wipe out #8, so i would have to say grounding made the difference, thanks

with no connection to dtv, and terminator cap, #8 is nada

i also connected different short length coaxs, with open ends, and #8 is snowy to very snowy (not watchable)

aluminum on the power cord didnt appear to make a difference in image

i also ran the coax stub grounding mesh direct to the house electrical ground, with similar results

with the coax end terminated by an f-plug, or terminator cap, #8 is nada

shorting the end of the coaxs makes #8 almost clear to perfectly clear depending on method

i did notice that depending how the coax is inserted into female, moving the coax and conductor as you insert, a good image would appear, then once completely screwed on the clear image leaves, is this normal, i assume its some temporary shorting as you insert the conductor

so i assume with this proper grounding, and a good #8 filter, that should tame #8 down

however, after all this, my weak 2nd edge channels, including co-channel #13 didnt improve, in fact today was difficult to tell because i think tropo was present - and all my 2nd edge channels were not locking, this is the first time in 8 weeks, more testing to come my amp is also being used elsewhere right now

some co-channels issues should have been resolved with the switch over to digital today - but im not seeing results yet

i also tried varying attenuation on the antenna line, to reduce #8, but the least attenuation on #8, further degrades the desired weak channels (#13)

i will be re-introducing my Kitztech amp soon to see what happens, then decide on the filter

thanks for all the help
balm's post
http://www.digitalhome.ca/forum/showpost.php?p=1311702&postcount=146

Quote:
just to be sure, the fact that i had to ground the coaxial means the coax shielding is picking up signal, is this normal, could there be a problem with the cabling itself, or connectors, such as a short (contact betwen conductor and shield) or would this have the opposite effect ?
Jase88's post
http://www.digitalhome.ca/forum/showpost.php?p=1311704&postcount=147

Quote:
The coax braid is designed to capture RF. By grounding this, you protect the centre conductor from interference.
rabbit73's post
http://www.digitalhome.ca/forum/showpost.php?p=1311707&postcount=148
Quote:
Everything is normal now. Yes, the shield of the coax is picking up the CH8 signal on the outside of the shield, but it is being shunted to ground where it will not harm the CH13 signal. Meanwhile, the CH13 signal exists on the center conductor and the inside of the coax shield. No problem so far; your further tests to receive WVNY will tell us more.
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post #68 of 126 Old 03-30-2015, 09:56 AM
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Might I suggest that you contact The Wireless Institute of Australia? They may can suggest a ham radio operator in your area who might be able to assist you with your problem. Depending on what the exact source of the interference is, there are ways to connect capacitors, diodes, inductors, toroids, etc. right at the source of the interference to reduce the RF emissions.
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post #69 of 126 Old 03-30-2015, 10:03 AM
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Here's source for a Corcom 20VB1 for AUD $30.26 + s/h from Mouser's AUSTRALIA website...in Aussie Bucks.
http://au.mouser.com/ProductDetail/T...jk5bCdBQ%3d%3d

Here's source for a Corcom 20VB1 for AUD $29.93 + s/h from DigiKey AUSTRALIA website....in Aussie Bucks:
http://www.digikey.com.au/product-se...s=Corcom+20VB1

Hopefully, you can access the Manufacturer's Data Sheet, found here, showing Insertion Loss up thru 30 MHz:
http://www.farnell.com/datasheets/1482641.pdf
IF you can't see it, let me know and I'll send it to you in a PM.
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post #70 of 126 Old 03-30-2015, 10:59 AM
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Quote:
Originally Posted by rabbit73 View Post
Why would you discourage him from making a test that might reduce the interference? The test would be inexpensive and is not likely to do any harm.

It certainly helped balm on DHC to ground his coax to reject a strong local signal that was getting into his TV after an attenuator:

ANT > first coax > variable attenuator > second coax > TV

Before grounding, even 150 dB of attenuation wasn't sufficient to block the local because it was getting into the TV after the attenuator. After he grounded the coax, only 50 dB of attenuation was needed.

balm's post:

First off, I'm not on digital home.ca so I have no idea who balm is.

Second, a wire connected to ground is not an RF ground. If it worked it was just luck. You can't count on this in the general case.

The correct way to eliminate RF on the coax shield is to make a choke. You need to choose ferrite material for the correct frequency range. There are various ways to make a choke; 1) Tightly wind the coax around a ferrite rod, 2) Wind the coax on a ferrite core, and 3) Use ferrite beads placed over the coax. The latter is probably best for UHF. Amidon beads P/N FB-61-6873 are suitable for UHF and fit over RG-6. The choke should be placed very near the point of radiation or very near the point of ingress to prevent the remaining length of cable from radiating or receiving.

This is the same idea that you see used on video cables for monitors and power supplies. You never see a pigtail on these devices with instructions to connect it to Earth ground.
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post #71 of 126 Old 03-30-2015, 11:16 AM
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Nicholas Goss:

I was wondering what that fly lead was for, so I rotated the image and looked at a close up. It looks like it is a 4G filter. The filter probably has internal shielding, so the foil might not be necessary.

Anyway, when you make your test with the antenna in another room, leave the filter in-line for one test, and remove the filter and connect the antenna directly to the TV for another test.
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post #72 of 126 Old 03-30-2015, 05:27 PM
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Nicholas Goss:

Please let us know if you solve the problem.

If you can not measure it, you can not improve it.
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post #73 of 126 Old 04-03-2015, 05:24 AM - Thread Starter
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Hi guys,

@rabbit73 , @Calaveras , @holl_ands , @richart , @CherylJosie .

OK, so I bought a very long antenna cable and moved the rabbit ears to the other side of the house. Same result. Moving the antenna did nothing, not a thing.

I've got a plasma in another room, with an air-con of the exact same model type etc. It has the same issue.
BUT. The plasma is connected to an external antenna.

The 2 rooms I speak of are right next to each other.

The really mind boggling thing, is
* the the A/C in room 1, interferes with the TV in room 1.
* the the A/C in room 2, interferes with the TV in room 2.
BUT
* the A/C in room 1, DOES NOT interfere with the TV in room 2.
* the A/C in room 2, DOES NOT interfere with the TV in room 1.

TV1 = My Hisense 50K390PAD - room 1 one is my room
TV2= LG plasma - room 2 is the room next to mine, with a wall in between.

If I go taking the time to install an external antenna to this it's going to achieve nothing the same as room 2.

So the only scenario I can come up with is the antenna device/receiver inside these TV's are being affected by interference from the A/C compressor switch by radiation?

Thoughts?

Also... how to fix this without removing the A/C?
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post #74 of 126 Old 04-03-2015, 05:34 AM - Thread Starter
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Are you guys sure that putting something like that copper tape on the side of the A/C won't stop the interference going to the TV? Doesn't radiation follow line of sight just like a wireless signal? Hence the wall stopping the interference from room to room? I would have thought that putting the copper tape down the side of the A/C thats next to the TV would achieve this? I know there will still be interference getting out and about but at least I would be interrupting the line of sight to the A/C compressor?
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post #75 of 126 Old 04-03-2015, 05:47 AM - Thread Starter
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Quote:
Originally Posted by Calaveras View Post
First off, I'm not on digital home.ca so I have no idea who balm is.

Second, a wire connected to ground is not an RF ground. If it worked it was just luck. You can't count on this in the general case.

The correct way to eliminate RF on the coax shield is to make a choke. You need to choose ferrite material for the correct frequency range. There are various ways to make a choke; 1) Tightly wind the coax around a ferrite rod, 2) Wind the coax on a ferrite core, and 3) Use ferrite beads placed over the coax. The latter is probably best for UHF. Amidon beads P/N FB-61-6873 are suitable for UHF and fit over RG-6. The choke should be placed very near the point of radiation or very near the point of ingress to prevent the remaining length of cable from radiating or receiving.

This is the same idea that you see used on video cables for monitors and power supplies. You never see a pigtail on these devices with instructions to connect it to Earth ground.
Just by the way. When I made the EMI filters I also included 2 ferrite beads on each one. I made 1 for the TV and I made 1 for the A/C unit.

I pulled the A/C unit apart and placed the EMI filter way up as close to the unit's power source or what looked to me like a power source as I could.

So they look like this.... line-----cable-------ferrite bead----EMI filter-----ferrite bead-----load
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post #76 of 126 Old 04-03-2015, 05:51 AM - Thread Starter
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Originally Posted by CherylJosie View Post
Really sorry you are having this frustration. Trying to help.

OK I saw a couple of interesting comments that so far seem they need more investigation.

Not implying any of this will work, just shotgunning with the intention of troubleshooting. Identifying the path that the interference is taking and prevent inducing any new issues?

There was a comment about ground loops. Can you describe all the devices that attach to your television? Is there a disc player, receiver, subwoofer, cable/satellite, etc or just a TV? What devices are the cabling connections attaching to each other? Where are all the power cords plugged in? Where is the air conditioner plugged in? Is it the same outlet as the TV? Can you put the air conditioner on an extension cord and plug it into a different outlet? Can you put the TV on the ups and plug that into a different outlet? Can you bring power in from another room with maybe a separate circuit?
I already have the TV unit on a separate power plug, that was the very first action I took. I also made sure the only thing I had operating on the line was the TV unit and nothing else to trouble shoot the issue.

Quote:
Originally Posted by CherylJosie View Post
There was a comment about grounding the antenna shield. If you tap into the outdoor antenna be careful, make sure it already has a lighting arrestor block on it with a solid earth ground (maybe you want to consult local code too just in case). If not you might try grounding the shield at your tap just in case it helps. You also might want to describe the actual placement and connections of that antenna before moving ahead with it, just in case there is some issue needing to be addressed that someone here could identify for you?
I am using rabbit ears bro not an external (yet).

Quote:
Originally Posted by CherylJosie View Post
As far as the copper foil is concerned, unless you have a pretty good idea of where the problem is you could just as well wrap yourself a copper foil hat for all the good it will do. You can certainly wrap connectors to seal any potential gaps but they are pretty good shields by themselves. Do you have a largish sheet of metal you can place between the air conditioner and the antenna? (nearer the air conditioner).
I am not sure about this last comment of yours at this point. See my previous post from today.
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post #77 of 126 Old 04-03-2015, 05:52 AM - Thread Starter
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Originally Posted by rabbit73 View Post
I was wondering what that fly lead was for, so I rotated the image and looked at a close up. It looks like it is a 4G filter. The filter probably has internal shielding, so the foil might not be necessary.

Anyway, when you make your test with the antenna in another room, leave the filter in-line for one test, and remove the filter and connect the antenna directly to the TV for another test.
That 4G filter was only a very recent addition. While I was at the shop buying parts for the EMI filter I saw it on the shelf and it wasn't expensive so I thought why not, can't hurt.... so that's not causing it no.
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post #78 of 126 Old 04-03-2015, 05:55 AM - Thread Starter
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Quote:
Originally Posted by holl_ands View Post
Here's source for a Corcom 20VB1 for AUD $30.26 + s/h from Mouser's AUSTRALIA website...in Aussie Bucks.
http://au.mouser.com/ProductDetail/T...jk5bCdBQ%3d%3d

Here's source for a Corcom 20VB1 for AUD $29.93 + s/h from DigiKey AUSTRALIA website....in Aussie Bucks:
http://www.digikey.com.au/product-se...s=Corcom+20VB1

Hopefully, you can access the Manufacturer's Data Sheet, found here, showing Insertion Loss up thru 30 MHz:
http://www.farnell.com/datasheets/1482641.pdf
IF you can't see it, let me know and I'll send it to you in a PM.
Thanks for this. At this point I might have to buy one of these for the A/C unit. Starting to look like it might be the only solution. Not that I already have one inside the unit it shouldn't be hard to switch it over with one of these.
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post #79 of 126 Old 04-03-2015, 07:35 AM
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Quote:
Originally Posted by Nicholas Goss View Post
Hi guys,

@rabbit73 , @Calaveras , @holl_ands , @richart , @CherylJosie .

OK, so I bought a very long antenna cable and moved the rabbit ears to the other side of the house. Same result. Moving the antenna did nothing, not a thing.

I've got a plasma in another room, with an air-con of the exact same model type etc. It has the same issue.
BUT. The plasma is connected to an external antenna.

The 2 rooms I speak of are right next to each other.

The really mind boggling thing, is
* the the A/C in room 1, interferes with the TV in room 1.
* the the A/C in room 2, interferes with the TV in room 2.
BUT
* the A/C in room 1, DOES NOT interfere with the TV in room 2.
* the A/C in room 2, DOES NOT interfere with the TV in room 1.

TV1 = My Hisense 50K390PAD - room 1 one is my room
TV2= LG plasma - room 2 is the room next to mine, with a wall in between.

If I go taking the time to install an external antenna to this it's going to achieve nothing the same as room 2.

So the only scenario I can come up with is the antenna device/receiver inside these TV's are being affected by interference from the A/C compressor switch by radiation?

Thoughts?

Also... how to fix this without removing the A/C?

Unfortunately this highlights how difficult it can be to troubleshoot these problems over the internet. We could continue to speculate here but what you really need at this point is someone very experienced in troubleshooting interference problems to go to your place, probably with a spectrum analyzer and start from scratch.

Sometimes important details get left out. For example, in this post I just found out you have two different ACs in two different rooms causing the same problem to two different TVs. I thought it was one AC and one TV. How was I not aware of this? There may be other important details that we need to know.

Sometimes the symptoms don't make any sense. The interference doesn't extend into another room yet moving the antenna far away doesn't fix it. That's inconsistent with the idea of RFI. When I've run into these sorts of inconsistencies in the past I've found the best course of action is to ignore everything I've been told and start over from scratch.

Last edited by Calaveras; 04-03-2015 at 07:40 AM.
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post #80 of 126 Old 04-03-2015, 07:47 AM - Thread Starter
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Originally Posted by Calaveras View Post
Sometimes important details get left out. For example, in this post I just found out you have two different ACs in two different rooms causing the same problem to two different TVs. I thought it was one AC and one TV. How was I not aware of this? There may be other important details that we need to know.
I'm not being rude but if you go back through the comments I have mentioned the 2 TV's and 2 A/C's thing more than once.

I am not going to be able to have someone come in for a month or so...so... in the meantime....I can only hope the advice continues to flow.

Last edited by Nicholas Goss; 04-03-2015 at 07:50 AM.
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post #81 of 126 Old 04-03-2015, 07:49 AM - Thread Starter
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Sometimes the symptoms don't make any sense. The interference doesn't extend into another room yet moving the antenna far away doesn't fix it. That's inconsistent with the idea of RFI. When I've run into these sorts of inconsistencies in the past I've found the best course of action is to ignore everything I've been told and start over from scratch.
Line of sight.

The wall between room 1 and 2 is a complete wall with a built in cupboard.

Thw room the antenna went to is the lounge-room that connects to my room via a door. So I moved the antenna in terms of distance, but not line of sight.

So there is a difference here.
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post #82 of 126 Old 04-03-2015, 08:08 AM
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Re: Post 74.

I'm far from an expert,..But knowing how effective copper foil tape can be inside an
electric guitar control cavity at blocking radiation from fluorescent lamps & such, and
how much effort you've already expended, it's worth a try.
I'd just use cheap & readily available alum. foil, as a test. The better you can surround
the motor & switches the better the chance of success.

Good luck.
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post #83 of 126 Old 04-03-2015, 08:30 AM
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Two rooms... two antennas (different)... two TV's (different)... two different electrical circuits... two Air Conditioners (same make/model) that each cause the same "problem".
Hm-m-m-m... Makes one consider a potential common denominator.
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post #84 of 126 Old 04-03-2015, 08:43 AM
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Quote:
Originally Posted by Nicholas Goss View Post
I'm not being rude but if you go back through the comments I have mentioned the 2 TV's and 2 A/C's thing more than once.

I am not going to be able to have someone come in for a month or so...so... in the meantime....I can only hope the advice continues to flow.

I understand but there's the problem. You're intimately familiar with your setup. We know nothing. A piece of information in one comment, another piece in another comment and so forth. It's very hard to put that together into one coherent picture. That's why it's so hard to troubleshoot these problems in a forum format.
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post #85 of 126 Old 04-03-2015, 08:51 AM
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Did you ever run the test of operating the TV set(s) solely off the UPS?

Tech support for Antennas Direct
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post #86 of 126 Old 04-03-2015, 12:01 PM
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Quote:
Originally Posted by Nicholas Goss View Post
Line of sight.

The wall between room 1 and 2 is a complete wall with a built in cupboard.

Thw room the antenna went to is the lounge-room that connects to my room via a door. So I moved the antenna in terms of distance, but not line of sight.

So there is a difference here.
Didn't see you trying to put a ferrite core on the coax cable itself installed right next to the TV. Amaz*n sells a ferrite core for 1/2 inch diameter cables. Multiple cores may be required because one may not be enough. RF interfering signals can be picked up by the coax shield and enter the TV, grounding helps, but adding a ferrite core may make more off a difference.

See:http://www.arrl.org/cable-television-interference
Section: The Common Mode Filter
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Last edited by retiredengineer; 04-03-2015 at 03:04 PM. Reason: added reference
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post #87 of 126 Old 04-03-2015, 07:47 PM - Thread Starter
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Quote:
Originally Posted by DDK65JAG View Post
Re: Post 74.

I'm far from an expert,..But knowing how effective copper foil tape can be inside an
electric guitar control cavity at blocking radiation from fluorescent lamps & such, and
how much effort you've already expended, it's worth a try.
I'd just use cheap & readily available alum. foil, as a test. The better you can surround
the motor & switches the better the chance of success.

Good luck.
I am not sure foil is a good RF shield. Copper is but I am not sure about foil. I think I am just going to hit the A/C with the copper tape today. Nothing bad will happen...can't hurt...if it doesn't work then I can always just pull the tape back off.
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post #88 of 126 Old 04-03-2015, 07:48 PM - Thread Starter
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Quote:
Originally Posted by Calaveras View Post
I understand but there's the problem. You're intimately familiar with your setup. We know nothing. A piece of information in one comment, another piece in another comment and so forth. It's very hard to put that together into one coherent picture. That's why it's so hard to troubleshoot these problems in a forum format.
Thanks for you help anyway. I will let you know when it's finally solved one way or the other.
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post #89 of 126 Old 04-03-2015, 07:50 PM - Thread Starter
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Quote:
Originally Posted by Ratman View Post
Two rooms... two antennas (different)... two TV's (different)... two different electrical circuits... two Air Conditioners (same make/model) that each cause the same "problem".
Hm-m-m-m... Makes one consider a potential common denominator.
Well we already know that the A/C is the issue. Every A/C is going to cause this same problem. It's am issue with compressor switches causing a viltage spike big enough to cause an RF interference.

The issue is not not "what" but "how to fix".
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post #90 of 126 Old 04-04-2015, 06:02 AM
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Quote:
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Every A/C is going to cause this same problem.
Has that been proven or just your assumption? IMHO, is that were true, everyone that uses a window unit A/C and uses an antenna would have the same issues as you.
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