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Message |
    
Nickel
Junior Member
Username: Nickel
Post Number: 16
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 11:13 am: | 
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I know its been covered but may be someone could help! I have a 2950 with the normal mods. An A-99 mounted at the peak of my roof line.
The only problem that I'm having is my neighbor which we share a duoplex has a tv that picks up my voice and puts one line threw his tv screen when i key up and talk. His other tv is fine.
When i look threw the other posts people just said tvi that can be anything. I know what interffering. Would a high pass filter work?????what if I use two is that better. It a new tv but its a Sanyo the cheap one might not have a filter??? I want to stay cheap. Or would a low pass be the next step. (next) my radio is grounded and I have brand new coax 99% I'm not on their phone or any other thing in their house.
Thanks Nick |
Nickel
Junior Member
Username: Nickel
Post Number: 17
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 11:23 am: |
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I forgot to add. I'm going to be moving in about two months to a place where i have neighbors really close. The high pass filter might work for my neighbor right now but when I move the low pass filter will be my only cure all. Do they really work. The only thing I need to worry about is people that have cheap tv's Does the Low-pass filter really work or is it hopeless. The new place where I'm moving has all underground wires with new phone lines and cable coax that might help?!?!?!?!?!??!?!?!?!?!?!? |
Road_warrior
Junior Member
Username: Road_warrior
Post Number: 19
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 12:43 pm: |
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How many watts are you running when you put lines through your neighbors TV???/How high is your A-99 from the ground to the bottom of Antenna???
His Tv probably has a cheap filtering system. Since your not bothering his other TV.
When I had my Imax 2000 mounted only a few feet above the peak of my house. (29 ft. to bottom of Ant)(also grounded) it caused TVI problems. I raised it up to 38ft from ground to feedpoint &
all TVI stopped./ GPK for A-99, may help also.
As for a high pass filter, 1 would be enough.
Good Luck!
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Ca346
Advanced Member
Username: Ca346
Post Number: 977
Registered: 8-2003
| | Posted on Thursday, August 26, 2004 - 12:44 pm: |
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A TVI filter will help, but in my opinion, you need to get the A99 above the TV antenna. You are radiating directly into it. |
That ELCO Guy (Unregistered Guest)
Unregistered guest
| | Posted on Thursday, August 26, 2004 - 1:54 pm: |
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In order of probable cause....
Item 1: His antenna system. What is his antenna system? Is it on cable system or an independant external TV antenna? What kind of tv transmission line are they using. External tv antennas with old leaky coax or flat line transmission line have the tendency to soak up external signals. And dare I say it, is the antenna a Rabbit Ears piece of trash?
Solution: HIGH PASS filter on the neighbors TV set. Tell them to throw away the rabbit ears and get a good antenna.
Item 2:
How close is your ANTENNA to their TV antenna. Move yours away from his by at least 1 full wave length.
Item 3:
ARE you running an amplifier, if so DONT. You may be overloading the input circuts of their TV set with a local strong signal.
Item 4:
Are you running your mic very high? Over mod will create unnecessary TVI. Back off on the power mic or better yet use the stock hand mic.
Item 5:
What channel or channels are being zapped. SOME tv channels are extremely prone to 2nd harmonics from CB radios, particularly the weaker distant ones.
Item 6: Is your neighbor running a surround system that has wire leads that are very very close multiple quarter wave lengths of the CB band. These wires may be acting as the perfect CB antenna. Solution, put torrid cores on these wires to cancel out the radio signals.
Item 7:
Now to filters, If everything else failed a good Low Pass filter may help if the problem is NOT a TV front end/input caputre problem. HOWEVER buy a good one with very steep/near vertical dropoff and with very very little frequency spurs afterwards. These GOOD ONES will not be inexpensive, you get what you pay for.
Item 8
IF you share a common house current the problem could be tha the signals are ridding piggyback into the TV set over the power plug. Install a power line filter on the TV set to block these signals out before they get to the TV set.
Item Last....
Determine that the neighbor is telling the truth. PERHAPS the problem is NOT your radio but truckers passing on the highway. See the problem for yourself and determine for yourself that the problem is as bad as your neighbor says it its.
I will close with a tip.....
When putting up any new antnna that may bring complaints by its mere presence by all means go ahead and install the antenna. BUT do not bring the coax into the building. Let the antenna just sit there. WHEN someone calls to gripe you getting on the TV ask them to come over and show them the antenna was not even hooked up, and SMILE saying well look at this not even hooked up.
It is an old ham radio trick.
Later
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Road_warrior
Junior Member
Username: Road_warrior
Post Number: 20
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 2:04 pm: |
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Do you have a A-99 or Imax 99???
Have you read Tech833's Product Reviews on the A-99?
If not,click on the Subscribers Preview section, then click on product reviews, scroll to article & discussion on A-99 Exposed. Good Article!
Let me clarify some things from my last post.
My Imax 2000 from ground to feedpoint (29ft) at 4 watts out of radio caused no TVI. The TVI came when I ran 10 watts or better. After I raised Imax 2000 to 38ft to feedpoint, I can run more wattage with no TVI problems. If I were to put a groundplane kit on my Imax 2000 it would probably help even more.
Good Luck & hope you cure your problem. JIM |
Brewdirect
Junior Member
Username: Brewdirect
Post Number: 33
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 2:11 pm: |
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I'm thinking a low pass filter will not help as much in this case...if you get along with him and can get it back later, you'd be better off to buy him a filter to use for his TV.
I put a low pass on mine to cut down on TVI with my own TV and it didn't do squat. Tried three different brands. A filter on the TV did more to solve the problem.
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Bruce
Senior Member
Username: Bruce
Post Number: 1510
Registered: 9-2003
| | Posted on Thursday, August 26, 2004 - 2:43 pm: |
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I would buy both ... copper sells a good low pass and there are places on the net that deal in TV products that sell high pass ...... you might also check best buy and other TV dealers.
i hope his tv IS on a outside antenna ........ |
Road_warrior
Junior Member
Username: Road_warrior
Post Number: 21
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 3:00 pm: |
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Nickle,
Focus on your present TVI problem. After you move it may be a whole different ballgame. Worry about that when the time comes.
Good luck! jim |
Road_warrior
Junior Member
Username: Road_warrior
Post Number: 23
Registered: 7-2004
| | Posted on Thursday, August 26, 2004 - 10:08 pm: |
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Nickel,
I found some articles on Low pass TVI filters in
the Ask the Tech section, under General Tech questions, which may help.
Let us all know how you make out & what you did to correct your problem. jim |
Cbblackbeard
Intermediate Member
Username: Cbblackbeard
Post Number: 104
Registered: 12-2003
| | Posted on Thursday, August 26, 2004 - 11:10 pm: |
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Can anyone recommend a good high pass tv filter? |
Ca346
Advanced Member
Username: Ca346
Post Number: 980
Registered: 8-2003
| | Posted on Friday, August 27, 2004 - 1:36 pm: |
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Radio Shack for the hi pass filters. Get a couple extra to keep on hand. |
Cbblackbeard
Intermediate Member
Username: Cbblackbeard
Post Number: 106
Registered: 12-2003
| | Posted on Saturday, August 28, 2004 - 1:09 pm: |
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Thanks Ca346 |
The ELCO guy (Unregistered Guest)
Unregistered guest
| | Posted on Saturday, August 28, 2004 - 4:27 pm: |
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Evening all...
I looked up a product review article in QST. If you are a member of the ARRL, it is a member only item, here is the web site....
http://www.arrl.org/members-only/prodrev/pdf/pr0208.pdf
If the reader is not a member here are the best two selections. Please pay particular attention as to model.
The best is the Valtronics ZP2500
The filter kicks in at 40 Mhz
Vertical slope after filter kicks in is almost vertical bottoming out at -80 db at 50 mhz with a perfectly flat response after that.
The cost in 02 was just under $150.00
The next best was the Benchler YA-1
The frequency the filter kicked in was not specified in the specs but the graphic representaton of filter response indicates about 30 mhz--just outside the ham 10 meter band.
Once functioning the vertical drop off was almost perfectly vertical to a -60 db at 50 mhz.
Filter response was completely flat after reaching 50 mhz--no spikes of any kind.
Price in 02 just under $100.00
The common thing to note is that the filter after reaching 50 mhz completely shut down all signal outoput. The vertical decline in the response graph shows that once these two filters kick in they shut down signal fast.
In the case of the lesser priced item the total rejection was not as deep -50 db as compared to -80 db. Either way either one would make a good choice.
There were lesser priced filters in the product review but to be quite frank, they sucked when it came to performance.
Try to get onto the web link if you can or find someone who can get on. The article is very interestiong. |
