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Johhn
Intermediate Member
Username: Johhn

Post Number: 128
Registered: 8-2007
Posted on Friday, May 02, 2008 - 8:27 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I did the analog to digital T.V. switch,
Only changing tv's now my radio hits the signal
of digital and the screen will go blank.
I now installed the t.v.intereference filter from R.S. but nogood .I put a Low pass filter
#1089 .I turned down wattages to 4,some bettter. Digital will still go blank.help Johhn.
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Tech237
Moderator
Username: Tech237

Post Number: 991
Registered: 4-2004
Posted on Friday, May 02, 2008 - 8:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Check all connections especially any cables you just added. Also all your grounds.

If you are interfering with a Digital TV signal you have a leak somewhere.

What brand of tv or converter are you using??
Simon
Tech237
N7AUS

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Bruce
Senior Member
Username: Bruce

Post Number: 4695
Registered: 9-2003


Posted on Friday, May 02, 2008 - 10:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Whan band are you on ?
On 6 since 66
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4223
Registered: 7-2004


Posted on Friday, May 02, 2008 - 7:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i have 5 flat panel digital hd tv's with digital cable boxes along with my computer monitor. radios range from ft101e to modern HF xcvr and everything in between, including tweaked 706mk2g, & all kinds of CB's & exports. 1 tv is less then 5' from all my radios. i get NO interference from ANY of the tv's and GIVE NO TVI to ANY of the sets-EVEN with dvd players or PS3 running. rg6 quad tv cable & doubled shielded quad jumpers(!), digital approved splitters on ALL TV cable runs, PLUS 9086/lmr240 & 400 on ALL radios & jumpers, with properly grounded EVERYTHING. NO TROUBLES ANYWHERE on any band including 6m, 10m, 11m, & 12m. some of the radios are well modded & probably TVI machines-but not in my shack. my neighbor is amazed at no problems here, yet i STILL can wipe out his coiled up, 20 year old 250' piece of rat shack trash cable coax & rat shack amp to get cable signal 50' away through the mess....he decided to live with some tvi rather then spend $50 & fix it right.....
cable-cable-cable....not neccessarily a cure-all, but it should help when quality equipment is used.
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Johhn
Intermediate Member
Username: Johhn

Post Number: 129
Registered: 8-2007
Posted on Friday, May 02, 2008 - 10:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Maby it is you went with a flat panel,
My RCI 2950 dx is on 11-meter band.
Mine did not have intfer.untell we
switched T.V.s,The new one is a Sansui,
Tube 27".We use a antenna on the roof,
for locial channels.It did not do this untell
We switched. I have 5-grounds.
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Johhn
Intermediate Member
Username: Johhn

Post Number: 130
Registered: 8-2007
Posted on Friday, May 02, 2008 - 10:31 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

We use rg-6 cable, It will not go through
The sat.broadcast. the same stuff is on the old setup The roof ant. and it is 50 ft away.
Pat :did you you say yours is hd cable.
Mine is recieving the digital threw the antenna on the roof.. o.k. my swrs are 1.2 highest.
On c.b.band..
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Johhn
Intermediate Member
Username: Johhn

Post Number: 131
Registered: 8-2007
Posted on Friday, May 02, 2008 - 10:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Will you post today ????
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Johhn
Intermediate Member
Username: Johhn

Post Number: 132
Registered: 8-2007
Posted on Friday, May 02, 2008 - 10:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

O.k.
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Tech237
Moderator
Username: Tech237

Post Number: 992
Registered: 4-2004
Posted on Saturday, May 03, 2008 - 12:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Correct me if I am reading it wrong, but you bought a digital tv and replaced you old analog one??

If you still using all the same cable as before then the obvious potential problem is the Sansui cannot handle out of band (TV band that is ) signals. What happens if you tune the tv to an analog signal, do you still have problems??
Simon
Tech237
N7AUS

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Johhn
Intermediate Member
Username: Johhn

Post Number: 133
Registered: 8-2007
Posted on Saturday, May 03, 2008 - 9:01 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yes if I tune the T.V. to Analog it dose the same thing in respect.
Digital Blank screen,Analog Shimming melted
Horizental bars accross the center of
the picture..
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Tech237
Moderator
Username: Tech237

Post Number: 993
Registered: 4-2004
Posted on Saturday, May 03, 2008 - 10:33 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

That is really starting to sound like the tv cannot reject out of band signals, probably due to poor (read non-existant) shielding.

If that is the case, about the best thing you can do is talk to the manufacturers and get there suggestions, but I seriously suspect you may be just out of luck with that tv. Maybe take it back and exchange it for a different may be an answer.
Simon
Tech237
N7AUS

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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 4224
Registered: 7-2004


Posted on Saturday, May 03, 2008 - 12:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

johhn, you are receiving your hd signal through a rooftop antenna, correct? how far is the cb antenna away from the tv antenna? get them as far apart as possible. are feedpoints near the same plane? get one much higher then the other. is there ANYTHING else in line between the antenna & the tv? if there is, try removing it so that is all you have-1 piece of coax, & see what happens then.

yes, i have cable tv & use an interactive digital set top box model 4250hd by scientific atlanta. through the house, i use rg6 quad cable, it is foil/braid/foil/braid, and i see no difference in using crimp on vs compression fittings. this cable starts right where it enters my house, then goes to a 5 way commercial-type approved for digital service splitter. at that point, runs are 2 at <20', 50', 65', and then another splitter at about 40' going another 15-30'. in THAT mess is the 5 hd flat panels along with 2 crt tv's. the jumper cables to all accessories are 'armored' rg6 quad. the hdmi cables from the digital boxes to the tv's(3 are sony, 2 are by insignia) are extremely heavy & 'armored' in appearance, & also advertised as 'extra protection from interference from external transmitters, etc....'. is this overkill? maybe, maybe not-i get no interference to my sets. since i rewired my whole house with rg6 quad, the ONLY crt tv i have that experienced trouble in the past, a 'superscan' with built in dvd & vcr & 'dual front firing speakers' is now trouble free. radio transmitted audio used to come through the internal speakers at a consistant volume-no matter the output wattage-but at different levels on different channels. i ASSUMED it was just overload for which there would be no cure, but the change to rg6 quad eliminated that problem too. another neighbor across the street, a good 150'+ from my cb antenna always experienced overload to the speaker system of his rca tv with surround sound-even with the tv OFF. it got louder with the tv on. he got little if any interference on the other tv's in his house. i gave him 30' of rg6 quad, and the interference to the speakers when the tv was OFF went away! when he removed the surround sound & just used the tv, there was NO interference. as far as i know, he never hooked up the surround sound again.
as simon states(was gonna say simon-sez, but.....), non-existant shielding is quite possibly a major cause, and interference is not just getting in through the coax/antenna, but via overload from rf. i'm using 2 'less-then-name-brand' hd flat panels & 1 'less-then-name-brand' crt tv (which i would guess to be poorly shielded/filtered)& DO NOT interfere even at 150+ watts PEP, including some heavily tweaked, peaked & clipped radios. my neighbor with the rat-shack-rats-nest of 250' of wire only going 50' would have his digital box freeze up to the point of needing to reboot at the very instant i keyed an 80 watt PEP SSB 6 meter signal, or my 40 watt S9 on CB. i had to back 6 meters down to about 12 watts & the S9 to about 20 watts before i wouldn't freeze the box.
if at 4 watts you STILL 'blank out' the digital, yes, i'd see if the dealer would exchange the tv. BUT, i seriously doubt that if everything is properly grounded-CB, antenna, tv, tv antenna, house electric, etc-AND you use rg6 quad cable to the TV AND a HIGH QUALITY(PREFERABLY DOUBLE SHIELDED SUCH AS 9913, 9086, LMR, ETC)COAX to the cb, 4 watts would interfere with ANY tv.
by the way, since going rg6 quad, i see little if any 'squiggly' lines to ANY of MY tv's when i key 200/800 PEP in my driveway. . 3.5kw PEP and all bets are off .
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Johhn
Intermediate Member
Username: Johhn

Post Number: 134
Registered: 8-2007
Posted on Wednesday, May 07, 2008 - 8:35 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Patz;The antenna booster was changed.
Now I changed the piece of patch at the antenna amp.On top from, Rg-58 too Rg-6,
Still same thing.The R.S.Booster will have
Too be changed to a Channel Master.
The channelmaster has a out of band
Rejuction filter, R.S. says nothing about...
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Johhn
Intermediate Member
Username: Johhn

Post Number: 136
Registered: 8-2007
Posted on Wednesday, May 07, 2008 - 8:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The C.B.antenna is 10'above the T.v.antenna.
The T,V.antenna is 40'or so from each other.
So eather it is the booster i had to change for digital,or the Digital won't C.B...
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Johhn
Intermediate Member
Username: Johhn

Post Number: 137
Registered: 8-2007
Posted on Wednesday, May 07, 2008 - 8:38 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If anyone knows of a filter for digital,
speak now....Johhn.
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Johhn
Intermediate Member
Username: Johhn

Post Number: 139
Registered: 8-2007
Posted on Monday, May 19, 2008 - 8:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Up date; Will all is good now,
The R.S. T.V.I.Filter I was using,
Behind the T.V.set,was in the wrong spot!
On someone's website They reported that you,
Must try putting it on up closest to the antenna,
as posable. between the antenna adapter,
And the coax,befour it gose into the booster.
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Johhn
Intermediate Member
Username: Johhn

Post Number: 140
Registered: 8-2007
Posted on Monday, May 19, 2008 - 8:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yes that is rigth ; Just like I said;
On the roof up next too the tv antenna,
You see the adapter first.
It is the 300ohm to 75 ohm adapter.
Turn the filter around backwards.
The filter has a short piece of rg58 on it.
I cut the conector off and put a ferite core on it,also. No more interference in my house..
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Johhn
Intermediate Member
Username: Johhn

Post Number: 141
Registered: 8-2007
Posted on Monday, May 19, 2008 - 9:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

O.K.so Radio Shack's Antenna Booster for Digital,
Has no filter for Radio interference.
The band for tv is 300.00mhz to 550.00mhz.
the channel guard is 88.ooomhz
Or the tvi filter has 52.000 to 550.00mhz
On it. We are below 52.000 mhz .
Something so Cheep,Can fix this.johhn 361 38-lsb
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Johhn
Intermediate Member
Username: Johhn

Post Number: 143
Registered: 8-2007
Posted on Tuesday, May 20, 2008 - 10:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This is the $5.00 Radio Shach T.V-vcr Filter
That I used for this fix..
Rember the filter, is it's strongest
Clostest too the antenna I was bleading over..

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