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Roninboricua
Junior Member
Username: Roninboricua
Post Number: 11
Registered: 1-2006
| | Posted on Thursday, January 26, 2006 - 10:03 pm: | 
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Hi. I am about to mount my v58 this weekend. I have a ranger 2950, rgx8 coax, low pass filter (on the way), and a xforce 600, 650 rms 1200 pep.
I haven't transmitted in a while, but when i used to do it the neighbors used to complain about tvi, the could hear me on the phone, pretty much everywhere. Completly different setup with an a99.
With this new setup im trying to avoid the same thing to happen. I keep reading about "Ferrite Beads" and "SNAP ON CHOKES" for avoiding such problems. I have seen them online but I have no idea how and where to intall all of this.
Also I keep hearing that grounding your antenna causes tvi, but grounding your radio,low pass filter and amp prevent tvi.
My neighbor has one of those directional tv antennas, im already expecting trouble with that, cause i have to mount the v58 15 feet from that. but i can probably put it up higher than his, about 30 feet of the ground. not sure about the feedpoint being over his antenna.
The thing is i live on the second story of a house.How can i ground all this stuff? And can someone explain to me how to install "SNAP ON CHOKES" and "Ferrite Beads" to the coax and wherever the chockes go? Little help please?
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Bruce
Senior Member
Username: Bruce
Post Number: 3468
Registered: 9-2003
| | Posted on Thursday, January 26, 2006 - 10:22 pm: |
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they go at the base of the antenna a CHEEP way to form a choke is coil your coax about 6 times right at the antenna base. |
Road_warrior
Senior Member
Username: Road_warrior
Post Number: 1200
Registered: 7-2004
| | Posted on Friday, January 27, 2006 - 12:15 am: |
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I would mount your CB antenna as far away
from your neighbors Tv antenna as you
possibly can.
In your case living on the second floor,
the radio Rf ground wire would be to long to be
effective and would possibly radiate.
In another grounding post Tech 833 explains
what to do in this case.
Make sure you ground your antenna.
Create a choke at antenna base if you wish.
You may have to play with other ideas later
if you still have trouble...Good Luck!
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Roninboricua
Junior Member
Username: Roninboricua
Post Number: 12
Registered: 1-2006
| | Posted on Friday, January 27, 2006 - 8:52 am: |
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Im not sure im following Road Warrior, you mean wrap the coax around six times making a coil with the coax? Or get a different wire and coil it around the coax. Barney style please, im not the brightest star in the sky if you know what i mean.
And where and how do you install ferrite beads on coax, and the ground should go on the base of the antenna right? But does it have to be a copper 7' pipe. It can't be rebar, or something different? |
Hotwire
Advanced Member
Username: Hotwire
Post Number: 835
Registered: 1-2005
| | Posted on Friday, January 27, 2006 - 8:55 am: |
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If you run that big ol X Force 600 in an apartment building with you on the 2nd floor, nothing you do is gonna stop TVI, RFI, bleedover,reciever front end overload. |
Road_warrior
Senior Member
Username: Road_warrior
Post Number: 1206
Registered: 7-2004
| | Posted on Friday, January 27, 2006 - 11:38 am: |
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I would ask BRUCE about the coil as maybe he could send you a pic if he has one.
1/2 inch Ferrite cores just snap onto your
coax (Larger Coax) 1/4 inch if using mini
coax. Snap on coax under feedpoint of antenna.
And they can be used on jumpers ect.
Some people mount the groundwire on the U-clamps
that hold the mast to the antenna base. Some people ground just the bottom of the
mast pipe to ground.
Use a Copper Clad ground rod/s 1/2"- 5/8"
Use at least #6 copper wire- Larger is better
and Copper groundstrap is better yet.
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Drzuo
New member
Username: Drzuo
Post Number: 7
Registered: 1-2006
| | Posted on Sunday, January 29, 2006 - 11:36 am: |
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Remember the x-force is a class c amplifier, the worst for IMD and harmonics and offer no filtration. Add to that the fact 2sc2879's IMD figures start to go to heck pretty quick above about 70 watts pep each. The filter will help and the coil of coax also can do wonders, but if you run that amp at 600 watts it wouldn't suprise me if your imd specs were only -10db(about 60 watts of out of band harmonics. If only 100 miliwatts of that end up on the same band as his cordless phone you'd rival his phones power output. at 1/1000th of a watt on his tv channel you'd still have the power to interfere with his tv. Then as Hotwire said you have front end overload, if he has cheap equipment it'll just add to the difficulties of staying out of his stuff. |
Roninboricua
Junior Member
Username: Roninboricua
Post Number: 13
Registered: 1-2006
| | Posted on Monday, January 30, 2006 - 12:19 pm: |
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Well I put the antenna on the roof at only about 8 feet to try it out. Turned on the amp, first contact was west palm beach, great audio reports all over florida, and im in maryland. Second contact was the neighbor complaining cause i was distorting the pic and audio on his tv. He has rabbit ears on his t.v. just my luck huh.
I gave the neighbor my phone # and told him to call me if it happened again. I transmitted without the amp, on am and ssb. And received no phone calls yet. But we have a t.v. in the kitchen with rabbit ears also, and im getting in it without the amp.
And im getting on all the other t.v's, but that might be cause the v58 is two feet from the satelite, not a good idea but, its the only place i can mount the antenna right now.
I haven't gounded the antenna yet, Im going to do that today, my filter still hasn't arrived.
How can i ground the radio,coax and amp? I am in a house but i live on the 2nd floor. Im ordering ferrite beads this week also. If it comes to it I'll get the neighbor a high pass filter.
Or should I just give up now cause no matter what I do the neighbor is going to be able to hear me tru his t.v.?
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Marconi
Advanced Member
Username: Marconi
Post Number: 568
Registered: 11-2001
| | Posted on Monday, January 30, 2006 - 5:01 pm: |
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I have heard a lot of cures, but I think your final statement probably makes the most sense. Wish I could tell you different.
Now if the neighbor's wife turns on the mixer to make a cake, you will probably still be the cause of the lines on the TV, and that is likely no joke. |
Road_warrior
Senior Member
Username: Road_warrior
Post Number: 1215
Registered: 7-2004
| | Posted on Tuesday, January 31, 2006 - 12:31 am: |
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I'm tired right now,but, tomorrow i'll post
some ideas you may try.
But, with your antenna so close and running
power, overloading your neighbors and your
consumer electronics is bound to happen.
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Boxcar
Intermediate Member
Username: Boxcar
Post Number: 364
Registered: 4-2002
| | Posted on Tuesday, January 31, 2006 - 9:19 pm: |
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Bruce,
Can you actually wrap or snap them ferrite chokes right around your coax? I am in the middle of trying to ground my radio's, amp, meter and filter also. I have some of them ferrite chokes also but could never figure out where to install them. I've heard you can coil the coax around the base of the pole and/or tower a few times to try and eliminate tvi so maybe I'll try that also. I do have one question on coax, is rg213 better for tvi than mini 8(grey coax)??? |
Bruce
Senior Member
Username: Bruce
Post Number: 3482
Registered: 9-2003
| | Posted on Tuesday, January 31, 2006 - 10:59 pm: |
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YES you can buy ferite beads to snap around coax
As for TVI 213 would be better
COPPER Part# W40-00000 SNAP ON CHOKES
or
palomar-engineers.com |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1123
Registered: 9-2004
| | Posted on Tuesday, January 31, 2006 - 11:53 pm: |
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boxcar, the important part of wrapping the coax around a form is that you do it right at the base of the antenna, and that you use 18-21 feet of coax in your coil. diameter is less important, but 4" works well.(keep the wraps tight to eachother)
if you dont use the right length, it wont do its job.
matt |
Bruce
Senior Member
Username: Bruce
Post Number: 3483
Registered: 9-2003
| | Posted on Wednesday, February 01, 2006 - 6:53 am: |
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copper sells them ?????? COOL ! |
Roninboricua
Junior Member
Username: Roninboricua
Post Number: 16
Registered: 1-2006
| | Posted on Wednesday, February 01, 2006 - 3:49 pm: |
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Im still lost with the coil wrapping thing Kid_vicious. You are saying wrap the coax around the pole right under the feedline on the antenna 18-21 feet? Or make a circle 4 inches in diameter with 18-21 feet of coax and tie it up or something?
And if I do this like that where can i put the ferrite snap-ons, closest to the feedpoint or after the coil closer to the radio? |
Bruce
Senior Member
Username: Bruce
Post Number: 3489
Registered: 9-2003
| | Posted on Wednesday, February 01, 2006 - 6:43 pm: |
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both the coil of coax and the snap on ferrit beads go on the the bottom of the antenna. |
Wolverine
Advanced Member
Username: Wolverine
Post Number: 597
Registered: 2-2003
| | Posted on Thursday, February 02, 2006 - 4:12 am: |
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Ditto, what hotwire, and Drzuo said. With that size amp in a apartment building, you're asking for an eviction. Not to mention, any thing electronic (Disposable product) made these days that uses audio, or video, is subject to front end overload.
Wolverine. |
Road_warrior
Senior Member
Username: Road_warrior
Post Number: 1218
Registered: 7-2004
| | Posted on Thursday, February 02, 2006 - 4:29 pm: |
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If the TVs are being overloaded by your
transmiter: The TV circuitry is not able to
function in the presence of strong RF energy
and it is simply being overloaded.
Things you can try on TV. High pass filter,
Ac line filter, common mode chokes on feedline
and AC power leads.
If your station ground / Cb antenna feedline
are much closer to TV than is the antenna, it is
possible for the wires to be radiating and
cause problems. Not usually problem,but, possible.
If a VCR is being used with TV, unhook VCR and
use just TV, just to eliminate if it's the VCR.
Antenna being to close to ground and houses.
Increasing antenna height above ground and/or
away from problem areas can help.
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