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Audiophile73
Member
Username: Audiophile73

Post Number: 81
Registered: 5-2004
Posted on Wednesday, March 22, 2006 - 4:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok some people say it's my amplifiers that cause bleed over on 11 meters, some say it's my radio doing over 100% modulation. Which one of these are true, or are both? I'm asking because I'm trying to get a base going where theres an hoa, so I want to run di poles. But if i'm gonan bleed over i need to know. I have no problem turning my radios modulation limiter down, I don't like overmodulating anyway it sounds like
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Bruce
Senior Member
Username: Bruce

Post Number: 3682
Registered: 9-2003
Posted on Wednesday, March 22, 2006 - 6:36 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok some people say it's my amplifiers that cause bleed over on 11 meters
TRUE ......
However remember most radios are not too good at rejecting strong stations so if your running power your signal will be stronger and you will be heard over more channles. As for HOA the law is they CAN ban antennas ( IF YOU ARE ILLEAGAL ) They CANNOT ban HAM antennas that already exsist in most states they must grandfather you in.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 1338
Registered: 9-2004
Posted on Wednesday, March 22, 2006 - 7:35 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you definitely need to leave the modulation limiter intact or turn it down if its a pot.

also, you must run a GOOD low pass filter after the amp.
a good one will cost more than $60.00.
dont bother buying one for less than that.

a good suggestion for you situation is to go ahead and buy a few high pass filters, some phone filters, and some ferrite beads.
if you know your neighbors at all, maybe you can be prepared with a solution, and the HOA wont ever have to know.
matt
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Chad
Advanced Member
Username: Chad

Post Number: 747
Registered: 11-2004


Posted on Thursday, March 23, 2006 - 12:23 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You can install filters to the hilt but under high power many consumer devices will experience interference. Cheap computer soundcards are a big culprit. If you live in a densely populated neighborhood proceed with great caution, somebody WILL hear you. Telephones also have problems.

When I was heavy in broadcast and manning a repair bench I did countless modifications to people’s equipment living in close vicinity to the plant. We HAD to attempt to ratify their problems. It amazes me how many people own cheap karaoke machines :-)

I run modest power here, not much at all in comparison to some. My wife's and kid's computers make excellent receivers :-) the Boy's even leaves the power amps active when the speakers are turned "off" (a real pain). OTOH My rig upstairs uses pro gear, balanced, and properly grounded. I have over 1.5KW of audio amplification cocked and ready to shoot into very efficient studio monitors. It never makes a single peep under RF. The tube amp into the listening rig is even quiet with proper grounding.

I'm staring at a new soundcard for the boy's computer in front of me to solve the problem..... and mama's computer is getting (shhhh) rebuilt for mother's day :-)

My phone system is properly grounded, no problems there. The shop stereo that I was having problems with got a cap replacement in the power amp and the use of good (RF) coax between the power amp and preamp, problem ended.

Be a good neighbor and prepared to help them. They could care less if you have a radio, they just don't want to hear it :-) If you run a clean rig, free of harmonics, 99% of all problems associated with RF overload can be solved quickly and cheaply.

Chad

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