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I installed one of the Atelicon Gas tube discharge units into the coax line to my Fm tuner and this particular model made absolutely
no improvement in reducing my static problem.I did some further
research on these units and found out that the gas tubes themselves
do nothing to reduce static.Additional electronics are added on the
DC blocked models and it is this that supposedly prevents static
from reaching the tuner.The most common method is the addition of a capacitor and a drain resistor.This method is patented by Polyphaser
and that patent is available online for viewing.However another company took this idea even further and has also been granted a patent.This model is made by Industrial Communication Engineering LTD.They use an inductor,a resistor,A gas tube.Theyre design appears
to be aimed strictly at controlling static.They claim that gas tubes
have a definite voltage rating that must be exceeded before they will
channel voltage to ground.This rating is far above the voltage of static and therefore will still transmit static voltage to the tuner.
however they will protect against a lightning strike.
The ICE model claims to be able to ground voltages as low as .01 which is well below the voltage level of static
and still pass the RF signal intact due to the use of an inductor.
I have ordered one of these units and will report here wityh my results.
Follow Ups:
by static you are refferring to 1)an actual buildup of charge on your antenna, or 2)or are refferring to ambient RF disturbances caused by a remote ESD events (lightning) showing up in your recieve. Both of these would technically be attributable to and therefore correctly be called static but how they are dealt with are completely different.If you are talking about 1) from above then you are headed down the right path looking at vaccum discharge units etc. If it is 2) then you are way off.
Please describe the exact symptoms of the static problem you are experiencing. Then someone can help you.
What do you mean by way off.
The noise I am getting is a very quick tick from time to time and other times a burst of noise.Most noticeable on the Buffalo New York
Public station I listen two.I appear to have full signal strength
and no signs of multipathing on my meters.I had this same antenna
sitting four feet off the ground with great reception.I then put it
up on a thirty foot tower with a rotator and now have this ticking and bursts of static.Apparently coax cable acts like a capacitor storing voltage and releasing iit slowly producing noise while it does so.
The main point I was trying to bring to this site is that not all these Gas discharge units are the same.Some are designed only for lightening protection.That is electrocution of people.others do this
plus improve tuner perfomance by reducing noise and static.
Yet another patented model does both of these and protects your
equipment.In a previous thread about Gas discharge units it was
basically assumed that all these do the same thing.In my research
I have found out this is not so.Gas tube units do nothing to eliminate very low voltage transients caused by wind,snow rain etc,because the voltage levels produced by static are well below the turn on voltage of gas tube units,so they will still transmit this noise.The specific model that I currently have on order is almost
aimed specifically at noise and static that are claimed to be a normal byproduct of radio and claim to eliminate this noise while also protecting people and equipment.There apparently is only one
company that makes this type which is why it is patented.
Please explain how you would deal with problem 2 if you feel I am way
off on my problem solving.
Only way off if it is 2 that is your problem right on for 1. The gas discharge units are for dispating static buildup on your equipment. They will do nothing for RF bursts showing up on your antenna caused by distant ESD events. You see there is a difference as confusing as it may seem by calling them the same thing.1) is where charge is deposited on some isolated or floating node in your system, normally your antenna. Eventually if charge keeps accumulating on the floating node it will build to a high enough voltage to ionize a current path to some charge sink such as Earth. When left to the devices of nature it seems that the most equipment damaging path is what nature chooses. That is really lame when it happens so we have workarounds. Oneway to deal with this problem is to add a more predictable discharge path that behaves as you have designed it rather than how nature dictates that it act. The gas tubes provide fair isolation for normal operation while providing a fairly low ionization voltage current path for when things start to get charged. PS one way for charge to build up quickly on your antenna is a lightning strike. These gas discharge units when designed in properly can help to address this lightning strike problem too. Note that charge buildup is correctly refferred to as static as that is exactly what it is: a static pool of charge.
2) is different. When we are talking about lightning that isn't directly striking your antenna and is sufficiently removed by distance such that it isn't causing ground bouncing etc. can still be a problem. In other words for 2) we are talking about lightning which is far away. The far away lightning is actually likely maybe like millions of amps of current or something arcing throught the atmosphere between one highly charged object and some other object which is acting as a charge sink, commonly the ground or other clouds etc. During a lightning event a very large amount of charge is accelerated, and those aware with Schroedingers equation know this acceleration of charge results in RF energy getting broadcast into the air just as if it were coming from a radio station antenna. Unfortunately the RF bursts are probably never pleasant music but more likely to be recieved and heard as white noise or pops and clicks. This is often intuitive to old guys who have been around long enough to to remember how brushed DC motors, with all their arcing sparking activity, would ruin the reception on radios and TV's in the vacinity when used. The brushed DC motors were causing the same RF bursts due to the arcing on the brushes on a small scale as the lightning does on a large scale. Obviously the lightning will produce a much more energetic burst of RF than a blender or something so it will be a problem over a much larger area. Note that this RF burst noise is often correctly reffered to as static due to the fact that it is in fact normally caused by lightning which is nothing more than ESD.
Situation 2) sounds more likely to me to be your problem given your description. The two main tools for dealing with remote atmospheric discharge RF bursts are twofold: 1) a more directional antenna 2) higher Q narrower band filters in your tuners recieve section.
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