This is a good tutorial for grounding anything in your Part 15 AM station. Though amateur radio related, it provides a good understanding for the beginner.
http://kc.flex-radio.com/KnowledgebaseArticle50426.aspx
This may be something to look at too for part 15 AM especially if they ever change the rules. If we start getting RF into our own equipment due to lack of a good ground or lack of RF ground. Now this is another reason we need to abolish the ground lead rules for part 15 AM because lack of good RF ground could cause interference and voltage build up to occur especially if a part 15 15 AM station was to operate inside an apartment complex. It is really a area the FCC needs to take a second look at. First there is the safety issues and second there is the RF build up caused by the lack of a counter poise. Again thanks for bringing this up.
Since I am planning to build my first outdoor AM antenna with radials I am worried about the transmitter being close to the ground where kneeling down to tune it every once in awhile will be uncomfortable and present a risk of electrocution if the ground is moist.
It seems that mounting the transmitter up at 36" above the ground (1-yardstick) would make it a lot easier, more comfortable, and safer. Then of course there would be a 36-inch "convenience" ground lead down to the rod/radials with the 3-meter pipe up above.
Am I to believe that there are some people so bound-in-knots about "The Little Rules" that 36-inches of ground lead would cause insomnia and loss of appetite?
Doubt any such person would reveal so deep a pettiness.
Mr Blare posted in Reply 3 of this thread: Since I am planning to build my first outdoor AM antenna with radials I am worried about the transmitter being close to the ground where kneeling down to tune it every once in awhile will be uncomfortable and present a risk of electrocution if the ground is moist.
Just to note that such tuning efforts are best made by trial and error with the transmitter turned off -- based on system performance after the adjuster has moved well away from that antenna system and the system is re-activated.
So there will be little risk of "electrocution" as long as such tuning does not take place with hazardous conditions such as during local storms having lightning activity.
Those who comfortably cannot kneel/crouch down for a minute or so to reach the settings of a loading coil mounted several inches above the surface of the earth have issues not related to electronics.
Then of course there would be a 36-inch "convenience" ground lead down to the rod/radials with the 3-meter pipe up above.
Please supply your reference to anything in Part 15 that permits the use of a "convenience" ground lead for unlicensed AM systems that legally supports your belief, when such a conductor results in a radiating length that exceeds §15.219(b).
Hi Rich. We expected to hear from you. Have you had your milk? How does your social worker think things are going?
Mr Blare's evasion, diversion and ridicule in Reply 5 of this thread is far easier to produce than valid justification for Mr Blare's posted comments in Reply 3 of this thread.
However such responses do not serve him (or the rest of us) well.
Didn't the certification process of the am1000 and another transmitter/antenna combination have these transmitters sat on a 1 metre high table, with the ground lead connected to a radial system on the ground ?
Paul.
Inmate Fry says: "However such responses do not serve him (or the rest of us) well."
Who do you mean by "the rest of us"? You are not a part 15 practitioner.
Look again and see that I posted my concept as a "thought." As such, do you believe it's a thought crime?
Were you to build a part 15 system you could take full responsibility for antenna/ground lengths and such.
When I build a system the legality of how I do it is no concern of yours.
As well I could apply for a waiver from the FCC for small bits of extra wire.
BOARDMAKER spotted the excellent comparison to be made between my proposed design and extant practice.
Your judgement is premature and your bringdown overly harsh.
Mr Blare posted in Reply 8 above: BOARDMAKER spotted the excellent comparison to be made between my proposed design and extant practice.
Just to note that neither a "proposed design" nor an "extant practice" necessarily do not, and probably seldom replicate the conditions used in the Part 15 certification of a given, unlicensed AM transmitter system.
In any case, such an FCC certification under Part 15 AM is not transferable/applicable to AM transmit systems that have not formally been certified under Part 15, such as those favored and promoted here by Mr Blare.
Except in case of waiver.
Mr Blare posted in Reply 10: Except in case of waiver.
Please keep us apprised of your attempts, and results.
Your approach seems somewhat retentive, but we'll be running the idea by a professional FCC qualified consultant probably around 2017.
stop bickering and stay on topic?
Neil
Yes and no. Yes there is a 0.8 meter ground wire attached. And no, it's not a radial system but a conductive turntable.
By studying the white paper on grounding featured in John WDCX's opening post (#1) and relating it to the hypothetical Part 15 system entertained in my (Carl's) Post # 3, we find two potential solutions to the question of raising the RF ground by 36-inches above the earth for the purpose of locating the AM transmitter at a convenient height for maintenance.
Those ostensible methods are "Alternative 1 - The Counterpoise", and "Alternative 2 - RF Supressor Ground System."
These solutions are presented in the paper to address the problems encountered by HAM radio operators in upper floors of buildings, sharing many of the same grounding problems encountered by Part 15 stations.
Another solution to my own proposal of a "comfortably located transmitter", devised in my own mind, is to place the transmitter at ground level with a 36-inch deep access pit located at the antenna, covered with a removable manhole cover for safety, drained to avoid rain water collection.
What is being "solved" in all these alternatives is the matter of exceeding the 3-meter limit of 15.219 by 36-inches as first described in Post # 3. For purposes of understanding the minutia of it, we would wonder by how many fractions of a foot such excessive antenna length would add to the transmitter's range, if any.