New Part 15 Florida

[Ermi Roos]

... It would not surprise me if US agents are directed not to cite for field strengths lower than 1000 uV/m at 3 m. Such an allowance would account for imperfect measurements caused by reflections and other terrain effects.

Field strengths produced by a "Part 15 FM" transmit system based on measurements made considerably further than 3 m away from the transmit antenna cannot be extrapolated to the true value of the peak field existing 3 m away from such a transmit system -- accurate as those distant measurements may be for the fields existing at those locations beyond 3 m.

In such cases and depending on path geometries, reflections/obstructions/terrain effects for those distances can produce a REDUCTION in received fields, rather than their improvement over the theoretical fields for free-space, unobstructed paths.

A single, in-phase reflection arriving at the receive antenna from a surface having a reflection coefficient of 100% improves the free-space field there by about 6 dB.

Such a reflection received 180 degrees out of phase from the free-space field (due to path geometries) completely cancels that free space field.

No NEC graphs?

 

[amlover]

Nice website! I like it.

 

[pascoradio]

Since you are an EMC engineer, John, you would be very familiar with standardized tests, test specs, and test ranges.

Thanks Ermi. What is interesting is that if you place the Part 15 documentation along side the Industry Canada, (formally DOC) it is nearly word for word the same. Excluding French of course.

 

[Ermi Roos]

Despite the similarities, there are still significant differences between the FCC and Industry Canada rules. The considerably higher FM field strength allowed in Canada has already been noted. For AM, Canada allows 250 uV/m at 30 meters if the 100 mW and 3 meter limits are not met. Section 15.209 allows only about 14 uV/m at 30 m when the 15.219 conditions do not apply, which is well below the atmospheric background noise in the AM band. At least the Canadan limit is above the noise floor!

 

[Ermi Roos]

Pasco County--Right! I assume you had a little difficulty (as I did) logging on after the Upgrade.

 

[Ermi Roos]

I mentioned the lowest-power FM station in this thread that I know to have been issued an NOUO. To put things into perspective, I want to say that I just saw an NOUO for the highest-power FM station that I know to have been cited. The field strength reading is 314,464 uV/m at 3,548 meters. Conversion of field strength into radiated power is not exact unless the gain of the antenna is known, and the terrain is flat and highly conductive, but a consevative guess is that this station has possibly more than 10 kW of radiated power. The NOUO was issued to Wellington Espinal of Paterson, NJ on September 4, 2013. The transmitter and other station equipment must be very valuable, and the owner probably would want to protect his property. I would guess that the FCC agent brought backup before knocking on the door.

 

[RadioMan203]

The NOUO was issued to Wellington Espinal of Paterson, NJ on September 4, 2013.

Of course New Jersey is one of the states which pirate radio transmissions are also accompanied by local (i.e., state) legal action / law enforcement.

 

[Ermi Roos]

Part 15 in Florida

The governor of New York signed such a law in 2011. These days, the really powerful unlicensed (kilowatt plus) FM stations seem to concentrated in NYC and the metropolitan area. A few years ago, the highest power pirates (as indicated by field strength data in NOUOs) were in the Miami area. Florida also has an anti-pirate law.

 

[Ermi Roos]

I wondered if FCC employees, such as field agents, district directors (like Mr. Barlow, mentioned in this thread), and the like, would be considered to be "essential" during the government shutdown. Perhaps not! The FCC website says that the the essential employees in the Enforcement Bureau are a senior manger (maybe the Bureau Chief) and two staff members. The senior manager may designate other essential employees if needed. Well, Barlow has been Tampa District Director for 39 years, and very likely he is old enough to retire if he wishes. It will be interesting to see if he returns when the shutdown is over.

 

[pascoradio]

I wondered if FCC employees, such as field agents, district directors (like Mr. Barlow, mentioned in this thread), and the like, would be considered to be "essential" during the government shutdown. Perhaps not! The FCC website says that the the essential employees in the Enforcement Bureau are a senior manger (maybe the Bureau Chief) and two staff members. The senior manager may designate other essential employees if needed. Well, Barlow has been Tampa District Director for 39 years, and very likely he is old enough to retire if he wishes. It will be interesting to see if he returns when the shutdown is over.

He also drive more than 50 miles each way to get to work.