Working Conditions
I live in Woodbridge, Virginia, a suburb of Washington, DC. The majority of my local, strong FM signals come from Washington and Fredericksburg, VA. My semi-locals are heard from Baltimore, MD, and a handful are in southern Maryland, between the Potomac River and Chesapeake Bay and southeast of Washington, DC. Most Richmond, VA and Salisbury, MD signals come in staticy year round but are stronger during the summer. A handful of signals, <70 miles to the northwest, including Winchester, VA, come in better in the car than at home in staticy mono most of the time.
My location poses some challenges when it comes to DXing groundwave and tropospheric propagation. The Appalachian Mountains, 60 miles to the west, effectively block most, if not all, regular and tropo reception from stations to the NW, W and SW. The Atlantic Ocean, 116 miles to the east, also acts as a barrier of effective tropo range to the east due to the lack of signals (or land) in the ocean.
Click to enlarge. This map shows every location I’ve received stations from via tropo since 1999.
Stations in the green zone typically come in 24/7 via groundwave. My location is just far enough inland to not enjoy the frequent summer tropo openings that bring other east coast DXers signals 400+ miles away. Instead, 90% of all tropo openings come from stations located in the yellow zone. These signals are typically too strong to let further signals override them to allow distant DX. About once or twice a year, if I’m lucky, a well-positioned tropo opening brings me stations into the blue zones in the map above.
The local Washington stations began to broadcast IBOC (HD Radio) in 2006. Being 17-25 mi away from these stations, this has negatively affected my reception of stations to the NW, especially on frequencies adjacent to my local signals. Even in the strongest tropo, it is difficult to log stations on adjacent frequencies to locals that run IBOC, however it is possible. Since 2006, my tropo openings have been mostly from the south and east, and they are generally not as strong as before IBOC was introduced. Thankfully, I can get weak tropo signals over the IBOC-affected adjacent frequencies if aimed to the SW, S and SE.
Another issue I have to deal with is that I live at the bottom of a steep hill. Indoors, local FM signals are staticy and very difficult to listen to. In a basement bathroom, I can’t pick up half of the local signals only 15-25 miles away at all. To combat the “RF hole” I live in, a roof antenna is a must for any respectable DXing. An antenna amplifier boosts signals to levels acceptable for logging weak signals.
Finally, I have to deal with some radio frequency interference (RFI) on several otherwise clear frequencies: 92.9, 105.3, 104.7 and 106.1. Most empty frequencies do NOT have any RFI in it. Thankfully, the RFI, although sounding strong when tuned, goes away and lets even the weakest tropo signal come in over it clearly.
Click on image to enlarge.
Click to enlarge. This map shows every location I’ve received stations from via E-skip since 1999.
The map above shows my effective Sporadic E-Skip range. 99% of Es is received from the 1x single hop range, typically between 500 and 1500 miles away (although I’ve had TV Es at 450 miles away and FM Es 1505 miles on different occasions). Most signals received by Es fall in the 750-1250 mile range, on average. Although rare and not experienced yet locally, signals can ‘bounce’ off two concurrent and well-placed Es clouds, theoretically maximizing the range to 2500 miles, as seen above. Most of my range in Canada is not heard due to lack of signals. The mountains that limit tropo reception here do not block Es signals at all, as these distant signals are bounced off the E-layer of the atmosphere, high above the mountains. I am far enough away from most of my locals that strong Es can overpower their frequencies, many with complete HD Radio decoded.
Even though I have a huge Es zone, the lack of signals (and well-positioned Es clouds) do prevent signals from certain areas from coming in. The map on the right map better represents my Es range. Note how most of my signals come from the midwest and from Florida, with a handful from the Canadian Maritimes.
E-skip signals typically come in with ease over frequencies adjacent to IBOC-running locals, unless I’m aimed right at the local signals. This typically only affects openings into the Canadian Maritimes to the NW.
The aforementioned RFI experienced on several frequencies is not affected by Es signals at all. Stations received by Es come in clearly without any interference.
Click on image to enlarge.
Click to enlarge. This map shows every location I’ve received stations from via meteor scatter since 1999.
The above map shows my meteor scatter range. Although the typical signal received by Ms is 300-800 miles away, I have received stations over 900 miles away via Ms. Closer signals than 300 miles are typically received by airplane scatter, but since it is impossible to tell (and the signals sound the same), I typically lump it in with Ms openings. Most of the Ms I get is to the west and south, away from the local IBOC signals.
Prior to 2006, when IBOC debuted in my area, the best Ms frequencies were 96.5, 98.5, 100.5, 100.7 and 107.5. After IBOC made all of the aforementioned signals except for 100.7 ruined by IBOC adjacent-frequency hash, I typically do not have any real good frequencies for Ms, except for 92.9, 96.7, 97.5 and 100.7. Although Ms has been heard on all of these frequencies since 2006, it is mostly unIDs and nothing like what I had prior to the introduction of IBOC.
The RFI received on several otherwise wide open empty frequencies does limit my abilities for DXing meteor scatter. Many of the aforementioned affected signals cannot be DXed for meteor scatter since it is impossible to discern the presence of a Ms ‘ping’ in waveform upon reviewing a recorded file. 92.9 FM, my best overall frequency to DX on the dial can be DXed for Ms, although the propagated signals must be loud for it to be seen in the audio file waveform.
Click on image to enlarge.
The map above shows every location I’ve received FM stations from via tropo, E-skip and meteor scatter since 1999. The map only takes note of actual city of licenses belonging to stations received, not exact transmitter locations. Also, the map does not account for multiple signals from the same city.
As you can see, the mountains have effectively created a westward ‘barrier’ between my eastern tropo states and midwest states in E-skip range. The lone dot in the Atlantic Ocean is Bermuda. Meteor Scatter has filled in the blanks between both zones but there’s still lots of stations yet to be received in Northern Virginia.
