Are Trope and E-Skip reciprocal?

[Steve_Green]

I'm sure this question has been asked before, but under tropo conditions when, say, we here in NE PA are getting all the UHF TV stations from Baltimore/D.C., is that area getting our FM and TV stations as well?

Ditto E-skip? In the same NE PA room, with just a GE SRII and then a cheesoid television hooked up to the measliest of $40 Radio Shack antennas, we heard Jazz 99 from Miami one day and saw Channel 2 Fort Lauderdale not long after (clearest picture of the lot!). On those such days, were people in Miami and Fort Lauderdale getting channel 8 from Lancaster or T-102 Pottsville on 101.9?

 

[Lawppy]

E-skip is reciprocal in nature, but openings above the FM band, thus creeping up to channel 8 are uncommon but not impossible. If people in Pottsville were hearing FM from Orlando and Daytona Beach, people in Orlando and Daytona Beach would likely hear Pottsville FM's granted there are no locals on those frequencies.

I think it's cool seeing people's e-skip reports where they hear my local stations. Meanwhile, i've just logged a decent amount of their locals.

 

[w9wi]

I'm sure this question has been asked before, but under tropo conditions when, say, we here in NE PA are getting all the UHF TV stations from Baltimore/D.C., is that area getting our FM and TV stations as well?

Yes.

However, openings (especially tropo) can be very elevation sensitive. It could be that on the Baltimore end the duct extends only from 500 feet through 1,500'. So, a DXer in Baltimore wouldn't see your local Pennsylvania stations because the duct would be 500 feet over his head.

 

[nd2023]

I've heard Long Island FM stations on tropo from NJ, and I also have heard my local NJ stations from Long Island. It really helps DXing stations that you know the formats of.

For e-skip, I heard a 100kw station from Arkansas and someone else in Arkansas heard my local 50kw CHR blowtorch 8 miles away from me at about the same time.

Tropo is usually better with stations that have more height than power. And reception of tropo is better at higher elevations.

 

[BRNout]

I don't think that tropo is always reciprocal. At least, not completely and evenly.

Quite frequently (thanks to the intrusion of off-shore moisture), FM stations from the Providence and Cape Cod markets bounce into places like Connecticut, western MA, and New Hampshire. It becomes so common during the summer that you can hear certain station from these markets almost every morning. Yet the reverse is much more unusual. Of all the summer weeks that I've spent on the upper Cape and in southern RI, only once or twice did I ever hear any FM signals from Hartford and never any from Springfield. Yet, stations like WCTK, WJFD, WCIB and WWLI pound strong signals into Hartford, Springfield and Manchester on many warm summer evenings.

And, the same is true of stations from the Portland, ME market during warm humid periods - which bounce in to NE Mass and NH during the same conditions. Yet you don't pick up a strong inland station like WGIR-FM from a place like Boothbay, ME during those same periods.

It would seem that tropo favors the coastal FM/TV signals because of where the ducting layer resides. In other words, they can duct a pretty strong signal with a solid range. Meanwhile, the inland stations hit the duct from a further distance with a much weaker signal. If they reach it at all. In other words, not completely reciprocal.

E-skip, on the other hand, does seem to be quite reciprocal. But, it's causes are different and allow for a more level playing field.

 

[vibe]

This remeinds me of growing up in the early 60's in central Conn (near Hartford). My parents purchased a B and W TV (pretty good size) and used to take it outside in the back yard where the family and friends would gather on lawn and yard chairs to watch the tube and drink some beer (soda for us young'uns). And I remember watching the Providence channels on some nights clear as a bell, despite the low elevation and distance (70 mi or so) instaead of the local channels from 10 mi away. The CBS affiliate would come in much better than channel 3 10 mi away when reception was "scrambled." We would get the NYC stations clear as a bell on the upper VHF's (7,9, 11) on some nights from about 90-100 mi away and enjoy some ball games.
We thought the TV had an unusually great tuner (which I might have worn out playing with the damn tuner) but the great reception disappeared when the seasons changed. Little did I know that the reason was summer tropo.
And on the Cape side, I've camped a number of times in Sandwich MA (Cape Cod) with my HH TV for entertainmnet (when you're alone you need something in your hand to keep you company and the TV was a lot less than $4300) The bands would open up slowly. You might get 4-5 stations at sunset but a lot later in the night (including the hartford UHF's) as the fog rolled in.
That's why many people on the eastern Conn shore can get the NYC indies (5,9,11) on many summer nights from well over 100 mi away.

 

[w9wi]

I don't think that tropo is always reciprocal. At least, not completely and evenly.

Quite frequently (thanks to the intrusion of off-shore moisture), FM stations from the Providence and Cape Cod markets bounce into places like Connecticut, western MA, and New Hampshire. It becomes so common during the summer that you can hear certain station from these markets almost every morning. Yet the reverse is much more unusual. Of all the summer weeks that I've spent on the upper Cape and in southern RI, only once or twice did I ever hear any FM signals from Hartford and never any from Springfield. Yet, stations like WCTK, WJFD, WCIB and WWLI pound strong signals into Hartford, Springfield and Manchester on many warm summer evenings.

Well, I do think it still comes back to this elevation thing. If your antenna (either receiving or transmitting) isn't in the duct, you don't get the tropo "lift". (and yes, you can be *too high*)

Note the antenna heights of the stations in these markets. The five Hartford-licensed stations are at elevations between 221 and 268 meters. The four Providence-area stations you mentioned are all at 150 +/-5 meters.

 

[BRNout]

Well, I do think it still comes back to this elevation thing. If your antenna (either receiving or transmitting) isn't in the duct, you don't get the tropo "lift". (and yes, you can be *too high*)

Note the antenna heights of the stations in these markets. The five Hartford-licensed stations are at elevations between 221 and 268 meters. The four Providence-area stations you mentioned are all at 150 +/-5 meters.

But, based on this theory, the Hartford-licensed stations should actually bounce farther during such periods. However, I have never experienced this. In fact, living in southern NH for many years, I never (ever) picked up a Hartford signal there - but got Providence, New Bedford, Cape Cod and Portland signals quite often (just as you do in CT). And, on the Cape, I only picked up WDRC once - from Falmouth back in 1981 or so. Never grabbed a Hartford signal any farther east than that.

Yet, on a humid night, Providence/New Bedford and western Cape signals can easily be heard in central CT. Given the range of transmitter sites involved on a single night - and the expansive area that Providence market stations end up with on such a night, the duct is often pretty wide. Same thing seems to happen for eastern Long Island, Jersey Shore and Delmarva stations too. Though SE New England is the most consistent I've seen.

No, I think it has more to do with the location of the enhancement, which is influenced by the infusion of low-level moisture from the ocean. That works best in coastal and very humid areas. The inland signals probably go right over the top of those conditions (which may be what you meant). Which would mean that they don't get bounced back to the ground. Either way, that would make it a non-reciprocal phenomena.

 

[vibe]

You are probably right brnout, In SW FL I have a TV hooked up to a 99 cent bow tie which is usually good for 5 stations from 30-40 mi away with reasonably good picture. But there are a lot of nites where 3-4 others that are normally fuzzy are much stronger and viewable. Sort of tropo light. I don't know how strong the duct is as I am about 2-3 mi from the Gulf.

 

[w9wi]

But, based on this theory, the Hartford-licensed stations should actually bounce farther during such periods. However, I have never experienced this. In fact, living in southern NH for many years, I never (ever) picked up a Hartford signal

Well, it *is* possible for a transmitter to be *too high*.

 

[vibe]

You may have a good point because after we moved to Rutland MA (about 1100 ft elevation if i remember) we would have a number of evenings where we would get the NYC and Scranton UHF's (a ton of them). I think their transmitting antennas are the same height as Rutland.
By contrast New Britain CT, a lot closer to NYC and Scranton by about 75 mi, the number of times we got those stations were less than a handful over a much longer period of time.
But we got the NYC UHF's a lot ( 2x or more times a week) at night from Stonington CT which is considerably further than New Britain but not as far as Rutland. But that's due to the shoreline duct.
All locations had outside antennas w/ rotors.

 

[kc0ltv]

I'm sure this question has been asked before, but under tropo conditions when, say, we here in NE PA are getting all the UHF TV stations from Baltimore/D.C., is that area getting our FM and TV stations as well?

Ditto E-skip? In the same NE PA room, with just a GE SRII and then a cheesoid television hooked up to the measliest of $40 Radio Shack antennas, we heard Jazz 99 from Miami one day and saw Channel 2 Fort Lauderdale not long after (clearest picture of the lot!). On those such days, were people in Miami and Fort Lauderdale getting channel 8 from Lancaster or T-102 Pottsville on 101.9?

Well, E-Skip usually only works up to the FM band, and often not even that far. Very rarely does it affect channel 7 or 8. So they might be hearing T-102, but channel 8 would be very unlikely.

Also, you need to consider if they have a local 101.9, or if another 101.9 in the way is blocking your 101.9.

Nevertheless, having an AIM chat with another DX'er while you're hearing their area and they're hearing your area is a blast!