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[W4OEQ]

I am operating digital HF from a 4th story apartment.  Using ham-stick(s) on balcony fence. Am
having great success with FT-8 gaining contacts from Australia to Alaska to South Africa, etc. But,
at the same time I am not hearing ANY signals on CW or SSB. Is this a function of the current
cycle or is it due to my minimalist antenna and the efficiency of FT-8? 73, W4OEQ

[VA2DV]

I am almost in the same situation as you. Mobile antenna (Atas-120) on my balcony. They is not much activity in the SSB part of the bands during the week except maybe for a few hours in the late afternoon. Also, the bandwidth  of an typical hamstick is quite narrow ; it may be well tuned for the digital portion of the band but completely deaf a few kilohertz away.
With a few contests coming in september, it may be a good way to test your setup, bands are then loaded wall to wall.

[KB7TT]

There is geat activity on cw and SSB.  Your antenna is probably highly compromised.  Ye, FT8 can work with a coat hanger....

[W1VT]

The best time to hear SSB/CW is during  contest weekend.  Especially one sponsored by the ARRL or CQ Magazine.

[K0RDG]

How are your Hamsticks oriented?  If you have two of them for the same band, get a MFJ 347 dipole hub and mount it horizontally..I regularly work cw and ssb on mine with that antenna inside in a ground floor apt.  Also, try using WSPR to check daily or hourly propagation patterns as well..easier to quantify than with FT8, and if you use WSJT_X for FT8 it's just a matter of switching modes.

[KD2EIP]

Ok, this is curious.  If you look at the WSPRnet map, 40 meters, 24 hours and KD2EIP then you'll see that I've been heard from Western Australia, Brazil, Uruguay, Reunion Island and most if not all of Europe.  This is with five watts on WSPR.  My antenna is a fan dipole about ten feet off of the ground.  ( The date of these results is 11/12/2021 if you're looking at this some time in the future ).

This is (I think) an almost textbook example of an NVIS antenna.  How the heck am I getting these results???  I'm also being heard on a regular basis by DP0GVN/1 in Antarctica.  Everyone keeps telling me that NVIS is for up to a couple of hundred miles at best.

[W9IQ]

Ok, this is curious.  If you look at the WSPRnet map, 40 meters, 24 hours and KD2EIP then you'll see that I've been heard from Western Australia, Brazil, Uruguay, Reunion Island and most if not all of Europe.  This is with five watts on WSPR.  My antenna is a fan dipole about ten feet off of the ground.  ( The date of these results is 11/12/2021 if you're looking at this some time in the future ).

This is (I think) an almost textbook example of an NVIS antenna.  How the heck am I getting these results???  I'm also being heard on a regular basis by DP0GVN/1 in Antarctica.  Everyone keeps telling me that NVIS is for up to a couple of hundred miles at best.

You are correctly highlighting that the general NVIS concept that no radiation goes in any other direction is completely false. Nearly all antennas have some radiation at low angles - it simply isn't as strong as other directions. You can add to the mix that even "NVIS" energy will be sufficiently dispersed (scattered) by the atmosphere so as to allow the possibility of communications beyond the so called NVIS footprint.

Many of the old school rules regarding propagation and antenna requirements are showing their limitations/errors with the low power modes of recent years.

- Glenn W9IQ

[N0GV]

FT-8 is 31 dB more "efficient" than SSB on the receiver side. It is also  around 6 dB more efficient on transmit duty cycle than SSB.

In other words an FT-8 signal being driven by 1 watt is almost 37 dB louder at a receiver than a SSB signal from the same transmitter. The equivalent is that a 1 watt FT-8 signal is comparable in S/N ratio at your receiver to a 5 kW SSB signal from the same location presuming the antennas are unchanged. Most "Good Copy" SSB is in the 20-30 dB S/N region. This means that FT-8 can accommodate an antenna system that is, politely put, a "lossy" dummy load. SSB can not.

Now lets consider a 10 Watt FT-8 signal -- it is the equivalent of a 50 kW SSB signal....

A decent analysis (not FT-8) of the effect of mode choice is in the December 2013 QST, pages 30-32. The Noise bandwidth of FT-8 is ~6.2 Hz - this determines the S/N ratio NOT the occupied bandwidth of 50 Hz. As a result it would lie between JT-65 and PSK-31 on the graphs in the article... Closer to JT-65 than PSK-31

So, your antenna is "deaf"  but you are using one of the more efficient modes of amateur communication in FT-8 - that is why you can "hear" so many more stations......


Grover