Physics Lab
18 operator-grounded test paths from 49,233 QSOs and 5.7M contest signatures. Each path is validated against ionospheric physics.
Must Open
10
Paths actually worked
Must Close
6
Physics says no
Band Order
2
Day vs night ordering
10m — The Acid Test Band
10m East Coast — Daytime Open
hard"F2 skip, solar-illuminated path, high SFI, band wide open"
97 QSOs DN46→FM19 on 10m, peak at 19z, peak month Dec
10m East Coast — Night Closure
hard"F2 layer collapsed, 28 MHz cannot refract, band dead. Not an operating habit — physics."
0 QSOs at 03z on 10m in KI7MT log. Contest data: 10m NA→EU at 02-04z = 45 QSOs vs 472K at 14-16z (10,000:1 ratio).
10m East Coast — Summer Dead Season
hard"Summer F2 critical frequency too low for 28 MHz skip. Physics, not habits."
0 QSOs on 10m in Jun/Jul in KI7MT log. Contest data: 10m NA→EU Jul = 42 QSOs vs Oct = 299,500 (7,000:1 ratio).
10m EU Path — Daytime Open
hard"Transatlantic F2, solar-illuminated, high SFI, classic DX path"
170 EU QSOs on 10m, hours 14-19z, peak Oct-Dec
10m EU Path — Night Closure (THE ACID TEST)
ACID TESThard"Both ends in darkness, F2 collapsed, 28 MHz impossible. Ham Radio 101."
0 EU QSOs on 10m after 19z in KI7MT log. Contest: NA→EU 10m at 02-04z = 45 QSOs total across ALL contests. V22-gamma predicts +3.7σ here.
10m Japan — Afternoon Open
hard"Trans-Pacific F2 long path, high SFI, JA morning/MT afternoon"
198 JA QSOs on 10m, spread across hours, peak Oct-Dec
15m — Reliable DX
15m Japan — Afternoon Open
hard"Trans-Pacific F2, reliable high-band DX path"
301 QSOs DN46→PM95 on 15m, peak at 17z, peak month Oct
15m EU Path — Daytime Open
hard"Transatlantic F2, afternoon MT, evening EU, band open"
568 EU QSOs on 15m, hours 14-22z
20m — Workhorse
20m EU Path — Daytime Open
hard"20m workhorse DX band, F2 refraction, reliable year-round"
1,760 EU QSOs on 20m, all hours, peak in winter
40m — Night DX
40m Japan — Night Open
hard"40m night path, F2 skip at lower frequency, MT darkness + JA morning"
585 JA QSOs on 40m, hours 5-15z, peak Oct
80m — Domestic Night
80m Domestic Night — Open
hard"80m NVIS/1-hop skip, mutual darkness, domestic range"
69 QSOs DN46→CN87 on 80m, peak at 04z, Nov
80m Domestic Day — Dead
hard"D-layer absorption kills 80m in daylight. 5 QSOs in 16 years = physics, not habits."
5 daytime QSOs on 80m in KI7MT log. Contest: 80m NA domestic at 14-15z = 141 sigs vs 02-04z = 57,207 sigs (400:1 ratio).
160m — Top Band
160m Domestic Night — Open
hard"160m requires mutual darkness, winter nights, low D-layer absorption"
76 QSOs DN46→CN87 on 160m, peak at 04z, Feb
160m Domestic Day — Dead
hard"Complete D-layer absorption at 1.8 MHz in daylight. Physics, not habits."
0 QSOs 16-20z on 160m in KI7MT log. Contest: 160m NA domestic at 13-20z = 11 sigs vs 00-05z = 16,878 sigs (1,500:1 ratio).
160m Japan — Deep Night DX
hard"160m trans-Pacific, mutual darkness window, low Kp critical"
43 JA QSOs on 160m, hours 9-15z, Jan peak. Rare but real.
160m Summer — Dead Season
soft"Summer nights too short for 160m propagation, atmospheric noise dominant. Possibly also antenna/operating habits."
0 QSOs on 160m in Mar-Oct. Likely physics (short nights, high noise) but operator may not have had 160m antenna year-round.
Band Ordering — The Physics Test
Band Order — Day (high > low)
hard"High bands dominate in daylight (F2 ionization). Low bands absorbed (D-layer)."
Daytime QSO counts: 10m=3505, 15m=6612, 20m=13877, 40m=1729, 80m=5, 160m=135
Band Order — Night (low > high)
hard"Low bands dominate at night (no D-layer, F2 still present for NVIS). High bands dead."
Night QSO counts: 160m=2434, 80m=1949, 40m=8119, 20m=3923, 15m=430, 10m=128
About These Tests
These 18 paths are derived from KI7MT's 49,233 QSOs (2009-2025) cross-validated against 5.7 million contest signatures from 234 million CQ contest QSOs.
Hard gates are physics-dictated: the path either works or it doesn't, regardless of operating habits. 10m transatlantic at 2 AM is impossible — F2 layer has collapsed.
Soft gates allow for operating habits — zero QSOs on 160m in summer might be antenna limitations, not physics.
V22-gamma (production model) scores 16/17 hard pass. The one failure: KI7MT-005 (10m EU night) — the acid test.