Grid GG77 Band Conditions — Rio de Janeiro
Localized HF conditions for Maidenhead locator GG77. Coordinating at -22.50°, -45.00°. Updated with real-time telemetry from NOAA and DX cluster reports.
GG77 conditions are GOOD. Best bands: 10m, 12m, 15m, 17m, 20m. SFI: 137.
From Rio de Janeiro, work the 09:39 UTC and 20:35 UTC grayline windows: probe 20m, 30m, and 40m in the 15 minutes either side while the terminator crosses GG77.
10m is the headline band right now, with 20m as the dependable fallback if conditions soften.
This square sits in South America footprint and is best used as a planning center for portable, field-day, and home-station band decisions.
- Latitude zone
- tropical
- Local phase
- Daylight
- Aurora exposure
- low at this latitude
- Grayline
- 09:39 UTC / 20:35 UTC
- Best high band
- 10m
- Nearest city
- Rio de Janeiro
● Local Band Quality Scorings
Use this local score for GG77, then compare the global live ranking oncurrent ham band conditionsbefore changing bands.
● Best DX Windows from GG77 — Rio de Janeiro
Great-circle distance, short-path beam heading, the bands most likely open right now from GG77 to each DX region at SFI 137 / Kp 2, and a current verdict. "Open now" means a suitable band is scoring well on that path; "Try ~HH:MM" points at the next far-end grayline. Band picks and status are a planning heuristic, not a measurement.
| Target | Distance | Beam | Bands to try | Status |
|---|---|---|---|---|
| Southern Africa | 4,423 mi | 109° | 10m, 15m, 20m | Open now |
| North America | 5,457 mi | 321° | 10m, 15m, 20m | Open now |
| Europe | 6,030 mi | 32° | 10m, 15m, 20m | Open now |
| Oceania | 8,675 mi | 196° | 10m, 15m, 20m | Open now |
| South Asia | 8,815 mi | 79° | 40m, 20m, 80m | Open now |
| East Asia / Japan | 11,487 mi | 350° | 10m, 15m, 20m | Open now |
● Band-by-Time Plan for GG77
A planning heuristic for the local day at GG77, built from sunrise 09:39 UTC, sunset 20:35 UTC, SFI 137, and Kp 2. Not a measurement — a starting point for where to listen as the day turns.
Grayline enhancement — low bands reach long distances as the terminator passes.
High bands rising with the sun; check 10m for DX.
Peak high-band window — 10m and 15m open widest.
Second grayline peak — 20m holds, then hands off to 40m.
Low bands own the darkness — 40m for DX, 80m regional.
Recent local activity
Spots touching GG77 and the adjacent squares
These are the newest 10m, 15m, and 20m reports where one side of the path sits in GG77, GG78, GG76, GG87, GG67. This gives the page unique, local context instead of a generic solar snapshot.
Top DX targets
Where this grid is reaching right now
Contest preview
Next major contest outlook
No contest event is currently loaded. For planning from GG77, start with 10m EXCELLENT, 15m EXCELLENT, 20m GOOD and keep 20m available as the safest all-around fallback.
Open contest calendarNearby grids