Free antenna length calculator for amateur radio operators. Enter any HF frequency and instantly get wire lengths for the most common antenna designs: quarter-wave vertical, 5/8λ vertical, half-wave dipole, end-fed half-wave (EFHW), end-fed random wire (EFRW), off-centre-fed dipole (OCF) and the KJ6ER-style OCF vertical. Widely used by hams across Spain and IARU Region 1 for portable QRP operations, field days and antenna construction.
Antenna Dimensions
Enter a frequency to get the wire lengths for common antenna types.
Great-circle beam heading and distance calculator for amateur radio. Enter two Maidenhead grid squares to get the short-path and long-path bearings in degrees, plus the distance in kilometres and miles. Essential for pointing a Yagi, log-periodic or directional antenna toward a DX station or for planning portable activations from Spain and across Europe.
Beam Heading & Distance
Great-circle bearing and distance between two Maidenhead grid squares.
Maidenhead grid square converter for amateur radio. Convert a 4- or 6-character Maidenhead locator (e.g. IN73dm) to decimal latitude and longitude, or derive your grid square from GPS coordinates. Indispensable for POTA, SOTA and IOTA activations, VHF/UHF contest logging, FT8/FT4 QSOs and satellite passes. Includes an interactive map preview.
Grid Square Converter
Convert between Maidenhead locator and decimal lat/lon.
IARU Region 1 HF band plan — the official frequency allocation reference for amateur radio operators in Europe, Africa and the Middle East, including Spain. Covers 160m through 23cm with CW, SSB, digital (FT8, WSPR, PSK31, RTTY), beacon and satellite segments. Based on the IARU R1 2016 plan. Use this as a quick reference when operating CW or SSB from Spain, planning a portable activation, or checking whether a frequency is within the correct mode segment.
IARU Region 1 — HF Band Plan
Simplified reference for Europe / Africa / Middle East. Based on IARU R1 2016 plan.
| From (MHz) | To (MHz) | Mode / Usage | Notes |
|---|
RST signal report scale and Q-code reference for amateur radio operators. The RST system — Readability, Signal strength and Tone — is the standard used worldwide for CW, SSB and digital contacts. The searchable Q-code table covers the most common ITU abbreviations used in on-air operating: QRZ, QSL, QTH, QRP, QRN, QRM and more. An essential quick reference for both new hams and experienced operators in Spain and across IARU Region 1.
RST Scale & Q-Codes
Signal reporting and the most common operating abbreviations.
Readability (R)
| # | Meaning |
|---|---|
| 1 | Unreadable |
| 2 | Barely readable, occasional words distinguishable |
| 3 | Readable with considerable difficulty |
| 4 | Readable with practically no difficulty |
| 5 | Perfectly readable |
Signal Strength (S)
| # | Meaning |
|---|---|
| 1 | Faint signals, barely perceptible |
| 2 | Very weak signals |
| 3 | Weak signals |
| 4 | Fair signals |
| 5 | Fairly good signals |
| 6 | Good signals |
| 7 | Moderately strong signals |
| 8 | Strong signals |
| 9 | Extremely strong signals |
Tone (T) — CW only
| # | Meaning |
|---|---|
| 1 | Extremely rough, hissing note |
| 3 | Rough AC note, slightly musical |
| 5 | Musically modulated note |
| 7 | Near DC note, slight trace of ripple |
| 9 | Perfect DC note — pure tone |