This WSPR test of the Yaesu ATAS-120A was carried out from the same location as the previous one, this time in hot and sunny weather. The goal was to check how repeatable the results were and to see how the current conditions affected the antenna’s performance.
The test started with the same setup as before, using only a single 10 m coaxial cable connected directly to the antenna. This served as the reference configuration for all further measurements.
Next, I inserted a 2.8 m coaxial cable using a UHF-to-UHF barrel connector. The connector was grounded using a homemade copper ground rod. After the connector, the original 10 m coaxial cable was connected back to the radio. In practice, I didn’t notice any measurable difference in the WSPR results or overall antenna performance.
Finally, I connected the Yaesu FT-857D chassis to a second copper ground rod using a 2 m grounding cable. This resulted in a small improvement in SWR. For example, on the 10 m band, the SWR dropped from about 1.3 to 1.1.
Overall, the SWR on the 20 m to 10 m bands remained between 1.0 and 1.5, so it wasn’t really a concern. Unfortunately, I couldn’t get the SWR below 2.5 on the 40 m band, as shown below.
10m (28 MHz)
Top 6 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | V51RS | Namibia | JG87QL | −23 dB | 8,076 km |
| 2 | OH6BG | Finland | KP03QA | −6 dB | 1,500 km |
| 3 | GM4WJA | Scotland | IO87MN | −27 dB | 1,409 km |
| 4 | OH3LMN/KIWI | Finland | KP11WM | −13 dB | 1,400 km |
| 5 | SM3LNM | Sweden | JP82QG | −14 dB | 1,369 km |
| 6 | LA3FY/2 | Norway | JP40FJ | −28 dB | 1,209 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | OH6BG | Finland | −6 dB |
| 2 | OH3LMN/KIWI | Finland | −13 dB |
| 3 | SM3LNM | Sweden | −14 dB |
| 4 | V51RS | Namibia | −23 dB |
| 5 | GM4WJA | Scotland | −27 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 11
Longest DX: V51RS (Namibia) – 8,076 km
Best Reception Report: −6 dB from OH6BG (Finland)
Coverage: The 10 m band was mostly closed during the test, with only 11 WSPR spots received. Despite the limited activity, one exceptional long-distance reception from Namibia reached 8,076 km, indicating a brief opening on the band.
12m (28 MHz)
Top 10 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | 5Z4GO | Kenya | KI96UA | −22 dB | 6,479 km |
| 2 | HZ1SF | Saudi Arabia | LL34HQ | −24 dB | 3,949 km |
| 3 | OH6BG | Finland | KP03QA | +2 dB | 1,500 km |
| 4 | M9PSY | Northern Ireland | IO86HA | −17 dB | 1,358 km |
| 5 | M9PSY-1 | Northern Ireland | IO86HA | −17 dB | 1,358 km |
| 6 | OH3MZT | Finland | KP10 | −20 dB | 1,275 km |
| 7 | ES2RR | Estonia | KO29HG | −18 dB | 1,212 km |
| 8 | LA3FY/2 | Norway | JP40FJ | −10 dB | 1,209 km |
| 9 | SM4JST/RX1 | Sweden | JO79KR | −16 dB | 1,075 km |
| 10 | SA1CKE | Sweden | JO97HN | −20 dB | 877 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | OH6BG | Finland | +2 dB |
| 2 | LA3FY/2 | Norway | −10 dB |
| 3 | SM4JST/RX1 | Sweden | −16 dB |
| 4 | M9PSY | Northern Ireland | −17 dB |
| 5 | M9PSY-1 | Northern Ireland | −17 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 19
Longest DX: 5Z4GO (Kenya) – 6,479 km
Best Reception Report: +2 dB from OH6BG (Finland)
Coverage: Although the number of spots was relatively low, the 12 m band produced some impressive DX, including Kenya and Saudi Arabia. Most receptions came from northern and central Europe, with a brief opening towards East Africa and the Middle East.
15m (21 MHz)
Top 10 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | VK8TH | Australia | PH57NJ | −22 dB | 12,970 km |
| 2 | K9CZI | USA | CN83MW | −17 dB | 8,779 km |
| 3 | K9IMM | USA | EN52CV | −24 dB | 7,343 km |
| 4 | K9TRV | USA | EN82BI | −21 dB | 7,049 km |
| 5 | K9TRV-4 | USA | EN82BI | −20 dB | 7,049 km |
| 6 | K9TRV-5 | USA | EN82BI | −21 dB | 7,049 km |
| 7 | KD2OM | USA | FN12GX | −25 dB | 6,620 km |
| 8 | WA2TP | USA | FN30LU | −27 dB | 6,503 km |
| 9 | 5Z4GO | Kenya | KI96UA | −22 dB | 6,479 km |
| 10 | KQ2Y | USA | FN31GN | −25 dB | 6,478 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | SK6WW | Sweden | +2 dB |
| 2 | OH6BG | Finland | 0 dB |
| 3 | EA8/DF4UE | Canary Islands | −8 dB |
| 4 | SA6BSS/HL | Sweden | −8 dB |
| 5 | OH3LMN/KIWI | Finland | −9 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 81
Longest DX: VK8TH (Australia) – 12,970 km
Best Reception Report: +2 dB from SK6WW (Sweden)
Coverage: The 15 m band delivered excellent results, with 81 WSPR spots and outstanding long-distance propagation. Besides strong coverage across Europe, signals reached Australia, Kenya, and multiple stations across North America, with the longest reception coming from Australia at nearly 13,000 km.
17m (18 MHz)
Top 10 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | VK8TH | Australia | PH57NJ | −24 dB | 12,970 km |
| 2 | K6VZK | USA | DM13NH | −22 dB | 9,582 km |
| 3 | V51RS | Namibia | JG87QL | −24 dB | 8,076 km |
| 4 | KD2OM | USA | FN12GX | −16 dB | 6,620 km |
| 5 | WA2TP | USA | FN30LU | −23 dB | 6,503 km |
| 6 | N2YCH | USA | FN31JG | −25 dB | 6,483 km |
| 7 | KQ2Y | USA | FN31GN | −23 dB | 6,478 km |
| 8 | VE3CWM | Canada | FN15XI | −28 dB | 6,361 km |
| 9 | W1XP | USA | FN42FO | −23 dB | 6,282 km |
| 10 | KM3T-3 | USA | FN42ET | −25 dB | 6,272 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | G8OCV/SDR | England | +1 dB |
| 2 | WESSEX | England | 0 dB |
| 3 | SQ3H | Poland | 0 dB |
| 4 | OH3MZT | Finland | −4 dB |
| 5 | OZ1BFM | Denmark | −5 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 257
Longest DX: VK8TH (Australia) – 12,970 km
Best Reception Report: +1 dB from G8OCV/SDR (England)
Coverage: The 17 m band delivered excellent propagation throughout the test, producing 257 WSPR spots. In addition to strong coverage across Europe, signals reached Australia, Namibia, Canada, and several stations across the United States, with the longest reception coming from Australia at 12,970 km.
20m (14 MHz)
Top 10 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | WA2TP | USA | FN30LU | −25 dB | 6,503 km |
| 2 | HZ1SF | Saudi Arabia | LL34HQ | −21 dB | 3,949 km |
| 3 | EA8BFK | Canary Islands | IL38BO | −23 dB | 3,372 km |
| 4 | EA8/DF4UE | Canary Islands | IL38BP | −19 dB | 3,368 km |
| 5 | 4Z4TJ | Israel | KM71JF | −13 dB | 2,689 km |
| 6 | CR7CDF | Portugal | IM58NM | −27 dB | 2,242 km |
| 7 | TA4/G8SCU | Türkiye | KM56VO | −23 dB | 2,041 km |
| 8 | EC1CS | Spain | IN62BI | −26 dB | 1,910 km |
| 9 | SM2LTA | Sweden | JP94AT | −21 dB | 1,653 km |
| 10 | TA3AWF | Türkiye | KM38IJ | −28 dB | 1,619 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | ON5KQ | Belgium | +5 dB |
| 2 | EI4HQ | Ireland | +1 dB |
| 3 | G6MC/K | England | 0 dB |
| 4 | G4ZFQ | England | −3 dB |
| 5 | WESSEX | England | −4 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 438
Longest DX: WA2TP (USA) – 6,503 km
Best Reception Report: +5 dB from ON5KQ (Belgium)
Coverage: The 20 m band delivered the highest activity of the entire test, producing 438 WSPR spots. Propagation was excellent across Europe, with numerous strong reception reports, while reliable DX paths reached North America, the Canary Islands, the Middle East, Portugal, Spain, and Türkiye. Although the maximum distance was shorter than on the higher HF bands, 20 m clearly provided the most stable and consistent propagation throughout the test, making it the best-performing band overall.
40m (7MHz)
The 40 m band proved to be the most challenging during this test. The best result achieved was an SWR of approximately 2.5, using the original WiMo elevated radials, the ground stake system described earlier, and four additional 15 m wire radials (0.75 mm² PVC-insulated wire) connected at the antenna feed point approximately 2 m above ground. Removing the WiMo radials increased the minimum SWR to about 3.0, while shortening the wire radials by folding them back only made the match worse. Further experimentation with the radial system will therefore be required.
Top 10 Longest-Distance Receptions
| # | Callsign | Country | Grid Locator | SNR | Distance |
|---|---|---|---|---|---|
| 1 | EI4HQ | Ireland | IO51UU | −30 dB | 1,599 km |
| 2 | OH6BG | Finland | KP03QA | −6 dB | 1,500 km |
| 3 | OH6AH | Finland | KP12KR | −7 dB | 1,498 km |
| 4 | OH3LMN/KIWI | Finland | KP11WM | −9 dB | 1,400 km |
| 5 | M9PSY | Northern Ireland | IO86HA | −24 dB | 1,358 km |
| 6 | M9PSY-1 | Northern Ireland | IO86HA | −24 dB | 1,358 km |
| 7 | M9PSY-2 | Northern Ireland | IO86HA | −25 dB | 1,358 km |
| 8 | F4FPR | France | IN88DI | −24 dB | 1,330 km |
| 9 | ES4O | Estonia | KO39DC | −18 dB | 1,258 km |
| 10 | WESSEX | England | IO80QR | −7 dB | 1,211 km |
Top 5 Strongest Reception Reports
| # | Callsign | Country | SNR |
|---|---|---|---|
| 1 | OE3GBB | Austria | +15 dB |
| 2 | LX1LC | Luxembourg | +9 dB |
| 3 | DC5AL-R | Germany | +7 dB |
| 4 | DL4ZBE | Germany | +7 dB |
| 5 | OZ7IT | Denmark | +5 dB |
Summary
Transmit Power: 5 W
Total WSPR Spots: 282
Longest DX: EI4HQ (Ireland) – 1,599 km
Best Reception Report: +15 dB from OE3GBB (Austria)
Coverage: Despite the relatively poor antenna match on 40 m, the antenna still generated 282 WSPR spots across much of central, northern and western Europe. No intercontinental propagation was observed on this band during the test, but regional coverage was excellent, demonstrating that the ATAS-120A remains usable on 40 m even with an SWR of around 2.5. Further optimisation of the elevated radial system should improve both the impedance match and overall performance.
Overall WSPR Coverage
The map below shows the overall reception coverage achieved during the test. The vast majority of reception reports shown were obtained during the 5 W WSPR measurements described in this article. Some additional markers may originate from separate 10 W FT8 activity performed during the same period.
Even so, the map clearly demonstrates the excellent coverage achieved with the portable ATAS-120A setup, reaching stations throughout Europe, North America, Africa, the Middle East, Asia, and Australia.
OK1TK HAM Radio 