(Last updated: Dec. 2, 2018)
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RECOMMENDED VIDEO
S Units
https://www.blubrry.com/arrl_the_doctor_is_in/25197956/s-units/
Released August 17, 2017
QRP
https://www.blubrry.com/arrl_the_doctor_is_in/27798351/qrp/
Released October 26, 2017
At 11:20, they mentioned me !!!
Comparison of Signal Strength:
My signals received and recorded by SM4OTI on October 9, 2011, 1010UTC, on 24MHz, CW. Thanks to Steve.
Great ears !!0:00 - 0:41: My output power 10W
1:03 - 1:18: My output power 500mW (0.5W)
1:43 - 2:00: My output power 200mW (0.2W)
MY ANTENNA: a dipole on my balcony about 20mH
Given that 1 S-unit corresponds to 6dB:
(Note: The actual propagations may not follow the linear relationship shown in the above graph.)
(Note: The actual propagations may not follow the linear relationship shown in the above graph.)
S9 ON YOUR S-METER:
If the other end of the QSO is running 1 kW and it yields S9 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 1 kW gives S9 on the S-meter at the other end,
your 250 W gives S8 on the S-meter at the other end,
your 62.5 W gives S7 on the S-meter at the other end,
your 15.6 W gives S6 on the S-meter at the other end,
your 3.9 W gives S5 on the S-meter at the other end,
your 0.98 W gives S4 on the S-meter at the other end,
your 0.24 W gives S3 on the S-meter at the other end.
If the other end of the QSO is running 100 W and it yields S9 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 100 W gives S9 on the S-meter at the other end,
your 25 W gives S8 on the S-meter at the other end,
your 6.25 W gives S7 on the S-meter at the other end,
your 1.56 W gives S6 on the S-meter at the other end,
your 0.39 W gives S5 on the S-meter at the other end,
your 0.097 W gives S4 on the S-meter at the other end,
your 0.024 W gives S3 on the S-meter at the other end.
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 1 kW gives S9 on the S-meter at the other end,
your 250 W gives S8 on the S-meter at the other end,
your 62.5 W gives S7 on the S-meter at the other end,
your 15.6 W gives S6 on the S-meter at the other end,
your 3.9 W gives S5 on the S-meter at the other end,
your 0.98 W gives S4 on the S-meter at the other end,
your 0.24 W gives S3 on the S-meter at the other end.
If the other end of the QSO is running 100 W and it yields S9 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 100 W gives S9 on the S-meter at the other end,
your 25 W gives S8 on the S-meter at the other end,
your 6.25 W gives S7 on the S-meter at the other end,
your 1.56 W gives S6 on the S-meter at the other end,
your 0.39 W gives S5 on the S-meter at the other end,
your 0.097 W gives S4 on the S-meter at the other end,
your 0.024 W gives S3 on the S-meter at the other end.
S3 ON YOUR S-METER:
If the other end of the QSO is running 1 kW and it yields S3 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 1 kW gives S3 on the S-meter at the other end,
your 250 W gives S2 on the S-meter at the other end,
your 62.5 W gives S1 on the S-meter at the other end,
your 15.6 W gives S0 on the S-meter at the other end.
your 0.5 W gives S ? on the S-meter at the other end.
If the other end of the QSO is running 100 W and it yields S3 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 100 W gives S3 on the S-meter at the other end,
your 25 W gives S2 on the S-meter at the other end,
your 6.25 W gives S1 on the S-meter at the other end,
your 1.56 W gives S0 on the S-meter at the other end.
your 0.5 W gives S ? on the S-meter at the other end.
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 1 kW gives S3 on the S-meter at the other end,
your 250 W gives S2 on the S-meter at the other end,
your 62.5 W gives S1 on the S-meter at the other end,
your 15.6 W gives S0 on the S-meter at the other end.
your 0.5 W gives S ? on the S-meter at the other end.
If the other end of the QSO is running 100 W and it yields S3 on your S-meter, and
if the transmitting propagation path and the receiving propagation path are equivalent (although they may not be actually equivalent),
then
your 100 W gives S3 on the S-meter at the other end,
your 25 W gives S2 on the S-meter at the other end,
your 6.25 W gives S1 on the S-meter at the other end,
your 1.56 W gives S0 on the S-meter at the other end.
your 0.5 W gives S ? on the S-meter at the other end.
Using your 0.5 W (500 mW), is it possible to work non-QRP stations showing S3 or less on your S-meter ?
UNEXPECTED RESULTS:
The following list shows my QRPp QSOs with stations showing S3 or less on my S-meter (i.e. stations whose signal strength "S" was not more than 3 on my S-meter).
These are exceptional rare cases, but these unexpected and surprising QSOs are actually possible.
Thanks to the great-ears stations in the list for receiving my weak signals.
Great ears !!
My Rig: ICOM IC-7000S
My Output Power: 0.5 W (500mW) except for 3DA0ZO
My Antenna: Dipole
Mode: CW
The "S" was measured on the S-meter of my IC-7000S with the preamp on.
"S 0-3" means S0 to S3 with QSB.
............................................................................
My PWR(watts) /Band(m) /Mode /Date(d,m,y) /Call /(His/Her "S" on my S-meter)
............................................................................
"*" after Call means that the QSO has been confirmed by a QSL card, LoTW, eQSL or his log.
............................................................................
S 0-1 on my S-meter:
0.5 17M CW 27 MAY 2008 XX9TCC *(Macao)(S:0-1)
0.5 15M CW 10 NOV 2008 5B4AIZ *(Cyprus)(S:0-1)
0.5 12M CW 03 MAY 2012 YJ0VK *(Vanuatu)(S:0-1)
0.5 12M CW 02 NOV 2013 3D2KV *(Fiji Is.)(S:0-1)(My 2 calls)
S 1 on my S-meter:
10 15M CW 25 NOV 2007 3DA0ZO *(Swaziland)(S:1)(My power was 10W, not QRPp)
0.5 17M CW 26 JAN 2008 3D2AG/P *(Rotuma I.)(S:1)
0.5 17M CW 27 FEB 2008 DU9/DK2PR (S:1)
0.5 17M CW 12 FEB 2009 FW5RE *(Wallis & Futuna Is.)(S:1)
0.5 12M CW 21 SEP 2011 CF7AAW (S:1)
0.5 10M CW 04 DEC 2011 BW/N3QQ (AS-102)(S:1)
S 0-2 on my S-meter:
0.5 15M CW 14 OCT 2007 ZL1TM *(S:0-2)
0.5 17M CW 27 MAY 2008 HS0ZBS *(S:0-2)
0.5 17M CW 03 NOV 2008 YJ0AQY *(Vanuatu)(S:0-2)
0.5 10M CW 25 SEP 2012 N0AC * (CO)(S:0-2)
S 1-2 on my S-meter:
0.5 15M CW 25 SEP 2007 VK9WWI *(Willis I.)(S:1-2)
0.5 17M CW 06 MAY 2011 GW0ETF *(Wales)(S:1-2)
0.5 12M CW 06 NOV 2013 E6AK (Niue)(S:1-2)
0.5 12M CW 28 OCT 2014 V73NS *(S:1-2)
S 2 on my S-meter:
0.5 17M CW 26 JAN 2008 VK9NS (Norfolk I.)(S:2)
0.5 17M CW 06 MAY 2011 P29CW *(S:2)
0.5 12M CW 24 SEP 2011 4W6A *(East Timor)(S:2)
0.5 12M CW 26 SEP 2011 V85SS (S:2)
0.5 10M CW 18 OCT 2011 KF4GDX *(SC; The East Coast)(S:2)
0.5 10M CW 26 NOV 2011 K7SS *(WA)(S:2)
S 0-3 on my S-meter:
0.5 17M CW 06 OCT 2009 3D20CR *(Conway Reef)(S:0-3)
0.5 10M CW 16 OCT 2012 ZP6CW *(Paraguay)(S:0-3)(My 2 calls)
S 1-3 on my S-meter:
0.5 17M CW 09 NOV 2008 RU450WW *(S:1-3)
0.5 10M CW 11 DEC 2011 US8UA *(S:1-3)
0.5 17M CW 26 JUN 2012 OH0/OK2BOB *(Aland Is.)(S:1-3)
0.5 10M CW 20 OCT 2012 T88EC (S:1-3)(My 1 call)
0.5 10M CW 24 OCT 2012 EA8/DL3FCG *(Canary Is.)(S:1-3)
0.5 12M CW 08 NOV 2012 SG0U *(EU-084)(S:1-3)
0.5 17M CW 26 MAY 2018 RI1FJ *(Franz Josef Land)(S:1-3)
S 2-3 on my S-meter:
0.5 17M CW 22 SEP 2009 T2G *(Tuvalu)(S:2-3)
0.5 17M CW 01 MAY 2011 GB5TI *(Scotland; EU-108)(S:2-3)
0.5 12M CW 09 OCT 2011 9A3SM *(S:2-3)
0.5 10M CW 19 OCT 2011 T32C *(East Kiribati)(S:2-3)
0.5 10M CW 20 OCT 2012 EI3KG *(Ireland)(S:2-3)(My 2 calls)
0.5 10M CW 22 OCT 2012 HG90ST *(S:2-3)
0.5 12M CW 08 NOV 2012 OE5NNN (S:2-3)
0.5 17M CW 29 NOV 2013 5W8A *(Samoa Is.)(S:2-3)
S 3 on my S-meter:
0.5 17M CW 14 DEC 2006 KH8Q *(American Samoa)(S:3)
0.5 15M CW 25 NOV 2007 VK2PN *(S:3)
0.5 17M CW 29 FEB 2008 EY1HQ (Tajikistan)(S:3)
0.5 17M CW 12 FEB 2009 3D2NB *(Fiji Is.)(S:3)
0.5 17M CW 03 OCT 2009 SG3U *(S:3)
0.5 17M CW 15 OCT 2009 E51NOU *(South Cook Is.)(S:3)
0.5 12M CW 21 NOV 2009 ZL1BYZ *(S:3)
0.5 12M CW 21 APR 2011 UK8OM (Uzbekistan)(S:3)
0.5 10M CW 21 APR 2011 3D2AD *(Fiji Is.)(S:3)
0.5 15M CW 25 APR 2011 V85AN (S:3)
0.5 17M CW 15 JUN 2011 UQ40I (Kazakhstan)(S:3)
0.5 17M CW 19 JUN 2011 F5UOW/P *(EU-032)(S:3)
0.5 17M CW 12 JUL 2011 HA8QZ/P (S:3)
0.5 12M CW 25 SEP 2011 OZ1CTK *(S:3)
0.5 12M CW 25 SEP 2011 KQ7W *(WA)(S:3)
0.5 12M CW 26 SEP 2011 F5PLC *(S:3)
0.5 12M CW 26 SEP 2011 XU7SSB (Cambodia)(S:3)
0.5 12M CW 01 OCT 2011 T32C *(East Kiribati)(S:3)
0.5 12M CW 09 OCT 2011 OJ0X *(Market Reef)(S:3)
0.5 10M CW 18 OCT 2011 F8GDP *(S:3)
0.5 10M CW 21 OCT 2011 ZL4RUGBY *(S:3)
0.5 10M CW 26 OCT 2011 LW2DOD *(Argentina)(S:3)
0.5 10M CW 09 NOV 2011 YN7SU *(Nicaragua)(S:3)
0.5 10M CW 13 NOV 2011 OK1AD *(S:3)
0.5 10M CW 13 NOV 2011 OK1IE *(S:3)
0.5 10M CW 14 NOV 2011 DL60ZBN (S:3)
0.5 12M CW 16 NOV 2011 DQ1175E *(S:3)
0.5 10M CW 19 NOV 2011 RA1AL *(S:3)
0.5 10M CW 20 NOV 2011 R2AB *(S:3)
0.5 10M CW 20 NOV 2011 RZ8U *(S:3)
0.5 10M CW 26 NOV 2011 LT1F *(Argentina)(S:3)
0.5 10M CW 26 NOV 2011 VE7IO *(S:3)
0.5 10M CW 01 DEC 2011 UP20IT (Kazakhstan)(S:3)
0.5 10M CW 02 DEC 2011 UP20GW *(Kazakhstan)(S:3)
0.5 10M CW 11 DEC 2011 EX2B *(Kyrgyzstan)(S:3)
0.5 12M CW 06 OCT 2013 LA2MOA *(EU-141)(S:3)
0.5 12M CW 07 OCT 2013 FK8DD/M *(mobile, New Caledonia)(S:3)
0.5 15M CW 24 MAY 2014 E51KJW (South Cook Is.)(S:3)
My QRPp Policy:
I use an output power of 500 milliwatts (0.5W) to call a target DX station.
In "599 BK"-style QSOs, I maintain my output power at 500 milliwatts until completion of the QSOs.
In non-"599 BK" style QSOs, after confirming that my callsign has been correctly copied and after sending his/her RST at 500 milliwatts, I sometimes increase my power to 5 watts or 10 watts (my maximum power) to send my name, QTH, RIG, ANT, WX, etc., depending on the band conditions.
I consider the contact as a QRPp contact at 500 milliwatts.
In some contests, etc., I sometimes use 5 watts or 10 watts for calling.
HOME
............................................................................
My PWR(watts) /Band(m) /Mode /Date(d,m,y) /Call /(His/Her "S" on my S-meter)
............................................................................
My QRPp Policy:
I use an output power of 500 milliwatts (0.5W) to call a target DX station.
In "599 BK"-style QSOs, I maintain my output power at 500 milliwatts until completion of the QSOs.
In non-"599 BK" style QSOs, after confirming that my callsign has been correctly copied and after sending his/her RST at 500 milliwatts, I sometimes increase my power to 5 watts or 10 watts (my maximum power) to send my name, QTH, RIG, ANT, WX, etc., depending on the band conditions.
I consider the contact as a QRPp contact at 500 milliwatts.
In some contests, etc., I sometimes use 5 watts or 10 watts for calling.
HOME