zaterdag 24 mei 2014

QRPpp eQSLs

Here are some eQSLs' from the last batch.
The QSO's are all made QRPpp using the Lowest Possible Power.
QRPpp is the (not official) term, that I use for a power of less than 100 milliwatts.
Also known as two digit milliwatting.

Making QSO's with very  low power is not that difficult.
It´s all a matter of propagation.
The changes in propagation can be hugh.
So when the S-meter goes 20 dB up, the power can be reduced with 20 dB.

Look for a CQ of a station with an earsplitting S++ signal.
Answer with low power, with the excellent timing that you always use.
Don´t suspect anything, but be prepared after you give your call.
Most of the time, other stations are answered.
But than suddenly, the frequency is clear and you will be heard.
It´s possible that you are surprised, that you hear your call, being send immediately correct.
And before you know it, you also get an exchange. What was that? What number did he gave? hi.

9H1XT    1205 Miles   3.6 mW   334841 Miles per Watt

IV3ZXQ   550 Miles   22 mW   25002 MPW

SM5QU   740 Miles   36 mW   20549 Miles per Watt

SV1ENG   1318 Miles   98 mW   13453 Miles per Watt

S56M   588 Miles   80 mW   7349 Miles per Watt

OE2008S   445 Miles   98 mW   4698 Miles per Watt
See me smile from ear to ear after such a QSO.  

woensdag 21 mei 2014

Notes from the SP DX contest

I never use a fixed power, but adjust my power from QSO to QSO.
Before I answer the CQ, I adjust my power to:  500 mW,  1 W, 2.5 watts or 5 watts.
If the signal is very strong, I use the S-meter to determine the power that I wil use.
For example: a signal of:  S+ + 10 dB, I can answer with 50 mW,
To make such a low power I use an attenuator of 10 dB.

To enter the call or write down  the call and to set the power at the same time, is impossible,
So I am always too late for the first opportunity to answer.
And sometimes, I even switch to the wrong setting, which can be to low or to high. hi

Using the lowest possible power is great fun, but can also be a nerve wracking enterprise.

Interesting Experiences      Wow's and Woo's from my handwritten notes, made during the SP DX 2014
* In the QSO with SP8HW I realized that listening is very important.
    When I started to answer a CQ, I heard an other station answering, in the background.
    When he stopped, I gave my call twice, in the clear and made the QSO with 500 mW.
* I worked 3Z50AYP in a hurry. I was so excited, that I used 500 mW instead of a lower power.
    After the QSO it was quiet on the frequency. But a dupe will be impossible. ;-(
* SP6EIY can not hear me with 500 mW and 1 W. Maybe later.
* I seized the opportunity to switch back to 500 mW, while waiting  for a very loud station.
    It's important to immediately adjust to 500 mW, after a QSO with 1 W or 5 W.
* I had to push to make a QSO with SP2GJV with just 50 mW, which is quite remarkable.
    There was a lot of QRM in the background.
* Station after station, visited SP3FYX.
    I had to have a lot of patience, not to increase the power to 5 watts.
    And finaly, to use just 500 mW.
* I love chirpping stations. I work SP7.... with 5W.
* Worked SP9YFF with 500 mW, before I got the call complete.
    I realized that . . . FF was a new one.
* After the QSO with SN8N, I realize that I should have used 50 mW instead of 500 mW.
    The signal was earsplitting loud. S++
* One station after the other goes in to the log. It 's a mix of 500 mW and 5 W.
* It's very busy. I have to look for stations that are calling CQ with no takers.
* SP6ZDA At the last moment, I decide to switch in the 10 dB attenuator.
    Resulting in a QSO in the clear, with just 50 mW.
* Now I recognize new stations by the last letters of the call.
* 3Z8Z fades. I need 5 W.
* The numbers of my computer program and the Morse Machine differ.
    I correct the Morse Machine.
* SP9MZS Earsplitting signal. But the setting is wrong, so 500 mW instead of 50 mW.
    Next time better.

    I could make all these fine QSO's, thanks to all the fine operators in the from Poland.

maandag 12 mei 2014

eQSL avalanche

Last week the number of eQSLs in my eQSL inbox had risen to more than 100.
Between these QSLs were many 1000 Miles per Watt QSL's.
For these QSL's, I determine the distance and calculate the Miles/Watt.
I mention these numbers in the comment field of the individual eQSL.

Last week I replied many eQSL's.
  F6KDF  435 Miles and 8.5 mW gives 51128 Miles/Watt
It took me a few days, to reply manually,
on the eQSL site.
So I was glad, that I had reduced that number
to about 10 remaining eQSLs.

But when opened my eQSL inbox a few days later, it knocked my socks off.
There were 208 eQSL's in my inbox.
This number is very large to reply manually.

A doubling in a couple of days.
And what if that number doubles again?

donderdag 8 mei 2014

G4ILO Whispering with 20 mW and 1 mW

This is an other analysis of the data collected from the
WSPR database for spots of Julian G4ILO.
Julian transmitted with a power of 1 mW and 20 mW.

The table shows, that the spots that were made with 1 mW, 
were about 10 dB weaker than the spots made with 20 mW

The table shows a selection stations that received spots made with both 20 mW and 1 mW
To compare spots over different distances, I use the 
Calculated electrical field strength, E, in microVolt per meter.
For details see the WSPR Propagation Analysis page of this Blog.

The lower the electrical field strength the better the propagation.

A power ratio of 10 means 10 dB
Please notice the the value for E is given in Volt/m, so a Voltage ratio of 10 means 20 dB
Which is indicated at the top of the table.
A Voltage ratio of 10 is a ratio of 100 in power.

The table shows stations that received the signals, that were transmitted with 1 mW and 20 mW.
Notice the difference in field strength in spots made with 1 mW or 20 mW.
The difference in field strength between the spots of 1 mW and 20 mW is about two steps in this table.
This is about 10 dB.
This is no surprise because, the difference in power between 1 mW and 20 mW 
is  10 log (20 / 1) = 13 dB.

The differences in propagation are huge
The field strength of the spots made with 20 mW, received by ON7KO over 600 km, 
show a value of 0,3 microV/m to 0,03 microVolt/m. 
The ratio in voltage is 10 and the ratio in power is 100, which is 20 dB. Wow


maandag 5 mei 2014

SP DX contest

Poland - Voivodeships
My objectives
As a milliwatt enthusiast I tried:
* to make as many QSO's with the
   lowest possible power
* to make as many 1000 Miles per Watt QSO's as
   possible
* to work as many different prefixes as possible for the
   BQC- Marathon.

1000 MPW
The distance to many of Voivodeships is more than
500 miles  from my QTH in JO22na.
Only the distance to the Voivodeships Z, B, D and
a part of W, is less than 500 miles.
With a power of 500 mW, and a distance of more than 500 miles,
these QSO's will be, more than 1000 Miles per Watt QSO's.

Crippled antenna
This year I did not expect much of my Inverted Vee.
Last year the top broke and I fixed the antenna temporarily.
The top is now just 2 meters above the roof.
And recently I found out, that the 300 ohm ribbon is damaged, so only one wire is still connected
But the antenna worked better than I expected.
Click here to read about the state of the antenna.

1000 Miles per Watt
The number in red, show the QSO's with more than 1000 Miles per Watt.


zaterdag 3 mei 2014

LZ69VZ

General Vladimir Zaimov
I just started in the ARI DX contest.
This is an interesting contest for a low power enthusiast like me,
because this is a DX contest, so I can work any station, so many stations can be worked with low power.
For the first QSO, I selected the very strong signal of OM5WW and worked him with just 50 mW.

The second station was LZ69VZ.
I like stations with special calls, so I gave him a call.
After exchanging the numbers, something very remarkable happened.
I got a question. At first I though that I had to repeat my call.
And repeated my call. But the question was . . . .
PWR?
So the question was: what power do you use?
I immediately thought, this must an operator, that had met me many time before and knows from my QSL cards that I often use low power. And indeed, the operator is Gosho LZ1ZF, who I meet in many contests.
I gave: 500 mW. hi

Thank you Gosho. My 1000 Miles per Watt QSL for LZ69VZ will be on his way in a few weeks.
If you hear Gosho, give him a call.