Fernebo Bloggen

New Power meters

sm3sgp — Wed, 11 Apr 2012 18:42:52 +0000

The Easter holiday was spent in Luleå together with SM2WMV to construct the new power meters for openASC. The system is designed by Mike, and is using two AD8307 Log Amps together with an ATMega32A Microprocessor. The board will measure both forward and reflected power, do some calculations and send the data out on the openASC bus to be monitored at the operating positions. At SK3W we will use six power meters, one for each band. After the amplifier for each band, two directional couplers are connected to measure forward and reflected power. The directional couples are surplus, made for 2-3GHz, and the coupling is much lower on the HF bands. Since the coupling is different for each band and very low on 160m, we decided to calibrate each power meter individually.

Since we are running Multi transmitters, there is a risk that RF from other bands is entering into the couplers measuring Reflected power and indicating VSWR. The difference in coupling between 10 and 160m is about 30dB, meaning that the Reflected meter for 10m will be about 30dB more sensitive than on 160m. If a signal with 0,1 watt of power from the 10 meter transmitter is entering the 160m antenna, the reflected power on 160m will indicate 100 watt reflected power. This was solved by building small bandpass filters to put in front of the reflected port for each power meter. Mike WMV made a quick design in Elsie, and a couple of hours later they were built, tested and installed!

PCB’s from SJ2W

sm3sgp — Sun, 01 Apr 2012 07:26:25 +0000

SM2WMV Micke has made his antenna switch designs available to the rest of us. He is offering PCB’s to build your own antenna switch for a low price.

Have a look at the SJ2W Page

Russian DX Contest

sm3sgp — Mon, 19 Mar 2012 20:24:28 +0000

Call: SK3W
Operator(s): SM3SGP SM5PHU SM5TXT SM5AJV
Station: SK3W

Class: M/2 HP
Operating Time (hrs): 24

Summary:
 Band  CW Qs  Ph Qs  Countries  Oblasts
----------------------------------------
  160:   219     0       41        39
   80:   376   193       58        60
   40:   800   193       80        67
   20:   658   504       90        72
   15:   236    83       83        45
   10:    17     0       13         4
----------------------------------------
Total:  2306   973      365       287
Total Score = 13,240,164

Video from CQWW CW 2011

sm3sgp — Fri, 24 Feb 2012 22:45:15 +0000

http://www.youtube.com/watch?v=_T0BoAjCbzg

“>CQWW CW 2011

SM7LCB Pages

sm3sgp — Fri, 24 Feb 2012 18:07:52 +0000

Ulf SM0LCB has mirrored his web-pages at SK3W.se.

Have a look here!

ARRL CW Multi/Single

sm3sgp — Mon, 20 Feb 2012 19:54:37 +0000

Operating time  : 37h31

 BAND   QSO S/P DUP  POINTS   AVG
----------------------------------
 160     0   0   0       0  0.00
 80    87  30   4     258  2.97
 40   568  54  15    1701  2.99
 20   855  59  21    2565  3.00
 15   643  58  29    1920  2.99
 10    97  28   1     291  3.00
----------------------------------
TOTAL  2250 229  70    6735  2.99
==================================
 TOTAL SCORE : 1 542 315

Operators: SM3SGP, SM5AJV, SM5IMO, SM5EPO

This year we decided to go for the Swedish M/S record from 1999. Unfortunately the propagation was not enough and we lost the low band propagation totally the second night.

Weekend high lights:
SM5AJV served an excellent dinner on Saturday night.
Nice 15 meter run on Saturday afternoon.

40m yagi work

sm3sgp — Sun, 08 Jan 2012 19:23:01 +0000

The lower 40 meter yagi was tilted in the storm during Christmas. It is now back to operating position and ready for some pile-ups.

EPO on HF

sm3sgp — Fri, 06 Jan 2012 15:04:29 +0000

More antennas installed at SM5EPO. FB-33 Tribander for 10-15-20 meters up 25 meters above the ground. Also a 80m dipole was installed @ 22m.

Congratulations to PeO SM5EPO, that has now retired and now work full-time at the SM5EPO and SK3W Radio stations.

SM5EPO can be found here:
http://www.voacap.com/skimmer/?dx=sm5epo&band=

Electrical installations

sm3sgp — Tue, 03 Jan 2012 16:40:24 +0000

Started some work to improve the electrical installation.

EPO on 6 meter

sm3sgp — Fri, 30 Dec 2011 15:29:24 +0000

Some antenna work in the darkness. 50MHz antenna at SM5EPO, around 27 meters above the ground.