Saturday, 11 June 2016

47 Amps Power Supply

Henny, PA3HK, had some used Hewlett Packard Power Supplies for sale. Yesterday I picked up one. It is a rather small unit (27 x 6 x 6 cm) and is capable of delivering 47 Amps (!) at 12 Vdc.
I made the small modifications to get it to work (3 jumpers installed and a 27 ohms resistor in the power supply of the fan) and now the unit runs fine.

I intend to use it for the 145 MHz transverter discussed earlier.


Tuesday, 17 May 2016

First 2m SSB QSO

First 2m SSB QSO realized with homemade transverter (See my blogspot article April 23)
Henk, PE0HZD replied on my request to make an USB QSO on  144.550 MHz.
Allthough our station distance (Zoetermeer Buytenwegh .. Oosterheem) is about 5 km´s it is worth to mention it..



Sunday, 24 April 2016

Jupiter

Last Wednesday evening there was a micromoon in a clear sky. A good opportunity to make some photoos. I found Jupiter in the constellation Lion.


                                                        Constellation Lion


Jupiter is the large dot left from the middle, the star Regulus (a blue giant) is on the right

The picture was taken from the 'silence area' near Weipoort. With an exposure time of 8 seconds and the light from the micro moon the area was captured:



Some amateur astronomers make beautiful pictures from the planets. For example Richard Bosman: http://www.astrofotografie.nl/index.htm
He made this nice photoo from Jupiter:









Saturday, 23 April 2016

145 MHz transverter

I found an interesting article in Funk magazine from May 1999.
It describes a 28 MHz to 145 MHz transverter.
Since I would like to use SSB modulation on 2 meter I am considering to make a transverter based on the schematic shown here:


My Yaesu FT450 can be used for the 28 MHz Intermediate Frequency processing.
Then all modulations (AM, FM, SSB, CW, digimodes) will come available.

I still have a power module M57719 (145 - 175 MHz) from Mitsubishi waiting to be used; this module can be used to boost the RF power of the transverter to a level of 14 Watts although I am not sure whether the power module can handle AM and SSB signals.


Wednesday, 20 April 2016

eQSL from Albania

This week I received my first eQSL from Albania from a digimode QSO I had Augustus 2006 with Dimitri. The callsign of Dimitri is ZA/IW2JOP.

                                  eQSL from ZA/IW2JOP
                                                      Albanian scenery

Saturday, 19 March 2016

Betelgeuse

Betelgeuse is the ninth-brightest star in the night sky and second-brightest in the constellation Orion. The distance to us is estimated at 640 lightyears. 

It is a first magnitude star and with the bare eye you can see it is reddish. The star's name is derived from the Arabic Ibt al-Jauza, meaning "the hand of Orion". 

I managed to make a photo of Betelgeuse ("Betelgeuze" in Dutch) early this month with my Canon1000D. An exposure time of 12 seconds was good enough to capture the red supergiant (30 times the mass of the sun).





It is funny to realize that the light that Betelgeuse emitted in the year 1376 arrived in 2016 on earth. In 1376, Yusuf III, Sultan of Granada was born.





January 2013 I made this photo of Orion. Brightest star Rigel is found in the right hand lower corner.

Saturday, 16 January 2016

eQSLs from Toscane and Andorra

IK5ZUL, Giancarlo, confirmed our 4m QSO  made July 2012:


Another remarkable QSO confirmation was sent by Archie, C31BO. It concerns an old QSO from July 2006. The QTH, Andorra, makes this card valuable to me.



Saturday, 2 January 2016

JT beaconing on HF


JT65 is an excellent mode for QRP experiments on HF. This weekend I did some short trials with this mode on 5.35 MHz with my "MARS"-modified FT450.
My 5 Watt JT65 beacon signals were captured by the PSK reporter website:
https://pskreporter.info/pskmap.html

I was inspired by Bas, PE4BAS to activate the beaconing mode in JT65 instead of WSPR:
 http://pe4bas.blogspot.nl/2015/12/beaconing-with-jt-modes.html
                                      First JT65 beaconing attempt January 2, 2016





                                      WSJT-X screen during beaconing

And.. heard by DP1POL, Antartica, distance 13.687 km with 5 Watts on 14 MHz:




Results of JT9 beaconing (14.078 MHz) during 1 hour on 20 m, January 3-2016,  were not too bad:



Sunday, 1 November 2015

MARS mod for FT-450

There is a way of extending the TX frequency range of the FT-450 transceiver. The so called “MARS” (“Military Affiliate Radio System”) modification provides out-of-the band operation of the transceiver. You can operate anywhere within the range 1.8-40 MHz after the transceiver has been modified.

The modification is simple. Just remove jumper JP4002 on the control pcb and make some settings. A description of the mod can be found here:
http://www.santerweb.net/wp-content/uploads/2013/01/MARS-Mod-for-FT-450.pdf

YouTube shows the instructions as well. For example this one for the FT-450D:
https://www.youtube.com/watch?v=u8kqyekwPxc

Example of out-of-band operation:


Jumper to be removed:

It took me some courage to open the transceiver and do the mod, but in fact it turned out to be rather simple.





Sunday, 18 October 2015

KT-8900 VHF/UHF transceiver

If you are looking for a small, low budget, VHF/UHF transceiver the KT-8900 from manufacturer QYT from China might be your choice.
For under $100 you are the owner of this FM mobile transceiver with a weight of only 400 grams.
It has a frequency range for VHF from 136 to 174MHz and for UHF from 400 to 480MHz.
Transmitter output power is 25W in the VHF range and 20W for UHF operation.

http://www.ebay.com/itm/QYT-KT-8900-Mobile-Radio-Double-Transceiver-For-Car-VHF-UHF-136-174-400-480MHz-/252081794687?hash=item3ab13eee7f:g:d4kAAOSwHnFV6vEk