I’m happy that most of the work is done and this little transceiver is putting out its 5 watts. The signal looks quite fine on the oscilloscope. Me happy 
If you like to look into the schematics, most of them are available (with german text) here:
http://www.peter-rachow.de/k4_1.htm
http://www.peter-rachow.de/k4_2.htm
http://www.peter-rachow.de/k4_3.htm
http://www.peter-rachow.de/k4_4.htm
http://www.peter-rachow.de/k4_5.htm
As you can see from the 4 new pictures, the next step is done. The transmitter is ready and working. One more to go: The “linear amplifier”. Up to now it is about 200mW that is coming out. Finally it should be around 5-6 watts.
Here you see my “work place” for home-brewing and some early stages of the SSB transceiver project.
- Hartley VFO -> Working, little drift
- SSB-Modulator + BFO -> Working (Tested using an oscillocope and some test-tones)
- RX-Stage (from antenna to IF-amplifier) -> not optimal yet
Recently I completed my RF home-brewing equipment buying an old dip-meter. Got that one for 50 EUR: Leader (Japan) – LDM-810, here are some pictures.
http://elektronikbasteln.pl7.de/historische-filme-zur-nachrichtentechnik.html
From there e.g.:
(German docu about the ham radio topic in general)
(“Judica brothers” – Part 1 of 4)
Some other non-video link: http://elektronikbasteln.pl7.de/links.html
Need to check out an old CSR?
openssl req -in <filename> -noout -text
shows you the details.
And in order to produce a new CSR you could use:
openssl req -new -nodes -keyout dateiname.key -out dateiname.csr -newkey rsa:2048
I just had a steep learning curve when starting to build the 20m SSB transceiver mentioned in the book recommendation some posts before this. There were some simple bipolar transistor amplifier stages where I had some curves on my oscilloscope that were far away from sinusoidal. Instead of soldering some resistors in- and out a couple of times I tried to virtually pre-test it, using SPICE. Worked out great!
Try this: http://www.linear.com/designtools/software/#LTspice
For all of you looking for a great thinclient OS based on linux, try this: http://thinstation.org/
A couple of weeks ago the new major release was done. I already implemented this for a customer and it works great.
If you have any troubled I recommend the nabble mailing list of the project:
http://old.nabble.com/Thinstation-f4216.html
(This post in in german because the referenced book is as well.)
Wer sich mit dem Selbstbau von Amateurfunk-Transceivern, den theoretischen Grundlagen und verschiedensten Selbstbauprojekten (klein wie groß) beschäftigen möchte, dem sei dieses Buch wärmstens empfohlen.
http://www.peter-rachow.de/qrp_buch.htm
ISBN-10: 3881803270
ISBN-13: 978-3881803274
Ich werde mich demnächst an den Aufbau des dort beschriebenen “Abschlußprojektes”, den 20m-SSB-Transceiver machen.
Erste Erfahrungen und Erfolge habe ich mit diesem SSB-QRP-Projekt gesammelt:
http://www.phonestack.com/farhan/
Er ist konzeptionell mehr auf low-cost und allgemeinverfügbare “0815-Bauteile” aus.
I just learned that this is the correct practice of “always_bcc” in postfix:
Either your configure (main.cf)
always_bcc=my-archive@somedomain.de
-OR-
you set
sender_bcc_maps = hash:/etc/postfix/archive-check
recipient_bcc_maps = hash:/etc/postfix/archive-check
if you want it selectively choose certain addresses or domains to BCC somewhere.
Where the content of /etc/postfix/archive-check could be:
@my-nice-domain.de my-archive@somedomain.de
Meaning that all the mails FROM and TO the my-nice-domain.de will be BCC’d to my-archive@somedomain.de