That problem can be solved by using a return line and booster transformers that minimises current leakage into surrounding earth: https://library.e.abb.com/public/f1200714de5086c585257d7300287357/1LF
I 've had good experience with box kites. I used to play with the classic version many years ago. The lift is impressive already at moderate wind and may even become dangerous at strong winds (not jo
Hi Stefan I thought about your 9kHz PA efforts when I found this class D PWM chip capable of ~300W up to 100kHz with very low distorsion. Amazing performance from such a small $6 SMD chip! http://ww
Even more linear QRO for dreamer's band: http://www.ti.com/lit/ds/symlink/tas5630b.pdf Den 2016-04-26 kl. 17:18, skrev Johan Bodin: Hi Stefan I thought about your 9kHz PA efforts when I found this
Hi Stefan, Expensive? No! $6 in big quantities and they offer samples for free. Check ti.com. /Johan DK7FC wrote: I would assume such a chip is quite expensive and not easy to get in small amounts(?)
Hello Roelof, your 17dB agrees very well with my measurement made many years ago, I also found the "backwave" to be 17 dB below key-down power. Assuming the key-down output is 200kW, "only" 4000 watt
Thanks Paul, your article is the best introduction to FEC coding that I have ever seen! It quickly gives an intuitive feeling for how and why it works. 73 de Johan SM6LKM Den 2016-12-26 kl. 19:16, sk
Or this, 72m tall, 27.5m diameter: http://a-ripellino.se/z/wp-content/uploads/2014/01/a-ripellino_ackumulatortank_vy01.jpg 73 de Johan SM6LKM 73, Stefan
Hi Joe, I have almost forgotten that old LF converter. I just rediscovered the web page in an Internet museum! :-) http://home4.swipnet.se/~w-41522/lfconv/lfconv.html Regarding T1, inductance depends
John is right. The transductors at SAQ can be seen in this photo in google street view: https://www.google.se/maps/@57.1139306,12.4045874,3a,75y,221.02h,87.43t/data=!3m7!1e1!3m5!1sA9thq95lEHf5u-4IrG4
Thanks Stefan, yes, the Pungs-Drossel is an early transductor! I just love the sentence: "Das Mikrofon musste sich unmittelbar am Sender befinden und der Sprecher war ständig in Gefahr, sich an den v
Hi Stefan, you can find//simplified schematic diagrams of the SAQ TX here, including the "magnetic amplifier": http://retroradio47.blogspot.se/ http://www.nsarc.ca/hf/saq.pdf 73 de Johan SM6LKM
I measured SAQ's backwave as 17dB below key-down power, "only" 4kW leaks out when the key is up. You are on the right track. Just need another 12.5dB to reach SAQ performance! ;-) 73 Johan
Haha! :-D The impressive work of some talented radio amateurs seem to have shifted our view of the RF spectrum; 137kHz is now "microwaves" :-) 73 Johan SM6LKM Den 2017-06-01 kl. 21:49, skrev Markus V
"Armchair copy" at ~280 deg, that's really impressive! Congratulations! 73 Johan SM6LKM Den 2017-12-03 kl. 13:04, skrev Paul Nicholson: Have a look at http://abelian.org/vlf/fbins2.shtml and swing
DK7FC wrote: ... it was the mistake of the secretary. It is already the second edition. In the first one she wrote MHz :-) I hope that you kept that paper as it entitles you to a private 20kHz slice
Congratulations Markus! /Johan SM6LKM Den 2018-01-27 kl. 16:18, skrev Domenico IZ7SLZ: Hello Group! i have found an interview of Markus in the Siemens's website: https://www.siemens.com/global/en/hom
I thought some here might be interested in this thread I spotted this morning on the EEVBlog forum: http://www.eevblog.com/forum/rf-microwave/lf-tube-radio-restoration/ The restoration of a huge Tele
Or, if you prefer C, http://www.smorgasbordet.com/pellesc/ 73 Johan SM6LKM Andy Talbot wrote: All in PowerBasic, command line compiler version (By far the nicest way to programme simple things that d
Hi, SAQ is about to start up 9:30UTC and send a message at 10:00UTC. http://alexander.n.se/saq-on-air-on-may-1st/?lang=en Live video stream here (I think): https://www.youtube.com/channel/UC-
