Hello Martin, I've just chnaged my RX' qrg from MW to LW,here it comes. 2016-10-12 13:06 2E0ILY 0.137551 -28 0 IO82qv 0.01 DL4RAJ JN68kj 1199 108 Let's see if I can spot Andy's next transmisssion. 73
Hi all, probably first DL-> JA in WSPR on MW 2016-10-13 20:22 DJ0ABR 0.475665 -25 0 JN68nt 0.2 JA3TVF PM74pc 9166 45 See also http://njdtechnologies.net/101416/ 73 Clemens DL4RAJ
But,according to Stefan there have been several (false) fire *alarms* with the fire brigade going into action caused by his QRO transmissions on LW! 73 Clemens DL4RAJ
Hello Andy, *If* there is a DSP pre-filtering in the SW and the noise measured in this BW is scaled up to 2.5kHz which includes the appropriate correction then a hardware filter (or digital filter in
Hi Toru, from my own experience I have to confirm that DJ0ABR is very rarely looking into his emails.It seems also impossible to contact him via phone (answering machine but no back call). I shall tr
Hi Toru, did you get a response from DJ0ABR? I have emailed DH5RAE to inform DJ0ABR about five days ago but did not receive any answer from him either. 73 Clemens DL4RAJ
Hi Steve, if you prefer a reliable and accurate inline meter there is a ready to use solution but you have to spend some money. It's the digital vector wattmeter LP100A. http://www.telepostinc.com/ Y
Hi Gary, on DL4YHF's HP you'll find some info about the IC706 (first version,i.e. no MK1 nor Mk2) on 630m. http://www.qsl.net/dl4yhf/mf/mf.html#IC706_on_MF It would appear that all three versions of
Another way - a bit more complicated - to reduce heating significantly is to feed DC not via the center tap of the output XFM but via separate DC chokes. This would eliminate the DC bias of the core(
Here is a picture of a professional made Class D 500W MW PA by ID Elektronik. http://www.id-elektronik.de/produkte/mittel/mittel.htm It uses also DC feeding by a separate choke, not via the output t
Hi Chris, I've found additional info on the broadband Wilkinson combiner on my hard disk, which I believe stems from an old ANZAC data book. The info refers to T2 and there are two ways of how it can
... Any change of the load impedance (R,X) on the secondary side is seen by the PA on the primary side proportionally to the step up ratio. Perhaps because it is not so easy to get hold of those ori
Hi Luis, At this low QRG skin depth may become an issue. The coax shield might be not thick enough. So it's probably worth a try with twisted pair. 73 Clemens DL4RAJ
Hi Luis & Stefan, Hum means H-fields. Coax shield is completely transparent i.e. without any effect to H-fields. The question is where the hum is being picked up. 73 Clemens DL4RAJ LF_Soundcard_32KHz
Hi Chris, I have a tool by DJ5IL here which predicts around 60°C for the cores (excluding heat caused by the winding) and ca. 480 Gauss flux density. 73 Clemens DL4RAJ Attachment: 3xFT240-77_137kHZ.J
Hi Marco & Chris apologies for the delayed reply. There was indeed a typo. It should heave read 12.5Ohm because the amp is designed to work into a 50:4=12.5 Ohm load. Then there was another wrong ent
Hi Stefan, Chris has provided this link several times http://www.w1vd.com/LPF.pdf You can contemplate this filter as two 3-pole T-type low pass filters in series. Then every element has 50 Ohm reacta
