So far all decoded successfully in Nuremberg. The signal is strong but propagation is really playing havoc on your phase (see the peak shape in the attached plot from 19:20). start car. sym. UT dB dB
Hi Paul, Your core is a good choice and it will handle 500W without a problem on MF. I'm also using the blue EPCOS cores for nearly any transformer on LF and MF. https://dl.dropboxusercontent.com/u/1
Thanks Markus. I see what you mean, the phase is a mess. I hope that's propagation and not my transmitter! EbSynth is good but I'm not convinced yet that the multiplier is behaving. We've still got t
Thanks. I don't think my signal is making it that far tonight. I'll close down at 22:30 so the last complete EbNaut will begin 22:20. Maybe a few more tweaks and another go tomorrow night. The varia
The attached picture shows an autotransformer wound on a a 58mm (58/41/18mm) Philips (now Ferroxcube) core made of 3C85 ferrite. The transformer was used by SM6PXJ and me at 7S6SAJ in 2000 to bring t
Starting from cold, if I do a short run at full power, the wires get hot but the core only gets slightly warm. I conclude the heat is coming from the wire not the core. Yes I'm getting keen on flat w
Lasted until 17:21. Only one complete EbNaut, 17:00:00 to 17:08:32 The FETs are getting a lot hotter and so is the transformer, even though the DC input current is about the same. Primary current sh
Running again, hopefully for a bit longer this time. Freq: 477690.00000 Hz Start: 22:40:00 UT Coding: 8K19A Symbols: 512 at 1 second Chars: 5 Repeat: XX:00 XX:15 XX:30 XX:45 After a cup of tea I had
Attached a circuit of part of the push-pull PA. The center tap of the primary is at AC ground with the DC supply coming in via a choke. I've been getting a lot of ringing on the drains, as is fairly
Will close down at 01:00 with the last EbNaut at 00:40 and tomorrow I'll try to figure out how this circuit is working. PS. Am getting 3 copies of Markus' emails to the list. Looking at the headers,
Ah interesting , well everthing is wierd at AOL there days including the CEO ! Alan G3NYK Will close down at 01:00 with the last EbNaut at 00:40 and tomorrow I'll try to figure out how this circuit i
Hi Paul, Will you run some EbNaut tests on LF some day? I think you will need less power, maybe you can use the same PA with the same core and same windings. LF has much less QSB and we could do dayt
Anyway noticable that you quickly expected the problem must be on the blacksheep side. You somehow just seem not to like it, just because it is 'old'?!? 73 :-) Am 29.02.2016 01:56, schrieb Alan Melia
Stefan You are implying emotions that are not true there Stefan, I am frustrated with it because there is no way to investigate problems or do admin. I do keep reminding that we have have no control
Yes! I'm having fun with transmitting. I'm nearly done with MF and am looking forward to rewiring the multiplier for LF. The PA is supposed to be broadband so perhaps it will work at LF without chang
Signal on air from 19:18 Freq: 477690.00000 Hz Coding: 8K19A Symbols: 512 at 1 second Chars: 5 Repeat: XX:00 XX:15 XX:30 XX:45 First complete EbNaut started 19:30 -- Paul Nicholson --
Hi Paul, I would recommend feeding DC not via the center tap of the output transformer because the DC current is biasing the core which reduces its "dynamic range" and increases losses and heat. Inst
I understand. I've seen that arrangement in circuits of HF PAs and wondered why it was done that way. It would simplify the primary winding too. Thanks for the tip, I will certainly do that, I've got
