Thanks Wolf, I went to low power around 20:44 and turned off a few seconds before 20:50. The little spikes are from the EbNaut BPSK. Also I was winding the power up and down and measuring things so i
Maintaining a stable wrongness http://abelian.org/vlf/tmp/160226a.png Propagation delay here is around 0.52 mS. I'm missing 17mS of sleep each night because of this. -- Paul Nicholson --
Measures 0.075 fT here which is distinctly stronger than your usual signal, which recently has been around 0.05fT. http://abelian.org/vlf/tmp/160226b.gif Shows up well on the spectrogram http://abeli
I've done a lot of work over the years modelling air cored coils - and they're hard enough to get right. Throw in a core and it becomes a nightmare. So much depends on just how you wind and layer the
On again. Freq: 477690.00000 Hz Chars: 15 Symbols: 0.5 seconds Code: 8K19A Duration: 496 seconds, 00:08:16 Repeat: XX:00 XX:20 XX:40 I rewound the transformer, the primary windings are the braid of c
Been on now for 2 hours and all looks fine. I set up a fan and the toroid and FETs are nice and cool now. Is it normal practice to need a fan for the toroid? DC input is rock steady at 3.78 amps whic
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
I pulled the data out of the working directory of fbins from to flux b180 phdiff 2016-02-28_09:30 2016-02-28_10:30 0.08 99.2 114.9 2016-02-28_09:45 2016-02-28_10:45 0.08 109.9 134.3 2016-02-28_10:00
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,
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 --
No PPS so not much use for this application. You would definitely need a 1PPS output. Look for GPS based on one of the the LEA-6 chips such as http://www.amazon.de/dp/B017T0WP42/ I haven't tested th
Ah, well spotted. I see there are two left in stock, I am tempted to order one but Andy raises a good point regarding the desirability of a separate GPS antenna. The NEO-6 is a prospect then. The ot
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