That 58mm diameter toroid will have a core cross section in the region of perhaps 300mm^2 (about 17mm square). 2000V DC supply if it is being used as a transformer, means something like 1400V RMS m
Yes, but that's all an engineering problem. I'm sure the wire probably exists. I've never played with a valve since dabbling in old TVs of the 1970's era, and never high power stuff. However, I hav
You can just about get away with clocking the DDS directly for 137kHz. With and additional divide by 16, your DDS has to produce 2.2MHz which is within the capability of a DDS running at 10MHz clo
humiliation of being a significant part of a mHz off QRG, ;-) The upside is that such offsets are perfectly deterministic. Knowing your clocking scheme, and assuming that your controller always
AH HA ......... I see the significance of your question. 176 = 4 * 44 :-) That factor 4.44 (or 4,44) is actually SQRT(2) * PI 'jnt On 15 November 2015 at 09:18, Clemens Paul <[email protected]> w
Mainly as a system test, I'm radiating an EbNaut signal. Details are Frequency 137780.000 +/- 1mHz (DOCXO only for this test) Coding 8K19A Symbol period 0.5s (2 symbols / sec) Message length is
Its still going. At 1611z I ran rsNTP and it made a PC clock adjustment of 0.4 seconds, which with the 0.5s symbols used for this transmission will glitch slightly . Pleased to note that a local reco
Good signal from you Andy despite most of my antenna being on the ground! Is there a beginners's guide to receiving? I looked at the ebNaut Windows software page and it says: "Spectrum Lab will fi
I have set up a dedicated small SpecLab instance for EbNaut data, with spectrogram uploads to https://dl.dropboxusercontent.com/u/26404526/EbNaut_spectrogram.png . The signal is generally weake
Hi Andy, below are bit-error derived Eb/N0 results of your decodes here. The gap between 17:20 and 20:10 was me taking a break, and 21:20 to 22:20 washed out by local QRM. I'll call it a day now
Details of my Coherent LF receiver for digitising a signal centred on 1kHz then sending I/Q baseband samples over a serial link to a PC can be found at http://www.g4jnt.com/Coherent_LF_Receiver.pdf T
Without a doubt, One from FTDI chip : www.ftdichip.com Absolutely flawless, drivers easy to install. Never had a single problem with their family. I use the raw FT232 chips and ready made modules ,
Alan - You're forgetting the loading coil has to be switched out when using the loop at HF, so the relay has to withstand the full RF voltage when using it as a vertical at LF/MF. So you'll need
Hi Andy Surely the voltage will not appear across the contacts, though I agree contacts to activating coil might be a problem. Yes reeds area problem because I think of the reed material. I only u
The Vacuum relays that used to be plentiful at rallies may be good enough. They were designed for high power auto ATUs and cpuld certainly withstand many kV. The currents in such ATUs, at teh kW
Nothing here either - I've been recording each 17.4 minute session using sampling rates of 31.25 or 62.5Hz, but the decoder throws up either nothing or a garbage decode with 30% bit errors indicated
