My Dell Inspiron Laptop, when 11025Hz sampling rate is requested, actually gives 10800Hz (near enough) which was enough to completely kill JT4 decoding. (JT4 is a WSJT mode, not totally unlike WSPR
-- There is no 'chance' involved. The strong source coding employed in all the WSJT modes to get the number of bits to be encoded down to an absolute minimum, before proper error correction is added
And mine for the 503.8kHz beacon. Think they were used somewhere in the old Decca chain for fine tuning Andy www.g4jnt.com this email has been scanned for political correctness by the nanny state 200
VAC can cause timing problems inteh conversion of one sampling rate to another as it crosses the Virtual Audio backplane. I use cheap 'headphone dongles' to add additional soundcards for the SDR t
If you've studied the drain waveform when operating inrto a correct load, and assuming its all within design guidelines, then the trouble is because of nasty impedances presented by the antenna durin
And who do you think would bother if you did work one ? Who would even care ? Andy www.g4jnt.com this email has been scanned for political correctness by the nanny state 2009/11/13 M0FMT <m0fmt@yahoo
Does anyone know an Excel route so that when I copy and paste from the WSPR database, the date and time field can be separated. All the other fields copy uniquely into their own columns, but that m
I've been playing with ' CwGet ' http://www.dxsoft.com/micwget.htm . Its not very good at decoding these pulse-position-width mod ASK signals. There seemed to be millions of them QRMing the HF bands
My NoV specifically was not for manual CW. So, technically, my beacon is breaking the terms of the NoV by having an on-off 10 baud ident. Andy www.g4jnt.com this email has been scanned for political
This presentation was aimed at Microwave operators, but has plenty of relevance to LF http://g4jnt.com/MartleSham.htm Includes soundclips of CW buried in noise with accurately defined S/N ratios An
I queried a few instances on this some months ago, and several stations sugegsted the log was genuine. They're in the database, and can be found by searching with callsign and reporter filters set.
Not sure if it is significant, or just tuning, but the log of G7NKS reports of me are about 40 - 50Hz low in frequency, and varying by a few Hz from hit-to-hit over the last few hours. Andy www.g4jnt
I'm trying to get hold of a copy of this paper from 50 years ago. Does anyone have a scanned in version? The only web reference I managed to find pointed to a site ( http://tinyurl.com/d5bdo ) that
Crafty. 'should' be pretty foolproof. Any old soundcard without 48000Hz ought to just throw-up an error. Andy www.g4jnt.com This email has been scanned for damaging side-effects by the health and saf
Correction:- The IRF540 is also 100V rated, but a lot lower Rds on 0.05 ohms rather than 0.5 ohms for the IRF510. That may well contribute to overheating and damage on mismatch.
Thanks to all who responded, I do now have an E-copy. As Warren mentioned there are probably still copyright issues (after 50 years ??) so it can't really be placed openly on a web site... Andy
It has a calibration procedure built in, but as far as I can make out, is aimed at solving frequency offset / tuning errors. I may have missed something, but there seems to be no facility to calibrat
