Hi All - Its no good at this stage looking for small signals. All I'm trying to do is prove the HARDWARE. At the moment I have a QSD type receiver delivering a signal centred on 1kHz. This is b
Hi Andy I havent checked recently but as far as I know NPL measure Droitwich twice a day and post the tabulated results on their web site.If they see a problem they contact the contractor (was Merli
Hi Andy I havent checked recently but as far as I know NPL measure Droitwich twice a day and post the tabulated results on their web site.If they see a problem they contact the contractor (was Merli
Hi Andy, maybe or maybe not. I did detect a "breathing effect" of a few parts in 10^11 soon after the synth was replaced at Droitwich. At this level I was not sure of my own stadard's stability whic
3C90 is a type of ferrite material, and doesn't specify a transformer type. What is the Ae (cross sectional area) of that core? Or just the diameter to work it out from? Andy On 2 November 2015 at 13
Ae is specified as 211mm^2 for that size core, So, at 137kHz Mike's 16 turns with a Bmax of 0.1Tesla means : V = 4.44.F.N.A.B = 205 Vrms In a 50 ohm system this equates to 840 Watts Andy G4JNT On
That is not the core diameter - if it were it would be an ENORMOUS core. Chris responded in a PM with the core type it is ETD49 which has Ae = 211mm^2 Using Mike's 16 turns, and Bmax = 0.1T, that al
Ae = 152mm^2 So a bit smaller than Chris's ETD49 core. Andy On 2 November 2015 at 16:22, Mike Dennison <[email protected]> wrote: The ID is 40mm. It is similar to the one at: http://uk.f
A pretty thoroughly top loaded vertical, Heff = Hactual 'jnt On 4 November 2015 at 19:50, Graham <[email protected]> wrote: (about 16 fee thigh, strapped together at the base only) I wonder wh
I dont think its that simple Andy , 16 ft is not much for 136 , and the loop runs up from the feed point , which I think is a corner ,, so at what point is it a radiating ele
Although my query is specifically with the authors of EbNaut and Speclab. posting via the two LF groups so everyone can join in: I now have a completely locked narrowband digital receiver that delive
Hello Andy, The wave files written by Spectrum Lab are indeed decimate I/Q pairs (camouflaged as a stereo wave file). Since the sampling rate (etc) in the header don't allow the required precision
I've been using the MSF 60khz signal as a test source for cohernet LF Rx development. And in doign so I've noticed a couple of oddities First was tonight, see http://www.g4jnt.com/DownLoad/MSF_Log2
Feasible yes, but I wouldn't recommend it. I advise recording the signal first, then present the recording to the decoder. This, so you can repeatedly run the decoder with different frequency and
The recent resurgence of interest in BPSK on the LF bands reawakened my unease at using this hard switched mode with high power transmitters. I recall ages ago using Coherent (10 B/s BPSK) and heari
I'll say it again V = 4.44.F.N.A.B (all SI units) THAT is how you size ferrite cores. It tells you more or less everything you need to know to make ferrite transformers. Keep B to less than 0.1 at
Try the Anlaog Devices web site - www.analog.com I built my own PCB, http://www.g4jnt.com/AD9852module.pdf (PCBs are no longer available for that, though). That particular DDS is a bit out of
