By USB, do you mean the frequency specified is the carrier and the centre 800 Hz (or whatever) higher, or is 7000.003 the centre of the transmission ? I'm assuming for now you mean the latter, so off
I will be transmitting another Jason test transmission at low power tonight 137.500000 kHz < 500uW ERP. Start time at least by 1900z, and probably earlier. Andy G4JNT
That would be very helpful. Now I've added the code to programme the Jason increment into EEprom via the 'normal' DDS control, (done this morning after sending the last EMail) there are only 60 words
I'll put out a JASON test transmission tonight on 137.500000, at 1900 UTC (2000 local) using the low power Tx. I may be on sporadically earlier than that, using the high power Tx to test for any EMC
I seem to have successfully added a Jason mode to the AD9850/51 DDS Module. It certainly works from compur to computer anyway ! The DDS module is put into Jaso mode by grounding PB2. Then it receives
Well, I think that solves the problem. Makes sense, and Droitwich is certainly a 'very high power transmitter'. But a lot has been mentioned over the last few days about the technology of high power
This filter is shown in the LF Experimenters Handbook on page 25, as part of the outline design for a narrow bandwidth LF receiver. The frequency response I measured is given on page 26 If you view t
Its was I ........... 1) Take a handful of watch crystals, from the same batch (buy 10 or 20 from Farnel / Maplin ??) 2) Connect 5 in series to form the top elements of a ladder filter; you now have
I vaguely remember a mention in RadCom of long ago. Seem to recall it operated in the 3MHz region, SSB, with a antenna woven into clothing. Andy G4JNT This was a body-worn radio system intended for f
Yes please, I would like the PIC code. I did something similar in the past using a 16C71 PIC with 8 bit A/D. This sampled at 4kHz and formed I/Q samples at 1kHz output rate as follows for every 4 inp
If anyone does design a USB interface for a medium to high speed A/D they could do well marketing it commercially. And then go on to look at other USB driven test equipment modules. As far as I can s
My works account comes through a firewall on another site, then over a more secure network to the desk, so has the advantage of being always on and having all working files to hand for sending or dow
Does the 4CX250 know that ? The screens in those can be blown as quickly as any transistor if you get an anode to screen arc-over. I've seen 24 '250 valves in a big ship transmitter blown in a single
I don't know about the IC756, but the IC746 derives all frequencies from one master oscillator at 30MHz. The high stability option for this is an ovenned crystal, and takes several minutes to get to
There is an awful lot of controversy over the G3LHZ theories on loops...................... Andy G4JNT Dear Dave, Rik, LF Group, At 06:36 28/11/2002 +0000, you wrote: I have just done a couple of cal
I didn't get anything like that, but the negative voltage generator has a pronounced threshold as the device starts to avalanche. I wonder if you are getting an effect caused by the capacitive loadin
No, where is his article ? I remember Bob Pease and many of his practical engineering tips made fascinating reading, but don't read EDN now. Is he a Ham, or just an analogue person ? This one is a wi
Has anyone complained ? The first one certainly created enough interest, even led to a few ideas for loop resonating. You need an ordinary NPN transistor (eg. 2N2222), a 9V battery, a 1k resistor and
Right, done it. Now that's very interesting !!!!!! Exactly as you specified, even down to the same 2N2222 device. The B-E junction breaks down at 7.56V, ie. Vbe = (minus) -7.56V With a DVM, 10M input
