From G3YMC but the situation as I understand it. It is rather interesting to note that many of the early operators on 136 were ex top band operators. It seems most of these have now returned there. I
I will keep with the 5 watt transmission this evening, but may go to high power on Saturday afternoon or evening. Frequency in all cases will be 137790.00 I guess QTR means frequency, have never seen
It will be going again this evening, hopefully starting quite early. The message will be a bit longer this time and I will also close up the tone spacing a bit. 0.5Hz spacing, when used with Argo on
Software to generate two tone visual signalling is written and just needs final testing, then I should be able to put out some test transmissions within a day or so for evaluation of the technique. A
But for every annoyance Gates and Co. introduce to operating systems, some other hardware manufacturer comes along with a new device to help. A new PIC device, the 16F628, has come along as a replace
It's code is as good as anything, at least to start with ! I've started writing the software to drive the DDS based transmitter for this mode, just a straightforward case of adapting my SMT Hell code
The parallel port would enable simple hardware to allow a crude D/A converter for driving a VCXO, but isn't the LPT port difficult to drive under Windoze programming ? The COM port is much easier and
Given the choice of three cascaded doublers with all the intermediate filtering needed, using devices based on a circuit topology even older than the CD4046 (the diode ring or Gilbert cell multiplier
According to the RSGB News, there is a Royal Navy Spark Transmission from Poldhu today, to celebrate the marconi centenary. Does anyone have any further details, such as a frequency ? Very approximat
Actually I WAS transmitting a SMT Hell signal, approx 10Hz above this transmission on Friday night. Signal bandwidth was 2Hz with 2s pixel intervals, but the power was only -3dBm as that is all I cou
That just about sums it up. A short fat monopole will give the sort of performance of a ....well... a short fat monopole ! Better than a short thin one, but still not very good. I am always unconvinc
Looking at frequency standards for LF, the requirements are slightly different than for the higher frequencies. For microwaves, where instantaneous frequency (over a few seconds) needs to be very goo
Varying the drive duty cycle to change the RF level does not give the result expected at first sight. While the DC level does vary proportional to the duty cycle, the RF carrier, which is revealed vi
BTW, does anyone know how to compare the weak signal performance of Jason and QRSS or DFCW? It seems clear that the increased bandwidth must result in some loss of SNR, but there will also be gains b
NO NO NO ! I don't wear glasses, but tried these for IC work. They were great for magnifying, but the convergence was wrong and as soon as I took them off I was cross eyed and could barely see for so
The AD9850 wants a (nominal) 0 - 5V squarewave waveform, the duty cycle is not important. You haven't specified the absolute voltage levels in your diagram below, but if it is nominally a TTL type of
Are you aware of any possibility to buy online a PCB ready made for the AD9854 ? It would suffice a layout that brings all the pins to more manageable pads where to connect the rest of the circuit. I
Now I've fallen into the trap and done it myself !!!!!!!!!!!!!!!!!!!!!!! We need to check the subject line of messages when posting to this reflector. There have been a whole string of interesting po
Problem is, I am horrified at the very thought of having to produce a PCB for it, let alone soldering it.... SMD make life difficult for the hobbyists, I am afraid.....:-( Alberto I2PHD Take the plun
The first URL seems to require getting a Yahoo ID and entering a lot of information I'm not preparred to give - is this necessary ? The second URL seems a lot easier - just asking for an EMail addres
