New antenna for 80 metres goes up

Surprisingly, the weather recently has been suitable for me to work on antennas. So even this late in the year I had an opportunity, not to be missed, to erect a new antenna for the 80m band; a base-loaded vertical wire element supported by a Spiderbeam heavy duty 12m long telescopic fibre-glass pole. The pictures show the antenna base with loading and matching coil inside the storage container, and the antenna's location.
I have just made my first contact on the 80m band using this antenna with a radio amateur in southern Spain, 2463kms away. My transmitter output power was only 35 watts. The antenna's performance could be worse !

Improved phasing exciter

I have completed some improvements to the single-sideband phasing exciter, ( post 25 January 2010 ), for my longwave transmitter, just in time for use during the good propagation conditions on the 2190m band over the winter.
The passive phase shift network was not producing accurate 0 and 90 degree phase shifted AF. In fact it was well outside specification; perhaps not surprising as I bought it in 1978. So I replaced it with an active circuit based on a dual op-amp. I optimised the unwanted ( lower ) sideband suppression at 800Hz. There is little point anyway in achieving exact quadrature audio channels over the entire speech band as the modes in use on longwave are extremely narrow-band.
I added a tuned class-A post-mixer transistor amplifier stage.
Upper sideband is now selected automatically as I have disabled the sideband switching facility; until such time when I see a lower sideband signal on the band.
The top picture is my signal, received on 137.7KHz, from just the exciter sitting on the workbench, ( lower pic ), when transmitting using chirped multi-tone Hellschreiber mode. As can be seen, the signal occupies only about 5Hz of band !

PC-to-PIC serial comms

I have been programming the EUSART module of a Microchip PIC18F4550 microcontroller on my MYDEV2 development board for RS-232 serial  communications with a pc running a terminal application; in my case 'HyperTerminal'. I have configured the connection for 1200 baud asynchronous operation. Although this is one of the slowest of the standard com port baud rates, however in conjunction with the 8MHz PIC clock it gives the lowest baud rate error of only 0.1%.

The connection is called PC-PIC_EUSART. Pressing any key 'wakes up' the EUSART and starts the sequence. The above capture of the Hyperterminal screen shows, for example, the steps taken to change the dfcw dot-dash frequency shift to 4Hz. All seems to be error-free !

Now that I have the connection working, I am considering incorporating serial comms functionality into my PIC controlled frequency synthesiser, so that values, e.g., relating to priority band and dfcw shift, which are held in PIC data eeprom, can be changed quickly in real time without having to modify, build and reload the entire source code file.