Thursday, 27 December 2018

First FT8 QSO!!!

I finally moved my operating position from the hall downstairs where I didn't receive any FT8 signals better than -15 or so. Now I am upstairs and signals are coming in 0 to -10. So I clicked on the huge signal coming in at 0 to -8, and low and behold he received me and I got my first FT8 QSO!

Here it is

Screenshot 2018 12 27 at 16 26 21

I am using the fixed frequency QRPver transceiver with their 6W PA amplifier into a WonderWand loop on the window sill, I have it in line with my home designed and made VSWR meter (see previous postings) and I get an SWR of 1:1.50. Anyway this is very encouraging.


When I received my transceiver from QRPver it was tuned to JT65 7076kHz, I delved inside and tuned it down to 7074kHz and it has settled about +50Hz high right now but quite functional. Nice little unit. Audio I/O is via a very cheap Amazon USB sound dongle to my MacBook.

The other thing I have done is to use a 40dB attenuator in the audio output line as otherwise it overloads the USB Dongle microphone input. The QRPver audio works at line levels, which is OK for the headphone output to the TX input, but too much for RX output to the microphone input.

Screenshot 2018 12 27 at 13 47 41

Screenshot 2018 12 27 at 16 28 03

Very pleased with myself.

Sunday, 16 December 2018

Aerial plans

For years I have been stuck with without aerial, I have a small loop and a pull up whip both tuned, but they are very inefficient... What's worse is that my house is old, and insulated on the outside - layer of aluminium and then polystyrene blocks! So I am living in a Faraday Cage. Seems stupid. but he facts are that where I living no outside aerials are permitted, and I do not have a way to run a cable from my loft to my operating position in the downstairs hall.

But now, we are going to re-arrange the house, which will mean an upstairs bedroom will be my new location, a simple drop down from the loft above. So a loft antenna it is.

First I need a balun as it will be a sort of tuned dipole as much as I can get into the space. The target frequency is the 40m band. So here it is

IMG 0813

A conventional design built in a small plastic box. Looks good. Two terminals and a PL259 connector.

The antenna was put up by my son in our attic. When I checked it out - using my trusty Si5351 SIGGEN and a resistor bridge feeding my trusty RF POWER METER. I found it was resonant at 8.3MHz, too high. So far I have not persuaded my son to come back and lengthen the two sides, by stretching out the spring thingy.