Wednesday, July 29, 2009

short update on the WSPR/QRSS trx

This project has been resting for a a while. Yesterday, some progress was made. The local oscillator now has got a buffer/amplifier producing much more power than the mixing stage would ever need. This stage uses a 2N2222A in an emitter follower like configuration.

Even though the signal is pretty clean, in order to sure, I added a crystal as filter. Output level is adjustable to the needs of the mixer by a trimmer.

Here's a photograph of what there is sofar.

Presently I assume that I would need something like 2V peak to peak to properly drive the Polyakov-mixer, thus the buffer will be run with stabilized 5V.
Oscilloscope shows 1V/div, no further surprise here...

Let's see how far I come today....