Contents :

A collection of thoughts, and my notes about experiments and ideas, technical or otherwise, connected to Amateur Radio, Satellite working and monitoring and other electronics.

Sunday, August 29, 2010

Simple 80m Grabber Receiver Ready

Next time I will visit the OZ9QV grabber "Thor's Hammer" there will be another band active in grabbing : 80m

I have finished encasing a modified RockMite 80 (RX only)

Frequency drift is acceptable :
10 deg C : 3499.955
23 deg C : 3499.915

Yes - negative temp coefficient.

Since the temperature is expected to be within that range (most likely 15 - 25 for the majority of the time, and I expect to put the RX and PC into a cupboard, I would expect the local oscillator to stay within 3499.925 +/- 10 Hz for most of the time, quite acceptable.

The addition of another band to the grabber is worth it alone, I think.
New antenna needed as well.

I know that more activity is on 40m by now, but the winter should be good for 80m experiments.

The grabber is expected to run with an older, low powered PC, together with the 10 MHz grabber.

The new grabber receivers should be installed before the end of the year.

I am playing with an idea for a more stable grabber receiver for 3500/7000/14000 kHz, more on that later.
It will be a bit more complicated to build, so I will be taking my time.

Monday, August 23, 2010

Thor's Hammer again

Yet another alignment,

The receiver is drifting quite a bit, so the 'window' has been widened to 550 Hz, at least some signals are visible.

Further improvements to the grabber will happen later.