More DSP Experiences with Filters and DSP Radio's.

From 432 And Above EME Newsletter, Februari 1996:

HB9BBD, Dominique reports:

I had a very interesting QSO on 23 cm with VE1ZJ for initial #67(419/559) on Sked. The interesting point was the initial of course, but technically there was a big surprise to report!
I tested for a few hours the DSP TS870S-AT some weeks ago. Unfortunately I could only test it with 1296 beacons and on HF traffic due to time limitations. Now I got the change to test it on the moon.
It took me 3 x 2.5 minutes to find the signal of VE1ZJ. He is using a 3.7 m dish, and may be 150 W at the feed,. (Normally I copy just fragments with this type of setup.) Once I located the signal, I could improve copy somewhat by reducing the BW to 50 Hz, and by shifting the pitch to 500 Hz. There was no ringing. Then I tried the so called adaptive filter with short periods for the signal analyses. After a second of total silence, the two callsigns came up out of the noise in one string! Not one dot was missing. The noise had practically disappeared. This I would not have believed. (The former equipment was TS850 with a Timewave 59+ digital filter.)

I thought I had to report you about this experience. Maybe other small EME stations can test these new DSP rigs as well. I want to make one thing very clear, I am neither a shareholder of Kenwood nor do I have any commercial interest in amateur gear.(Those who are using the TS850 with transverters will miss the automatic low power response when injecting + 12 V dc through the coax into the transceiver. The TS870 does not offer this practical feature any more. I had to build a relay into the new rig to automatically bypass the final amp. when switching to the transverter)

Pease report here on your experiences with DSP in Weaksignal Communication.

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