HPSDR Alex Filter Bank Prototype Test Results
These screenshots show the frequency response and return loss of the individual filter elements in the prototype HPSDR "Alex" filter bank product.Note that these are not directly comparable to the production unit measurements as the receive plots here show only the RX board without the contribution of the TX board's low pass filters. Scales may also be different.
S-parameter and magnitude files, as well as analyzer parameter files, for these measurements are available here.
RX 1.7 MHz High Pass Filter
RX 6.5 MHz High Pass Filter
RX 9.5 MHz High Pass Filter
RX 13.0 MHz High Pass Filter
RX 20.0 MHz High Pass Filter
RX 51.0 MHz Low Noise Amplifier/Band Pass Filter
(Drive level -40dBm to avoid compression)
System 55.0 MHz Low Pass Filter
Transmit Filters
TX 160M Low Pass Filter
TX 80M Low Pass Filter
TX 60/40M Low Pass Filter
TX 30/20M Low Pass Filter
TX 17/15M Low Pass Filter
TX 12/10M Low Pass Filter
TX 6M Low Pass Filter
(Network analyzer calibration did not support higher stop frequency; will
rerun after recalibration)
System Response
10M - ANT 1 to RX OUT
6M - ANT 1 to RX OUT; source level -40 dBm
Below are the original analyzer screenshots from which the combined plot was generated so you can see the marker values.
Here is the plot after adding the ground strap:
Penelope and Mercury Source Match
Penelope source match, at output BNC.
Mercury source match, at input BNC.