After using the RFSpace SDR-14 for quite a while, I've noticed some odd behavior. First is a minimal thing. The spike for an AM carrier seems to drop slightly when the unit is tuned to that frequency. Drops by a couple of db. When there are two adjacent stations at the same signal strength, the one it's tuned to is always slightly lower.
The second issue is one of noise. At least in this installation, it's a problem that blocks out weaker stations. When it's tuned above 490 KHz there is a wide noise level that covers hundreds of KHz. http://www.am-dx.com/Graphics/490.gif When I tune below 490 KHz it goes away. It does this consistently like an on-off switch. http://www.am-dx.com/Graphics/480.gif I thought there was a gain change, but that doesn't appear to be. I noticed a spur at 505 KHz that is at the same -90 level in both pictures. This is consistent across several antennas, including one outside on the tower. Anyone else notice this? Craig Healy Providence, RI _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
