Just out of the RF Lab, the receive chain with 25kHz IF is fully functional and initial testing shows a MDS (Minimum Detectable Signal) of better than -130dBm (0.07 uV). That’s before any process gain in the modem section. We will release complete Eb/No curves for the receiver prior to shipment.
Here’s a sample of the receiver performance at 440MHz. Dennis hooked a key up to his Agilent Sig-Gen. Note if you were actually working CW you’d add in a SW narrowband audio filter after the 25KHz IF stage.
This completes initial testing of the LNA thru the IQ XCVR and into the processor. The 100kHz IF stage needs some changes in the SAW filter circuit, so we can’t check that off just yet.