Wonderful day today for WSPR reception on 40m, mainly from PA & DL.
This is again using the set up of Arduino UNO, Concept DDS, and DCRX receiver. With a squatty small vertical indoor aerial.
SDRTX abandoned - now to be a QRP TXRX RIG
I have re-thought the SDRTX and decided to try for a more ambitious full QRP rig, a single board (shield) with an SDR RX and SDR TX on it, output around 10mW. This will be topped off with a three band BPF shield to work on 40, 30 & 20m.
Components researched and found for this are the FST3253 for the Mixers, and the SSM2135 dual op-amp for the audio side. This device is a new find for me and is a kind of super op-amp with very high output drive capability needed for the TX driver (4 channels into 50R loads).
Schematic later and PCB layout when ready. WIll probably breadboard the TX first as not yet got one running...
Decided also to move across to SMA connectors, these are much lighter but can handle up to 20W! and plentifull low cost cables are on eBay (SMA-SMA, SMA-BNC, SMA-PL59...).