I am trying to calculate Tsys for my 1.2m dish with Norsat 9000LDF LNB at 22GHz for water masers. Using SDR Sharp Signal Diagnostics I have obtained power level (amplitude really of 1.72 dB). I understand cold sky temp at 22 dB is 40K. Have I put the 1.72dB in right place and are results reasonable?

Yes, your spreadsheet is set up in the right way provided that the 1.72 dB is a power Y-factor. where (Y) must be a power ratio, not an amplitude (voltage)…

M-10047 M10047 ST RF Microwave Mixer SMA 6000-15000Mhz as part of my proposed 6.7 GHz maser receiver.

Would this successfully act as replacement for TERRASAT Microwave 6.4 – 7.1 GHz RX RF Mixer SMA ED-0280-1 MDC6471-035 ? https://www.ebay.co.uk/itm/205984985415?mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5339129536&toolid=20006&customid=958c8a6bc681104a2b53e0377cfda14b&loc_physical_ms=42038&loc_interest_ms=&msclkid=958c8a6bc681104a2b53e0377cfda14b To be a suitable replacement it needs to have:RF…