MAX9814 seems the best choice it has AGC and jumpers for gain setting to max 60dB will test this one to when arrived.
Received this low noise ST TS472 pre-amp Diymore from eBay.
Main while the 3 transistor pre-amp with AVR earlier down in the blog works fine.
This TS472 IC is special designed for microphones electret or magnetic and i was curious to find out how such integrated device performs.
With the magnetic 200 OHm Peiker element the signal is fine although not as sensitive as with an electret element. The maximum un-clipped output is about 2Vtt.
It did not match the low impedance mike input of the Condor as it is at first test.
Minimum drive load is 10k.
An emitter or source driver is needed behind the TS472 and low impedance tranceivers like the Condor.
No documentation is supplied with it but the PCB looks similar to the
ST demo board TS472 PCB well designed.
The standby pad must be + , minus = gnd will switch to standby.
Left floating wil drift it uncontro…
matige propagatie maar toch FT8 VP8LP Britse kolonie en Tasmanië WSPR
No.Date UTCBandCallsignQTHOperatorModeRSTs1.2017-12-1800:1180 m VP8LPFT8-152.2017-12-1718:1480 m VK7DIK- Ulverstone,Tasmania [ Australia ]DickWSPR-183.2017-12-1606:39160 m IS0GFTFT8-114.2017-12-1606:34160 m F4HQLFT8+105.2017-12-1606:19160 m XE1HFT8-166.2017-12-1600:1980 m PZ5RAFT8-177.2017-12-1508:1480 m KG6MCFT8-158.2017-12-14