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Showing posts from December 18, 2017

TS472 microphone preamp versus MAX9812

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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…

80M DX

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matige propagatie maar toch FT8 VP8LP Britse kolonie en TasmaniĆ« WSPR HAMLOG.EU  http://www.hamlog.eu                                                                   HAMLOG.EU



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