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BLF177 4M

BLF177 4M
 Now I found some time to make a decent drawing of my howework using SchemeIT  a nice on-line schematic drawing tool.  Offered by Digikey, did not find the BNC connector symbol. Digi Parts sells almost everything  it works simple and fast it comes close to the feel and touch of hand drawing. 
I have used ULTIBOARD  and before ORCAD .  But Ultiboard is to heavy and complicated for just drawing a small nice schematic.
R1 had to be a carbon type 0.5W this was essential to stop oscillations.
for R2  10x // 180Ohms metal are used here.  This schematic is partly a copy of Phillips application note
In the Phillips application R2 has lower value I did not try that.  A 10-5 Ohm carbon 1W  would do it there too I think.  

 




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