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Transistors BF-Serie - BF245

Datasheet BF245 Fairchild
http://datasheet.seekic.com/PdfFile/BF2/Fairchild_Semiconductor_BF245A37992.pdf
 
 

Klik voor vergroting136 kHz preselector and amplifier by IK2PII
This project was developed to reduce the image frequency response of my direct conversion receiver. It can also e useful as front end for HAM communications receivers and also for selective level meters used as LF receiver. The project focus was selectivity, not gain.
http://www.qsl.net/ik2pii/lf/prea136.htm

Klik voor vergrotingFKM QRP 5 Tranceiver door PA3FKM
Dit ontwerp heb ik gemaakt naar aanleiding van veel opmerkingen van Robert over diverse andere ontwerpen voor eenvoudige kortegolf tranceivers met klein vermogen.
http://pascal.nedlinux.nl/zelfbouw/FKM-QRP-5.html

Loop Pre-amp for LF by G3YXM
If you want to use a a small multi-turn loop on LF, you will find that the sensitivity is not good enough to receive the weaker signals. A good preamp for a loop needs to have a high input impedance and good signal handling characteristics (to prevent cross-modulation).
http://www.wireless.org.uk/circuits2.htm#loopamp

Pre-amp/filter for 136kHz by G3YXM
Most modern tranceivers cover LF but the performance is not always very good. All you can hear are strange whistles and burbles which aren't really there! You need this little circuit. It has a gain of about 10dB and a nice sharp band-pass response about 3kHz wide, enough to cover the 136 band.
http://www.wireless.org.uk/circuits2.htm#preamp

Klik voor vergrotingUsing a PC with soundcard as a VLF receiver by DL4YLP
This article describes how to use your PC as a receiver for narrow-band signals in the VLF radio spectrum.
http://www.qsl.net/dl4yhf/speclab/vlf_rcvr.htm


Creation date : 24/11/2013 @ 22:22
Last update : 09/09/2018 @ 23:59
Category : Transistors BF-Serie
Page read 24110 times


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