| ATTENTION: The price shown includes Greek VAT 24% and is applicable to all individuals in EU countries only. If you are from any other country including USA, Canada, Australia etc. please use the "make offer" button and divide the price by 1,24.We will first accept this offer to let you proceed with the check-out and payment. If you are a business registered in EU with a valid VAT number again, you can use the same button so to pay without VAT. We will send you a zero VAT tax invoice. |
The design is successfully tested with around 15 dB gain from 0.5 to 30 MHZ and still has 8-10 dB gain on more than 55MHZ.
The outupt P1dB is +15dBm and it's noise figure is around 3 dB.
This amplifier can be used as a low-noise pre-amplifier in receivers or as general purpose wideband gain stage.
The two J310 J-Fets are biased at about 20mA each. The input transformer T1splits the input signal to feed both of the J-FETS in a balanced configuration, while T2 adds the two amplified signal together. This technique improves the 2nd order performance significantly, since all even harmonics cancel out. R1 and L1 form a negative feedback which affects amplifier's gain and frequency response.
Hello I just want to let you know how pleased I am with your preamp that you modified for the LF bands. It works very well, very clean with no images. The previous preamp I was using was a Hewlett Packard and it created a lot of images down the band. I am able to receive LW stations from Europe and I live 1500km from the Canadian coast. Very impressive preamp. Terry VE3XTM Guelph ON Canada.