Hey everyone,
I’m building a receiver front-end for my amateur radio station and decided to use the SKY67151-396LF ultra-low-noise amplifier (LNA) (datasheet specs show NF ≈ 0.25-0.50 dB @ ~800-2500 MHz, gain ~19 dB, supply 3-5 V). It seemed ideal for boosting weak signals, but I’m running into a few minor issues. When tuned to UHF (~430 MHz band) the noise floor seems better, but when I switch to VHF (~144 MHz) the amplifier barely improves the signal and sometimes adds hiss. I’m powering it from a 5 V regulator that also supplies my SDR and mixer stage. I’m wondering if the shared supply or layout is undoing the benefit. The layout is compact but the LNA sits near switching regulators and long coax runs—could that be introducing noise or affecting the stability of the LNA?
How did you tune it / match it for VHF versus UHF? Any PCB layout or shielding tips you found made a big difference in hiss or unwanted gain?
Thanks in advance. I’m close to finalizing my build and want to ensure the front-end really performs.
I’m building a receiver front-end for my amateur radio station and decided to use the SKY67151-396LF ultra-low-noise amplifier (LNA) (datasheet specs show NF ≈ 0.25-0.50 dB @ ~800-2500 MHz, gain ~19 dB, supply 3-5 V). It seemed ideal for boosting weak signals, but I’m running into a few minor issues. When tuned to UHF (~430 MHz band) the noise floor seems better, but when I switch to VHF (~144 MHz) the amplifier barely improves the signal and sometimes adds hiss. I’m powering it from a 5 V regulator that also supplies my SDR and mixer stage. I’m wondering if the shared supply or layout is undoing the benefit. The layout is compact but the LNA sits near switching regulators and long coax runs—could that be introducing noise or affecting the stability of the LNA?
How did you tune it / match it for VHF versus UHF? Any PCB layout or shielding tips you found made a big difference in hiss or unwanted gain?
Thanks in advance. I’m close to finalizing my build and want to ensure the front-end really performs.
