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In all these common base preamp circuits it doesn't matter what type of base bias is used--I've seen a LED used in place of a standard 2 cent resistor, so using a 25 cent zener diode is just another way. The emitter resistor is varied to set the desired overall current.

I built the circuit just now; I used Steward fat toroids for the two transformers, but that doesn't matter much either. My bag of 3.3V zeners gave one that had an actual 3.0V; the final emitter current was 28 mA with the 13V supply shown--the circuit showed 31 mA so mine was close. I used a genuine Central Semi 2N5109. I used the 0.1 uF caps as shown. I used the DG8SAQ VNWA to measure gain and input/output impedances. My circuit had peak gain of +9.2 dB at 1 MHz; +9.0 dB at 10 MHz; +8.2 dB at 30 MHz. Input impedance was 23 ohms at 1 MHz, 27 ohms at 10 MHz, 45 ohms at 30 MHz. Output impedance was 111 ohms at 1 MHz, 116 ohma at 10 MHz, 150 ohms at 30 MHz. IMD with? 3 and 4 MHz test tones set for 0 dBm at preamp output: 1 and 7 MHz +60 dBm OIP2; 2 and 5 MHz +43 dBm OIP3. P1dB measured at 1 MHz with 50 ohm load: 0.12 watts = +20.8 dBm. HP noise figure meter, 10 MHz 3.75 dB noise figure.

I would say don't waste your time with this circuit. You could use a standard Norton circuit with much better NF, better in/out impedances for the same current as this circuit uses. Use standard resistor base bias. The article's goal was a decent HF-higher bands preamp for the old Atlas? 210 transceiver--the Norton would have been a better preamp circuit than this one.

73,

Steve AA7U