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With modern low-noise transistors, you can build an MC step-up with only one transistor.
The MC step-up is powered by a 12V lead-acid battery. The value of R4 depends on the hfe of the transistor used.
Transistor--R4 -- hfe -- Relative Noise for transistor
The brand of the transistor is very important. I found that Philips MPSA 42 and Philips BC 639 are 5-10dB more noisy than Motorola. Distortion of the amplifier is low due to local feedback. The gain of the amplifier is 19-20dB. If you have a problem with radio frequency interference, place a 22nH inductance in series with C1 and a 22pF capacitor in parallel with R4.
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