http://www.vmarsmanuals.co.uk/newsletter_articles/vibrator.pdf
Ahhh, yes looks like he doesn’t realize that his circuit is merely a bare bones DC configuration of an astable multivibrator.
The windings of the primary of the transformer serving as the collector load “resistors”, with just a wee inbalance of the
selection of the alternate collector / base feed back resistors to initially “nudge” the circuit into oscillation at power application.
Some enhancement in further driving the 3055 transistors FULLY into saturation could be obtained by the addition of a 2N2222
into each base circuit of each 3055 to evolve into a VERY high gain darlington configuration.
Additionally, if working with old “Ford, et al ” positive ground circuitry, one merely shifts their output transistor choice to the
“sister” PNP counterpart in the form of the 2N2955 power xstr, and companion 2N2907’s.
73's de Edd
Additional damping capacitors then will be needed to tame the ringing. Transformers don't like square waves and react badly when saturating. I prefer a "softer" oscillator which creates less noise on the secondary while using a controlled frequency. One might lose in efficiency but gain in quality. Although it may sound too fancy for the purpose as original vibrators were pretty harsh to the transformer already. They also failed quickly whence snubber caps quit working (of course, an exact value was mandatory for correct operation).
Syl