This simple low power triplicator was found in 90’s American documentation. The diodes can be general purpose types and the frequency is determined by the RC network of the 555.
This circuit generates pulses at a frequency that can be adjusted by a potentiometer. The circuit is...
This 1.5 A circuit is from the LM117 manual. The LM350 can be used for higher current, and the...
The circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor. Other...