Voeding gitaarversterker (Techniek Overig)

door rkamp , Den Haag, 12.05.2020, 19:38 (1654 dagen geleden) @ Robert Gribnau

Waar ik niet helemaal zeker van ben, is of de weerstand van 100K, die nu uitkomt op de verbinding tussen de twee ZZ1040's, inderdaad nodig is om de beide ZZ1040's volledig te ontsteken.

Nodig niet, maar wel aan te raden, in de meeste referentie datasheets word het onderstaande stukje vermeld.
De ontsteekspanning zou in dit geval zonder deze weerstand boven de 250V uitkomen(in duisternis), met deze weerstand word de ontsteking dus geholpen.

Overgenomen uit datasheet "Philips Voltage reference and stabilising tubes 1966":
Series-connected stabilising tubes can be ignited with a supply voltage lower the the sum of the ignition voltages of two or more tubes, by using a bypassing resistor(Rp) having a value in the order of 0,1 to 1 MOhm.
Due to the load current flowing through Rserie and Rload before igniting of the tubes,
the voltage at point a(Anode bovenste referentie) can be lower that the sum of both tubes.
The junction of both tubes(point b, Anode onderste referentie) is kept at potential of the supply voltage, and, provided V exceeds the ignition voltage of the lower tube under worst case conditions, this tube wil always ignite.
As a result the voltage across the lower tube drops to the value of the maintaining voltage, thereby lowering the potential of point b. The voltage of the upper tube is then high enough for it to be ignited.
The same method can be applied to be ensure the ignition of a single stabilising tube, by connecting it in series with a semiconductor diode.

Gr. Remko.