UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Series connected stabilizer valves: questions

snowman_al · 15th Mar 2019, 10:33 am

Skywave,

First thought, apart from the obvious that they are 105 volt regulators, is do they all fully light when powered? You probably do not have enough voltage headroom to start with. Getting series regulators to strike and pass burning current can be a bit of an art, especially three in series...

You do not show your calculations so what current do the pull from your supply and what were you expecting?
Working on what you have and assuming they are all 'lit', 350 volts in and 315 volts 'regulated' out, so 35 volts drop, using your 4.7k limit resistor should see about 7.5mA? It might be necessary to actually add a small load to make it stable. A 100k, 1 watt resistor will load it by about 3mA.

So questions are, what stabilised voltage do you want and what current does it need to be?

Alan

15th Mar 2019, 10:33 am	#5
snowman_al Octode Join Date: Dec 2018 Location: Llandeilo, West Wales, UK. Posts: 1,092	Re: Series connected stabilizer valves: questions Skywave, First thought, apart from the obvious that they are 105 volt regulators, is do they all fully light when powered? You probably do not have enough voltage headroom to start with. Getting series regulators to strike and pass burning current can be a bit of an art, especially three in series... You do not show your calculations so what current do the pull from your supply and what were you expecting? Working on what you have and assuming they are all 'lit', 350 volts in and 315 volts 'regulated' out, so 35 volts drop, using your 4.7k limit resistor should see about 7.5mA? It might be necessary to actually add a small load to make it stable. A 100k, 1 watt resistor will load it by about 3mA. So questions are, what stabilised voltage do you want and what current does it need to be? Alan __________________ Never Leave Well Enough Alone...