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Sideband · 22nd Feb 2013, 9:36 pm

You can't use a light dimmer as a variac

Reason? A light dimmer 'chops up' the AC waveform and effectively feeds pulses of AC to a lamp hence the light is dimmer. Just how many pulses (= mark/space ratio) are fed to the lamp depends on where the dimmer control is set. A TV will not like 'chopped up' AC.

Besides with the lamp in circuit, you don't need anything else. Suggest you use a couple of 60 watt lamp in parallel but don't bother with the dimmer.

Rich

22nd Feb 2013, 9:36 pm	#142
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,572	Re: My Bush TV43 restoration. You can't use a light dimmer as a variac Reason? A light dimmer 'chops up' the AC waveform and effectively feeds pulses of AC to a lamp hence the light is dimmer. Just how many pulses (= mark/space ratio) are fed to the lamp depends on where the dimmer control is set. A TV will not like 'chopped up' AC. Besides with the lamp in circuit, you don't need anything else. Suggest you use a couple of 60 watt lamp in parallel but don't bother with the dimmer. Rich __________________ There are lots of brilliant keyboard players and then there is Rick Wakeman.....