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Thread ID: 125722	2012-07-15 02:34:00	LED Light Bulb Question - An Enigma, Really.	SurferJoe46 (51)	PC World Chat

Post ID	Timestamp	Content	User
1288571	2012-07-15 02:34:00	I own a really neat power conditioner for my bass amps and effects pedals and such, and it has two tubes that contain C7 incandescent bulbs that are always dying and burning out . So - I went and bought some kajillion-hour LED replacement bulbs in the same C7 configuration . They are really white, bright and show up nicely . There's a problem though . There's a dimmer potentiometer on the control panel to dim them or push them to 100% and since the LEDs don't pull the same power, they aren't able to be controlled by the pot . If I turn the dimmer all the way down and flip the rocker switch, the bulbs won't light up until I get about 50% of the knob turned, but from there on, the bulbs don't respond to any adjustment up or down at all . The old bulbs are 7½ Watts @ 120VAC . The new bulbs are 1 Watt @ 120VAC . My question is: is there a certain value resistor I can put in line to have the pot work like original to dim and adjust the brightness or do I have to change out the pot to get the results I need? Any ideas? I know this ain't rocket surgery, but Ohm's Law and I don't get along without a TI calculator (that's how long ago I played with current/voltage) and then it's iffy at that for any results I might get .	SurferJoe46 (51)
1288572	2012-07-15 04:37:00	Bulbs are for gardens ;) Steam age series resistance does not work so well with LED's, which tend to try and maintain a fixed voltage drop. To dim these, a pulse-width modulation technique is more usual (a chopper supply with a variable ratio of on time to off time). If in doubt, lamps can always be dimmed with a light smear of Vegemite; or you can eat the Vegemite, which makes you much brighter and so the lamps appear dimmer. Lucas LEDs are naturally self dimming by a long sitting tradition.	R2x1 (4628)
1288573	2012-07-15 04:49:00	Bulbs are for gardens ;) Steam age series resistance does not work so well with LED's, which tend to try and maintain a fixed voltage drop. To dim these, a pulse-width modulation technique is more usual (a chopper supply with a variable ratio of on time to off time). If in doubt, lamps can always be dimmed with a light smear of Vegemite; or you can eat the Vegemite, which makes you much brighter and so the lamps appear dimmer. Lucas LEDs are naturally self dimming by a long sitting tradition. Thanks for the accolade - but I'm not steam-age. Bronze-age is more like it. So ---- I need a PWM device to run LEDs at lower output? Hah! I knew it was too good to be good. Where - EXACTLY - would the Vegemite need to be spread? Don't toy with me - my wife has PMS and I know how to use it.	SurferJoe46 (51)
1288574	2012-07-15 08:44:00	Where - EXACTLY - would the Vegemite need to be spread? Don't toy with me - my wife has PMS and I know how to use it That is probably one of the most dangerous lines yet seen on PF1. I can only suggest you get your legs emulating the road runner as soon as possible - if it is not already too late. Wave as you pass New Mexico, but keep accelerating at all costs.	R2x1 (4628)
1288575	2012-07-15 08:47:00	Don't you spread Vegemite on your skin as sunscreen? Same as you use toothpaste as deodorant	gary67 (56)
1288576	2012-07-15 12:30:00	Vegemite is ideal for spreading on the skin, from the inside. If you use Veet as toothpaste, your hangover will be forgotten instantly.	R2x1 (4628)
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