05-23-2012, 08:37 PM
Eric,
Don't you know by now that it does not matter what wattage a lamp pr bulb is? It does not matter what it is rated for: it will take exactly the current it needs as long as it is 6.3V that you give it, and if it is more wattage then it will keep blowing, until it blows the transformer. In your case there is no transformer.
You obviously give it more than 6.3V.
The bulb uses part of filament voltage, about 1/5th, 5 to 7v.
Measure the volts across the bulb, see what it is. From your voltages it should be 3V.
If it is, the inrush through the C11 may be a problem; see if it is what ir should be, a 40nF. Measure it. Maybe you recapped it wrong.
Also, though not likely, see if the bulb connected to pin8 i/o pin1; won't affect the rectifier but will low the bulb.
Don't you know by now that it does not matter what wattage a lamp pr bulb is? It does not matter what it is rated for: it will take exactly the current it needs as long as it is 6.3V that you give it, and if it is more wattage then it will keep blowing, until it blows the transformer. In your case there is no transformer.
You obviously give it more than 6.3V.
The bulb uses part of filament voltage, about 1/5th, 5 to 7v.
Measure the volts across the bulb, see what it is. From your voltages it should be 3V.
If it is, the inrush through the C11 may be a problem; see if it is what ir should be, a 40nF. Measure it. Maybe you recapped it wrong.
Also, though not likely, see if the bulb connected to pin8 i/o pin1; won't affect the rectifier but will low the bulb.
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