07-10-2014, 02:02 PM
The Detrola I gave the link to above did exactly the same, and the radio is fairly close schematic-wise.
As for the droppers.....I need 6.2-6.5uF cap. I found that 6.2uF cap, metallized poly, and if I need to adjust a bit I add caps in parallel.
A diode and a resistor - the resistor will still have to dissipate 1/2 of the wattage of the heater cord which is about 15W, which is still a lot.
A capacitor and a diode can be used together but then you have to parallel the cap with a resistor and the RC has to be much shorter than the 16ms which is only possible if you need to drop a whole lot so your cap is small, or your resistor will dissipate a lot and it will defeat the purpose.
Anyways, I measured the current yesterday, with 6.6uF it gave me about 312mA which is pretty good, so 6.2uF will bring me to just about 300mA, and I did not see any spikes in current or voltage.
As for the droppers.....I need 6.2-6.5uF cap. I found that 6.2uF cap, metallized poly, and if I need to adjust a bit I add caps in parallel.
A diode and a resistor - the resistor will still have to dissipate 1/2 of the wattage of the heater cord which is about 15W, which is still a lot.
A capacitor and a diode can be used together but then you have to parallel the cap with a resistor and the RC has to be much shorter than the 16ms which is only possible if you need to drop a whole lot so your cap is small, or your resistor will dissipate a lot and it will defeat the purpose.
Anyways, I measured the current yesterday, with 6.6uF it gave me about 312mA which is pretty good, so 6.2uF will bring me to just about 300mA, and I did not see any spikes in current or voltage.
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