04-13-2010, 02:58 PM
A fully tube functional radio will pretty much discharge most of the charge because current continues to flow after the set is off. Not so when there is no load. A capacitor is capable of storing a charge for hours, if not days. I use a 10K 2 watt resistor and test leads to discharge anything I'm working on. Leave this attached for at least 10 seconds to drain all the juice out.
And I usually install a "bleeder" resistor of about 100-or 200 K across the main resovoir as a further safety measure when I rebuild something. Two resistors in series, if the voltage is over 400 volts.
You should replace all the electrolytics and paper capacitors in the set before you apply any voltage to it. The cost is very little compared with the likelyhood of burning up an expensive tube or transformer. If you have to replace the wiring as well, I would probably go ahead and replace all the carbon resistors as well (you will find that in most cases they have increased in ohmage,) and this can make a big difference in performance once you are finally done with the set.
Good Luck
And I usually install a "bleeder" resistor of about 100-or 200 K across the main resovoir as a further safety measure when I rebuild something. Two resistors in series, if the voltage is over 400 volts.
You should replace all the electrolytics and paper capacitors in the set before you apply any voltage to it. The cost is very little compared with the likelyhood of burning up an expensive tube or transformer. If you have to replace the wiring as well, I would probably go ahead and replace all the carbon resistors as well (you will find that in most cases they have increased in ohmage,) and this can make a big difference in performance once you are finally done with the set.
Good Luck
