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RCA 6K3 Preliminary Capacitor/Resistor Research
#9

Hi Roy, Arran beat me to it and with really good info. How to proceed depends on whether you are trying to produce a museum quality piece where you hollowed out all the original caps and used the casings to hide the new caps (called "stuffing" caps) or if you only care about everything above the chassis to look vintage and the underside can look new. The resistor we are discussing, RCA P/N 11466is a "Candohm". This resistor based voltage divider supplies the various "B+" voltages and the bias voltages for the 1st AF and Output tubes. Note that chassis ground is not the most negative point in the power supply. The center tap of the HV section of the power supply is. Please note that the negative lead of the Caps C30 and C31 does NOT go to chassis ground, the negatives go to the center tap of the HV secondary of the transformer. The negative of C16 DOES go to chassis ground. BTW, as Arran stated, the Aerovox 20/20 uF cap shown in the picture is definitely a replacement. The Parts list shows 3 different P/Ns for the 3 electrolytic caps.

You can leave the cap mounted but cut the wires from the under-chassis connections and replace these with modern caps under the chassis.

In either case I would completely replace all resistors in this voltage divider. (R13 through R18). Granted, the section that blew dissipated the most heat and power as it had the highest resistance, however, it's like headlight bulbs in the car. If you have to replace one, you will be doing the other really soon.

I think that the easiest and most reliable way to replace these resistors is to remove the Candohm (Drill out the rivets), mount a terminal strip or 2 and use 10W ceramic resistors. Dress these so they get as much ventilation as possible and keep them as far away from other devices as possible. They can be placed against the chassis and allow the chassis to dissipate heat, especially if the voltage divider resistor was a metal enclosed resistor ("Candohm") mounted against the chassis. DO make sure that you connect the wires routing the resistor correctly. Alternatively, get the aluminum encased resistors that Arran referred to as "Arcol" resistors and mount them on the chassis, or on a metal plate that you then mount to the chassis.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


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RE: RCA 6K3 Preliminary Capacitor/Resistor Research - by MrFixr55 - 04-15-2026, 08:58 AM



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