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Philco 37-650 restoration
#1

Greetings, it's been awhile since my last restoration...
I am about to start a restoration of the 37-650 console, and I am trying to set up my material order list. I know I have to get to the hidden components under the RF sub-section which I will do first.. But, I need to order the components ASAP. First question I have of probably many to go and forgive my inexperience with this radio. The chassis houses a power resistor strip. It looks like 19 ohms and 119 ohms although the schematic is blurry. I want to replace that strip because the ohms were not stable and out of tolerance. I will go with a 20 and a 120 ohm resistor. My problem is I couldn't figure out the wattage of those resistors. I could go with 25 watts and call it quits, but that's not what I want to do.

Thank you for any help,

Vin
#2

I think the actual dissipation of the 109 Ohm one is about 1W and the 19 Ohm - 0.2W.
So if you go with 5W and 1W respectively, you should be fine.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

Thank you kindly, I just could not figure it out.

Vin
#4

Well,

I assumed that the total current should be around 100mA.

Both resistors in series conduct the total current.

100mA on a 109 ohm creates 1.1W dissip; and the 19 Ohm is roughly 1/5th of it which is 0.2W.
I use a factor of 5x to size up resistors. So it becomes 5W and 1W.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#5

Awesome! Thank you very much for the time and explanation.

Vin




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