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Hi;
I'm planning on making a parts order soon so I am compiling a big shopping list of resistors. In the service info I had for a model 96 there were no values listed for anything, only part numbers, I found the values on a schematic in the tech section of this website. However even though it has the values of the resistors listed it does not have the wattage of those resistors. I can take a guess about the wire wound resistors but what about the carbon ones, they all look like 1 watt or larger but that can't be right?
Regards
Arran
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Here is a link to philco resistor part numbers which should show the wattage for resistors by the part number. Hope this helps. Warren
http://www.philcoradio.com/tech/resistor.htm
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Unfortunately that system only applies to part numbers from 1936 and newer, my set is a 1930 model. I guess I will have to study the under chassis shots and compare them to what circuit they reside in, unless someone knows offhand?
Regards
Arran
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You're right, Arran, the carbon resistors in the 96 are 1 Watt. Philco had not yet started using any 1/2 watt resistors in any of their radios. As I recall, the first Philcos to use 1/2 watt resistors were the 70, 90 and 112.
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Ron Ramirez
Ferdinand IN
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So for safety's sake I should use 1 watt units throughout? What about the wire wound types? The big 8300 ohm bleeder (part #45) looks like it's at least a 15 Watt unit, but there is also an 800 ohm hum balancing resistor (part #41) that is probably a 10 watt and a pair of 70 ohm resistors in series (part #44) that also may be 10 watts. Since they used 1 watt jobs in the carbon resistors does that mean they would be more stable and less likely to drift? I think they may have had metal ends rather then having a wire wrapped around them? Or should I shotgun them all anyhow? I guess this also gives me an idea of what wattage of carbon resistors they used in the Radiola 44, they are big guys like the 96 has. Combine this with the poly film filter caps I will be using and these two sets will probably outlive me if I use 1 watters in them.
Regards
Arran
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I couldn't say offhand about the wirewounds without studying the circuit, the voltages involved, etc.
Only by measuring the resistors will you know how stable/unstable they are at the present time. Personally, I don't trust any 60+ year old carbon composition resistors, and I would, as you say, "shotgun" all of the carbon resistors if I intended to use the 96 frequently, or semi-frequently.
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Ron Ramirez
Ferdinand IN
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I agree whole heartedly.
"Done there, been that…"
Chuck
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Aye, only a few pennies apiece, and makes a big difference when you get the whole set together, align it, and set it right for many more decades of service. Best!
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If they are about 20-30% up I keep them and parallel them with additional resistor to bring them down. The new resistor is small amd I hide it behind the old big one.
Just for looks.
