What do I trust?
? What do I trust?
I am renovating an Ekco U243 and have conflicting information. The schematic shows a resistor to be 22k but physically the resistor is colour coded, and measures 3.3k. the resistor is original and not a replacement. It's a general question, not limited to this model. Which do we trust, the schematic or the original fitted component?. I would tend to trust the physical, I am not technically proficient enough to know what it should be in the circuit.
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What do I trust?

It is my experience that within time of the production of a radio set there are improvements and changes. Experiences in the market or also changes of delivered parts may be the reason.
These changes may be documented in the published diagrams or not. Sometimes not all of the diagrams of the different versions are available in radiomuseum.org. Sometimes you may find marks on the documents like "valid from production no. abc to no. xyz" or something similar.
If you are really sure that the resistor in question has not been changed within the decades and is not a replacement I would trust in the dimension of this resistor.
Within time you will get more knowledge about the possible correct value. It would help if you named the resistor so that specialists here in this forum may give some comments. Start your question from the model page.
If you are talking in this case about R28 "tone correction" the lower value of 3.3 kOhms simply increases the effectiveness of the tone correction and cuts the high frequency components of the tone.
Rüdiger Walz
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What do I trust?
Great, thanks Rudiger.
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