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OK, when using a meter, there is no such thing as "no reading." The meter can indicate no continuity or infinite resistance, that is the reading can be the same as if you didn;t probe anything. But thay is not "no reading," that is a reading of "open." Likewise, if you see zero ohms, that is still a reading. So instead of "no reading," just report what the meter says, even if it indicates open. Follow the distinction?
If you put one meter probe on one end of that 1k resistor and the other meter probe at its far end, the meter would normally indicate 1000 ohms or some other amount. If the resistor is indeed open, then you get an open reading on the meter, or maybe very high resistance.
When measuring anything connected to capacitors, take the readings a second time, but reverse your probes end for end on the part. That is a hedge against possible remaining small voltage charges in the circuit confusing the meter. If your meter on ohms ever indicates "negative" resistance, that means there is some voltage left in the circuit. There isn't really negative resistance.
The orange gray orange resistor probably started life some other colors. orange gray is 38, a non standard resistor value.
Yes, your probes can make poor contact with oxidized wires. I always rub the edge of my probe along the wire to polish up a spot. Also probes are pointed for a reason, push the point into the soft solder some to improve contact. Nice probes are truly needle sharp. And they'll stick you.
The resistor that is 1k 5w is whet we call the screen node resistor, and it is not unusual for them to fail. Bad tubes will often damage that resistor. This is in any tube amp, not just this one.
At some point we will have to fire up the amp and see what it does. VOltage readings are taken with the meter black probe connected to ground, which is generally chassis.
If you put one meter probe on one end of that 1k resistor and the other meter probe at its far end, the meter would normally indicate 1000 ohms or some other amount. If the resistor is indeed open, then you get an open reading on the meter, or maybe very high resistance.
When measuring anything connected to capacitors, take the readings a second time, but reverse your probes end for end on the part. That is a hedge against possible remaining small voltage charges in the circuit confusing the meter. If your meter on ohms ever indicates "negative" resistance, that means there is some voltage left in the circuit. There isn't really negative resistance.
The orange gray orange resistor probably started life some other colors. orange gray is 38, a non standard resistor value.
Yes, your probes can make poor contact with oxidized wires. I always rub the edge of my probe along the wire to polish up a spot. Also probes are pointed for a reason, push the point into the soft solder some to improve contact. Nice probes are truly needle sharp. And they'll stick you.
The resistor that is 1k 5w is whet we call the screen node resistor, and it is not unusual for them to fail. Bad tubes will often damage that resistor. This is in any tube amp, not just this one.
At some point we will have to fire up the amp and see what it does. VOltage readings are taken with the meter black probe connected to ground, which is generally chassis.
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