Deluxe Reverb voltages

[tyler8611]

So I'm thinking bad reservoir cap or failing transformer. I've checked all the wiring and joints several times now. And I know it's not the tubes.

[tyler8611]

Per the schematic on a fender deluxe reverb aa763 (most will be within that range for 6V6) it calls for -35V so your bias pot should be able to dial it more negative than that as well. Say -40 or more. Then you can adjust according to taste after you measure and get the exact plate current. -15 is way too low of negative voltage and you're going to chew up tubes running that hot.

Sorry I couldn't help responding as that's something sluckey already stated setting this to max negative was important. You said you adjusted it but never reported what it actuall was. If you expect people to help, try and give them as much information as possible. I know from personal experience, sluckey is patient, but I led him on a few good goose chases because I wouldn't give him exactly what he was looking for. As sluckey reported, I'd not put those tubes back in until you can get the negative bias in a healthy range.

~Phil

I think your involvement here is counterproductive.

This is so out of line, Tyler. Phil is a moderator here and is trying to help. Why are you asking for help and then refusing it when it's offered?

I don't care if he's president. I don't tolerate condescending smart asses. Chill out fellas.

[sluckey]

I think you're on the right track now.

[tubeswell]

The 1.5R resistor is probably a 1R resistor with the meter leads adding 0.5R of measurement. What is the mV (DC) across this resistor? (We need to know this the calculate the tube current)

That reading is zero.

This reading needs to be (carefully) made with the voltmeter on the 'millivolt DC' setting, while the amp is switched on.

We use it to calculate tube current using Ohms Law, where: Voltage/Resistance = Current (written mathematically as E/R=I). Hence 1 Volt/1 Ohm = 1 Amp, and by reduction 1mV/1R = 1mA. So, if we measured (say) 25mV across this 1R resistor, that would calculate out as 25mA.

We need to know this in order to calculate plate dissipation (in Watts). Wattage = Voltage x Current. We need to know this to ensure that the plate is idling at a power dissipation that will not harm the output tube when the amp is under signal conditions.

[tyler8611]

The 1.5R resistor is probably a 1R resistor with the meter leads adding 0.5R of measurement. What is the mV (DC) across this resistor? (We need to know this the calculate the tube current)

That reading is zero.

This reading needs to be (carefully) made with the voltmeter on the 'millivolt DC' setting, while the amp is switched on.

We use it to calculate tube current using Ohms Law, where: Voltage/Resistance = Current (written mathematically as E/R=I). Hence 1 Volt/1 Ohm = 1 Amp, and by reduction 1mV/1R = 1mA. So, if we measured (say) 25mV across this 1R resistor, that would calculate out as 25mA.

We need to know this in order to calculate plate dissipation (in Watts). Wattage = Voltage x Current. We need to know this to ensure that the plate is idling at a power dissipation that will not harm the output tube when the amp is under signal conditions.

It was done with the amp running and the meter set to 200mv (DC) range. It read 0.0, just as it read 0.0 mA when I tested that range.

[tubeswell]

It was done with the amp running and the meter set to 200mv (DC) range. It read 0.0, just as it read 0.0 mA when I tested that range.

Then there can be no current in the resistors, and therefore (assuming the tubes were plugged in?), no current in the tubes.

Is there 6.3VAC between the heater pins (Pins 2 and 7)?