AC voltages way off specs - Please help explain this

[slidincharlie (Carlo P)]

There is something strange going on in my Silvertone 1472 amp if I compare AC voltages in the schem and in the chassis:
1) I have about 150 Vac (instead of 260) to pin 1-6 of the 6X4 recto, while the dc voltage out of pin 7 is perfectly in specs;
2) I have 2.7 Vac heater voltage (reading across the heater pins in any tube).
All dc voltages are perfectly in specs.
Is it a symptom of weak power transformer secondaries?
Should I take reading with the tubes off?

[Steve Conner]

Sounds like the AC voltage ranges on your meter are faulty. Try another meter.

[Dave Curtis, dB AudioTech]

There is something strange going on in my Silvertone 1472 amp if I compare AC voltages in the schem and in the chassis:
1) I have about 150 Vac (instead of 260) to pin 1-6 of the 6X4 recto, while the dc voltage out of pin 7 is perfectly in specs;
2) I have 2.7 Vac heater voltage (reading across the heater pins in any tube).
All dc voltages are perfectly in specs.
Is it a symptom of weak power transformer secondaries?
Should I take reading with the tubes off?

I know you said you're reading across the pins, but it looks like you're reading from the pins to ground.

[Bruce / Mission Amps]

I know you said you're reading across the pins, but it looks like you're reading from the pins to ground.

Across the 6X4 pins would be 520vac and with respect to the center tap, (grounded) would be 260vac.
Your meter could be way off... what is your primary line voltage... 117vac, or ?
You know that has to be close to right all the time, so check it against your meter.

[slidincharlie (Carlo P)]

I have just checked again.
The meter reads a solid 117 Vac mains supply at the power switch, so I guess it works.
I've re-read all Vac's and they read as above. Could there be a ground connection where it shouldn't, that cuts Vac's by the half? (please forgive my English...)

[slidincharlie (Carlo P)]

Fixed!

Sounds like the AC voltage ranges on your meter are faulty. Try another meter.

It was the DMM's 9V battery running low...
Sorry for stealing your time...
Thanks,
Carlo