Odd problem with Bush AC11, got me thinking.

[boater sam]

Thanks for that Lawrence, it sounds about right.

I was measuring at the hot end of the output transformer which is the reservoir cap connection, the HT rail after the smoother is only 67 volts, the smoother is a hefty 10K. So the drop with the AGC at maximum seems about right.
I wonder why I have never noticed this before?

The difference on tuning after repair was remarkable, like tuning in radio 4 after short wave! It was so sharp before and hard to achieve a mid point on the station.

[pwdrive]

Thanks for that Lawrence, it sounds about right.

I was measuring at the hot end of the output transformer which is the reservoir cap connection, the HT rail after the smoother is only 67 volts, the smoother is a hefty 10K. So the drop with the AGC at maximum seems about right.
I wonder why I have never noticed this before?

The difference on tuning after repair was remarkable, like tuning in radio 4 after short wave! It was so sharp before and hard to achieve a mid point on the station.

The Trader sheet gives the HT at the filter capacitor as 120 volts with no signal input, based on that your 67 volts seems low for whatever reason.

Lawrence.

[boater sam]

My error, that was at the anode of V3, UBC41, other side of the output coupling cap. Should be 60 volts there; but our farm mains can climb alarmingly when there is nothing on in the parlour, often over 250 volts! Its off our own pole transformer off a 5kV overhead. By the same token, it can drop to 215 sometimes, makes soldering a challenge.