AL- 80B Works on and off

[KF5BQJ]

I have searched and have not found an answer yet.
The AL-80B is only about 3 years old. I drive it with Ft-897 going through Ameritron ARB-704. A few months ago it occasionally would not kick on and my swr is high, but on standby swr is ok. Also now on the meter, And while just idling the plate IP will jump up to about 100 and the Grid will go negative. Still sometimes when the meters settle down and it will transmit at normal power but sometimes the next key down no power. I have never over driven it. I run between 50-60 watts into the amp.
Thanks
KF5BQJ

[K1ZJH]

Sounds like a bad soldering connection in the metering resistors.

[PA5COR]

Bad or loose connection in or around the tube.

[W1QJ]

Any sign of plate current and negative grd current "IN IDLE" (not keyed) is a sign of an intermittant grid to filament short. Nothing can make the meters show any current otherwise. It's not a bad connection.

[WB2WIK]

Any sign of plate current and negative grd current "IN IDLE" (not keyed) is a sign of an intermittant grid to filament short. Nothing can make the meters show any current otherwise. It's not a bad connection.

Yep, that's what I'd say, too. Likely time for a new 3-500ZG.

[KF5BQJ]

Would this allow the amp to still perform with the same output as normal some time. ?

[WB2WIK]

Would this allow the amp to still perform with the same output as normal some time. ?

It surely could.

[AB1QP]

Bad or loose connection in or around the tube.

Ignore this reply. Mouse problems.

[WB2WIK]

Ignore this reply. Mouse problems.

I have some mousetraps that take care of that. Found they like peanut butter better than cheese.

[AF6LJ]

I have some mousetraps that take care of that. Found they like peanut butter better than cheese.

They also like In and Out Catchup.