golden eagle mkIII watts drop off

[stright razor-NYC]

i cant beleave this is happening i just got the dang thing working
good anyway when i key the transmit the watts start off at
4 watts and then some times when i key the watts fall back to about 2 watts then after a few keys its goes back to 3 watts swingin 4 bird watts. i was reading the manual and saw the bia
setting need to be in the box on the transmitter meter, i cant set the bias in the box, but it gets close. it say if u cant get the needle in the box then its possable that the tube is getting or is
flat.. 7558 tube..

[BionicChicken]

Try replacing the 7558 tube and the 12BY7A. I have seen the BY cause the problem with the wattage changing. But if you can't set the bias you probably need to change the final tube.

BC

[2600]

Have a VERY close look at all the resistors attached to those two tube sockets. Visible darkening around the middle, or a crack in the body means you need a resistor.

The relay could be it. If flicking it with your finger while keyed restores full power, you can try cleaning it with a strip of solvent-soaked paper.

If it's too worn, this won't work, or will work only for a while. Big PITA to change it. The original is made from unobtanium.

Just don't use ANY kind of abrasive on the relay contacts. This will destroy them and make sure that you need to replace it.

Never underestimate how much trouble that crud and oxide on the tubes' pins or on the tube sockets' contacts can cause. If gently rocking a tube in the socket while you're keyed causes the power to fluctuate, you need to clean BOTH the pins on that tube and that socket both.

73