Quote:
Originally Posted by PJL
It looks like you are nearly there. Speakers of this age often have no dust cover over the voice coil and need a bit of a vacuum to get them free again. Rarely the spider needs adjusting. Take the speaker off and lets have a picture of the front of it.
The valve might have had a little bit of air in it after many years of disuse. The air is absorbed by the gettering when the valve is left runnning for a bit. You do need to keep an eye on it and should leave the set on for an hour with the meter connected and check the voltage stays low. The 42 gm is about 2.5mA/V so don't let pin 4 exceed 4V.
I still wonder if the AGC is working with the new bias arrangement. Tune into a strong station and try with a short aerial (a foot) and then a long aerial. The long aerial should sound best but if it gets distorted the AGC isn't working properly.
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Hi PJL spooky, Just got my tools out and was about to remove the speaker from the cab to have a look. will post a pic