[Heathkit] Heathkit IG-42 Lab Signal Gen

[wendell rushton]

Went to use my IG-42 Gen and found it had no output signal. Took it out of the cabinet and everything look OK. Fired it up and it was working fine. Please note the metal cage was off the 6AF4 and  6AV5. Put it "'all " back together and powered it up,no output again. Must have done something when I put it back into cabinet. Pull out again and remover the cage over the 6AF4 and 6AV5 and tried it this time it was working just fine. I put the cage back on the tubes ,results "No output".
Any ideas  
Any help, please!
73, Windy   W4ZAA