Also need help with a maco 300 ,But orange face
I have an orange face later model maco 300 using the 5- 2057's as soon as i turn it on the tubes randomly turn blue and then after a minute or so start glowing orange. i have checked all the tubes on the tester and show no shorts . i have even only put 2 of the 4 finals in and get the same results . also depending on where i turn the air-variable caps at a certain point the transmit light comes on , but obviously the relay is not engaging and there is no exciter. my first thought was a short to ground on a cap at a socket so i have removed each one , one at a time and checked for short but none. Could it be a bias problem? Also if i try the amp out quickly without leaving it on too long it does work and good numbers too , but when i get it tuned it is at the point where when i un-key it has no receive and the transmit light is on. Any help would be great , especially since i can't find the schematic on the orange face version . Thanks