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Anthem Integrated 1; blew EL84 and took resistor

Hello All,

My brother has an Anthem Integrated 1. The amp had been retubed back in April or so with JJel84's and various brands for the rest. Recently the amp had one of the EL84's blow and it took a nearby resistor with it.

Is there anything other than the EL84 and resistor that I should replace or be concerned about? I have attached some photos. Thanks in advance for any suggestions/help.

Thanks,
Dan
 

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The O/P tubes are matched pairs. Replace the failed EL84 and its "twin".

Be very grateful the failing tube only took a resistor with itself. :yes: It is anything but unheard of for costly transformers to be wrecked. :bawling:

UGH!

I am sure glad it didn't take a transformer! I will replace the pair of EL84's and the resistor in question. Is there anything in particular to look for to keep this from happening with the others? The tubes were only months old.

(I wonder, does anyone have a schematic or service manual for the Anthem Int. 1?)

Thanks!


Is there a schematic available? It might be wise to check the rest of the surrounding resistors as well.

I don't have one and couldn't find one online. I will keep looking though. I think I will check all the EL84's and associated resistors, thanks!
 
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What is written next to the burned resistor? Is it RC3? In this case, I'd guess it's the cathode resistor of the related tube and should be of the same value as RC4. Replace it appropriately. With the defective tube out, check the voltage at socket pin #2. It should be next to -15 Vdc. If it reads significantly higher (= closer to zero) or even positively, lift one leg of the grid coupling capacitor and check again. Or replace this capacitor just by suspicion. Then install a new tube and bias it according to the service manual.
Best regards!
 
What is written next to the burned resistor? Is it RC3? In this case, I'd guess it's the cathode resistor of the related tube and should be of the same value as RC4. Replace it appropriately. With the defective tube out, check the voltage at socket pin #2. It should be next to -15 Vdc. If it reads significantly higher (= closer to zero) or even positively, lift one leg of the grid coupling capacitor and check again. Or replace this capacitor just by suspicion. Then install a new tube and bias it according to the service manual.
Best regards!

Correct, it is RC3 and should be the same value as RC4. So check pin 2 voltage with defective tube out and all other tubes in, correct.

Thanks!