liver pool el84 dying

[harris51]

playing my amp today, turned it off came back an hr later flipped the standby on and nothing the first three el84's were dead ,cold as ice the last one was red plating real bad put some spares in played for a minute and then same thing dead tubes_ help

[John_P_WI]

Interesting that only 1 in 4 is hot. When you say "cold as ice" are the heaters working? IF the red plating tube is the only one with heaters working it makes sense that it is red plating as the cathode resistor is not biasing the voltage up enough.

Otherwise, do you have a PPIMV? Other thoughts, check the 220k grid leak resistors, the PI coupling caps, the power tube cathode power resistor and cathode bypass cap.

I'm guessing it is in the heater string.....

[harris51]

fixed it it was that one el84 was not seated right so the other that followed where not getin power also

[rock_mumbles]

fixed it it was that one el84 was not seated right so the other that followed where not getin power also

That doesn't sound right ???

[harris51]

all I know is I jiggled the tube next to the one lit tube and the rest came on, go figure huh?

[strato17]

all I know is I jiggled the tube next to the one lit tube and the rest came on, go figure huh?

Sounds like you need to check your solder points. It seems like the heater wires may not be making a good connection on that socket.

[geetarpicker]

Strato17,
FYI PM sent.
Thanks!
Glen

[John_P_WI]

Not to be a skeptic, but IF you swapped tubes as stated above and had the same problem, there may be an intermittent problem waiting to happen.... Just FYI....

[Clyde]

You're having a time of it aren't you?

[harris51]

yes I will check al my solder joints and yes it seems to be Im havin a time of it, but nothing great ever came easy to me!