5150ii burned resistor / possible arcing

[Sowhat]

Ok, new tube socket is in, new 4.7k for r69
The NTC isn't going to be here for a few days.. Will I be OK firing it up, or is the current limiting that important to use every time.

Dampening inrush current is never a bad idea but it's not necessarily necessary pretty much as long as you don't make a habit of it. Straight to the mains? Gulp!, go ahead and see what happens... although personally, I would not bring up a new tube amp repair without ramping up slowly using a variac or short of that, a lightbulb limiter... just in case. Let me know what happens after the smoke clears.

[Sowhat]

I'm thinking you know this already, but maybe not, anyway, that Thermistor is in series on the primary side of the power transformer so... this would necessitate jumpering it's pins to complete the circuit so that you can plug the amp into the mains and get juice. I just hope it don't drink too much.

[wormdirt]

I was more wondering whether it is a safety measure or a necessary component. I'll wait till the new one shows up, but flip it on fever has caught me pretty hard

[Enzo]

Inrush limiters, if nothing else are easier on your power switch. Discharged caps, like when you first power up in the morning, are short circuits to the power supply until they charge - a second or two. That stresses rectifiers. Inrush limiters help relieve the amp of that stress.

[wormdirt]

Ok, new components in, amp reassembled
flip it on and light bulb limiter is bright as hell.
mains voltage is only at 50v ac
scratching my head
If mains is only at 2v then I guess checking voltages is out of the question

[Sowhat]

If mains is only at 2v then I guess checking voltages is out of the question

I'm so glad you used a limiter, it saves a lot of grief. As I know it so far this is a new manifestation, right? It didn't behave like this before you did your fixing, the problem was something else with R69 burning?

Well, you got a short and you need to go on a short hunt with your ohm meter and the power off, of course. I would suspect the work you just did first, I know you took great care and were patient installing the new parts but even seasoned veterans can create hidden solder shorts or even miss removing wire clippings... a prime reason for using a limiter for first startups.

My prayers are with you and the only advise I can give is to isolate and compartmentalize your search... whatever that means, right? I think you get the idea.

BTW: You did use new tubes, didn't you?

[wormdirt]

Ok multiple bonehead moves in a row.
Excitement is definitely the excuse I'm gonna use.
1st bad move: I fired it up with power tubes in
2nd bad move: I fired it up with 7027acz's in it and not 6l6s

Put the right tubes in, tested it and everything is hunky dory.

Plays fine, not even that noisey at full gain.

Thanks guys haha what a day

Summary:
Peavey 5150ii
Burned r69, arcing on power tube socket, cracked thermistor
Socket/screen grid resistors/ r69 replaced / thermistor replaced with equivalent components
Works.

[Sowhat]

Thanks guys haha what a day

Excellent, you did it!

[g1]

This is one of those instances that you can't use a 7027 instead of 6L6.
Peavy runs the plate voltage to pin6 of one of the power tube sockets. In a 6L6, pin6 is disconnected, so no problem. In a 7027, pin5 and pin6 are both the control grid. So the grid of that 7027 got full plate voltage to it. I think that one will probably be toast.