Peavey Ranger help

[Smokebreak]

This is the 2nd Ranger I've coincidentally seen in the last week.

This one came in with low power, and I initially misdiagnosed 2 non-conducting tubes in this 4 hole 120watter.

The amp works, but I knew something was wrong because I just worked on one that was tiptop when it left, and they are freaking loud. This one was a bit weak.

I just put a new quad of 6L6s and the for tubes, linearly speaking, named V5,V7,V6,V8.....tubes V5 and V6 sockets are not conducting. So basically, one socket on each side of the push-pull is not allowing current pull. Problem follows the socket.

I've attached the schematic that better shows the numbering system and may make better sense. The bottom 2 pages is what we're looking at.

Now, I've got screen voltage on the supply rail, but not on any pins 4. Of the 4 screen resistors, only 2 not reading, and they are on the non conducting sockets. It's kind of odd that the other 2 are reading ~100r, but still no voltage on the screens, but again, proper supply voltage on the other side. So essentially no tubes have anything on the screens, but I'm only showing 2 open screen resistors.

Of course making life more difficult is that the sockets are PCB mounted, upside down, and riveted to the chassis, so I'm doing all this with a damn dental mirror.

I've got good -50V on all grids. All cathodes are grounded. All plates read ~490V. All heaters working.

I'm gonna dig into it now, but thought I'd post because I need some help, and I know we all like these sluething adventures

Any Thoughts?

[Smokebreak]

So I replaced the two screen Rs : R207 R203
When I did that, all screen voltages came back, as there was none on any, previously, even though only one on each side was toast...
I don't understand that.

To compound my problems, one of the brand new JJs ran away on me, and was bad out of the box. I've got 4 good tubes in now and things seem to be holding steady.

[martin manning]

Very strange. I think I'd replace all four screen resistors and reflow all the solder joints between the screen supply and the socket pins.

[Stevem]

Better yet scrap back some of the soldering mask on the traces for atleast the plate and screen , grid and jump from there to the tube socket pins with a section of wire so even if the socket to foil trace goes bad you will still have a 100% connection.
This is the only way a have found to deal with many amps with the worst offender being Crate tube amps!

[Smokebreak]

Yes, odd indeed. Thanks for the suggestions and ideas, fellas.