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7027A with tubelab simple se

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Guess I'm a little confused with this.
I've read that the 7027A is a direct drop in for a 6L6GC with two extra pins in the base.
Other threads say that you need to re-wire the socket, but it seems as though they are saying that when regarding an amp made for the 7027 and wanting to switch to a different tube.
My simple se blew up the 5AR4 tube (and fuse) on turn on with the 7027A on initial turn on.
I guess this amp is not supposed to run these tubes?
Paul
 
Pins 1 & 6 not normally used are used on the 7027A. Pin 1 is tied to Pin 4, and Pin 6 is tied to pin 5.
Could you just "cut off" pins 1 & 6 on the 7027 A?
Or, does anyone want some free 7027A's?
I'm not going to rewire any sockets or anything.
I already love the sound of this little amp with a variety of other tubes, I just wanted to hear some other tubes.
 
I'll take your 7027s!:D

They are actually identical to 6L6GC except for the base. I probably wouldn't start cutting pins- doing it sufficiently to prevent arcing to the socket will probably damage the tube. Check your socket wiring and pull off and move anything connected to pin 1 (often connected to pin 8!) and pin 6. These "spare" socket pins are often used as tie points in 6L6 amps.
 
The 6L6GC and the 7027A both have the heaters on pins 2 and 7. They both use pin 3 for the anode, and pin 8 for the cathode. So far, so good. Now comes the tricky part. The 6L6 has the control grid tied to pin 5, and the screen grid at pin 4. The 7027A uses pins 5 & 6 for the control grid. Pins 4 & 1 are for the screen grid.

On the Simple SE circuit board, pin 6 has no connection to anything. However, pins 1 and 8 are tied together. I believe this is necessary to get EL34 tubes working correctly. The EL34 has the suppressor grid connected to pin 1, while the 6L6 types have it connected to the cathode internally.

When you plug in your 7027A, now you've got the screen grid shorted to the cathode. That's sure to be bad news. If you have easy access to the bottom side of the board, you could probably just cut through the trace between pins 1 and 8, and then I'd expect the 7027A would work fine. Just remember the EL34 tubes won't work after you make this modification, unless you've got some way to put back the jumper from 1 to 8.
 
As several other observers have pointed out the 7027A is a 6L6GC on steroids. It does however have this issue with the extra pins. The problem arises with the G2 connection to pin 1. Yes, pin 1 is connected to the cathode to allow EL34's to work. Simply plugging a 7027A into the Simple SE connected the screen grid voltage to the cathode. This shorts the B+ to the cathode resistors. It looks like the fuse and the rectifier tube were the only casualties, but the screen stopper resistors and the cathode resistors probably got a quick surprise too!

7027A's can be made to work in the Simple SE by cutting pin 1 off of the tube (not recommended) or by cutting the trace on the back side of the PC board that connects pin 1 to pin 8 on the output tubes. If you do this, you can not use the board for EL34's. Since there is a bunch of voltage between these two pins make sure that you remove about 1/8 inch of copper between the two pins.
 
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