2xecc83-ef86 2xel84.pdf

Schematics, Templates,

And Parts Layouts

Schematic- 12AX7 input tube

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Schematic - EF86 input tube

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Wiring and Layout Template - 12AX7 input tube

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Wiring Template - EF86 input tube

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11 Cool Modifications

Install a GZ34 in place of the EZ81

The GZ34 provides more solid dynamics creating less

“sag”. With an octal socket you can also experimentation

with many different types of rectifier tubes such as 5Y3,

5V4, 5R4, etc.

photo 11a

Step 1 – Cut a hole in the chassis (in place of the original

9 pin hole) large enough to accommodate an octal

socket. Drill the two mounting holes and install the octal

socket.

Step 2 – Connect the two yellow filament wires from the

power transformer to pins 8 and 2 of the octal socket

(photo 11a).

Step 3 – Connect the two red wires (HV) from the

power transformer to pins 4 and 6 of the octal

socket.

Step 4 – Connect the B+ wire from the standby

switch to pin 8 of the octal socket.

Step 5 – Install the 5AR4.

Upgrade the normal channel input

tube from a 12AX7 to an EF86 -

An EF86 gives a more transparent high end and

tighter low end … very “VOX” sounding.

The wiring layout at right (drawing 11a) shows the

proper components and wiring diaram for the

conversion.

drawing 11a

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