Mercury Epiphone Valve Junior, Assembly Manual

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26
Epiphone V
alve Jr
.
•
Mercury Upgrade Kit
This
project
and
its
documentation
is
the
result
of
technical
investigations
made
by
the
engineering
staf
f of
Mercury Magnetics
. The
disclosure
of
the
information
herein
may
pertain
to
proprietary
rights
and
the
furnishing
of
these
documents
does
not
constitute
an
expresed
or
implied
license
to
use
such
materials.
6
5
4
3
2
1
8
7
T7 T8 T9
T3
V2
V1
T10 T11
T12
GND
C6
C9
C7
C8
T1
T2
D3
T4
T5
R10
R11
T6
B1
C12
D4 D1 D2
IN
G
IN S10 G
VALVE JUNIOR
VER051122
HBO1570
9
8
7
6
5
4
3
2
1
1
9
8
7
6
5
4
3
2
1 1
R12
R14
C3
C5
JP3
C4
R2
R15
R5
R4
R3
C1
R13
R1
R8
JP1
JP2
R9
R6 R7
C2
C11
VERSION: 07-30-08 (original)
REVISION: 02-12-09
www.MercuryMagnetics.com
www.Amp-Exchange.com
Copyright © 2008 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, 6V6 Mod and Mercury Upgrade are trademarks of Mercury Magnetics. Epiphone is a registered trademark of Gibson Guitar Corp. or its subsidiaries. Mercury Magnetics is not affiliated with Gibson Guitar Corp.
ON/OFF
SWITCH
Volume control attaches
to jack on underside of PCB
PT’s primary leads
(black and yellow)
PT’s
B+ leads
(red)
PT’s
center tap
(orange/
white striped)
(see inset)
INPUT JACK
MAIN PCB (inset, back of PCB)
VOLUME
CONTROL
PT’s
center tap
(orange/white
striped)
R16 R8 R4
GND
Chassis
Ground
AC &
FUSE
OT’s 4, 8 & 16
Ω
(green, yellow, grey)
OT’s ground
(black)
OT’s primary
(black)
Filament supply leads
(orange)
OT’s primary
(yellow)
PT’s filament leads
(orange)
Choke’s leads
(black)
OUTPUT PCB
MAIN PCB (see separate sections on prep)
6V6 Mod
(see separate section)
Valve Jr. head • Mercury Upgrade with 6V6 Mod
(Alan Cyr / Mercury Magnetics • Version 2 & 3 PCBs)
9167 Independence Ave., Chatsworth CA 91311 • (818) 998-7791
www.MercuryMagnetics.com • www.Amp-Exchange.com
SEQUENCE:
Note: Do not attach either the Output PCB or the Main PCB to
the chassis, yet. This schematic assumes that you have already
modified the chassis (with mounted transformers), Main PCB,
and setup the 6V6 Mod (see separate instructions).
1. Thread the various transformers and choke lead wires
through the original chassis holes as indicated.
2. Solder yellow and black leads from PT’s primary to the
ON/OFF switch as indicated (twist these leads).
3. Solder the 2 orange filament wires from the PT to the 6V6’s
pins #2 and #7 as indicated (twist these leads).
4. Solder OT’s primary black wire to T4 as indicated.
5. Solder OT’s secondary ground (black), 4 ohm (green), 8 ohm
(yellow) and 16 ohm (grey) output leads to the output PCB
as indicated.
6. Solder ground lead (black) from the 6V6’s standoff to the
Output PCB’s ground as indicated.
7. Re-attach Output PCB to the chassis.
8. Solder filament leads from 6V6 socket’s pins #2 and #7 to
the Main PCB holes at V2 you drilled earlier (twist these
leads).
9. Solder lead (blue) from 6V6’s pin #6 to R15 as indicated.
10. Solder lead (red) from 6V6’s pin #4 to R12 as indicated.
11. Solder lead (yellow) from 6V6’s pin #3 to V2’s pin #7 as
indicated.
12. Solder choke’s 2 black leads to R10 as indicated.
13. Solder the OT’s 2 B+ leads (red) to T1 and T2 of Main PCB
(DO NOT TWIST THESE LEADS!).
14. Re-solder original ground lead (green/yellow-striped) from
the chassis ground to the GND of the Main PCB.
15. Solder the OT’s center tap lead (orange/white-striped) to the
underside of the Main PCB as indicated by the Inset diagram.
16. Reconnect the volume control’s jack lead (underside of Main
PCB) and the input jack lead to the far end of the Main PCB.
17. Mount Main PCB back into the chassis.
18. Arrange wiring according to the instruction in the “Reducing
RF” section of this manual. Note that may take a little
finessing—you may have to trim and retwist the leads, or use
ties on some of the leads.
19. Triple-check your work.
20. Reinstall the tubes.
20. Proceed to instructions on using the variac and amp meter to
power the amp up. Debug if necessary and repeat this step.
21. Once operational, reassemble chassis in amp case, etc
22. Note: New transformers require about 20 hours of hard
playing to fully break-in—during this time you’ll notice subtle
improvements in the amp’s tone. It takes about 20 hours of
hard playing for the transformer set to achieve their “sweet
spot.”