Mercury Epiphone Valve Junior User Manual

Epiphone Valve Jr.•Mercury Upgrade Kit 9
Thisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaff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.
Recommended tools for this project:
• SetofPhillipsscrewdrivers
• Wirestrippers
• Goodqualitysolderiron(capableoftempsat>800ºF)
• Electronicsgradesolder
• Soldersuckerand/orwick
• Dremel Toolwithpolishingandcarbidecuttingtips*
• ExactoknifeforcuttingandscrapingPCBtraces*
• Smallneedle-noseplyers
• Smallratchetset(AmericanandMetric)
Synopsis of Upgrade Sequence:
1. Disconnectchassisfromampanddischargethecaps.
2. Removeoldtransformers.
3. DisconnectMainandOutputPCBsandremove/
desoldercomponentsthatwillbechanged.
4. Drillnewtransformersandchokemountingholes.If
you’llbeaddingAlan’s6V6option,drillthesocketand
mountingscrewholesforthat.
5. Mounttransformersandchoke.Install6V6socketand
stand-offconnectorbracketifyouareaddingAlan’s
6V6option.
6. Drillholesforlamentwiresandenlargeholesfor
otherconnectionsintothemainPCB.
7. CuttracesonthemainPCB.
8. SolderbusswirejumperstothemainPCB.
9. Solderinupgrade’sresistorsandcapacitorsontothe
mainPCB.
10.MakeandsolderinlamentsupplyleadsbetweenV1
andV2(EL84and12AX7)sockets.
• Sharpknifeforscrapinginsulationlayerfromtraces
• Electricdrillwith1/16”and11/64”bits
• 1”and9/16”Varibitorsteppeddrillbit
• Silicongoo
• Loctite 290(green)
• PureisopropylalcoholandQ-tips
• Variacandcurrentmeter
*Dremel ToolcanbeusedtocuttracesanddrillholesinPCB.
11.Forthe6V6option,install8-pinsocket’scomponents
andconnectingleads.
12.SolderOT’sleadstotheoutput’sminiPCBand
reconnecttothechassis.
13.Completeconnectionstothe6V6option.
14.SolderremainingleadsforthePT,chokeandtheOT
tothemainPCBandtheOn/Offswitch.
15.ReattachmainPCBtochassis.
16.Usingthesupplieddiagrams,triple-checkyourwork
toensurethatallconnectionsaremadeandare
correct.
17.Powerupusingavariacandampmeter.
  CAUTION: DO NOT POWER UP THE AMP
WITHOUT THE SPEAKER CONNECTED!!!!
18.ArrangeleadstominimizeRFandnoise.
Reference photo of a stock Version 2 or 3 Valve Jr. chassis. Photo shows external chassis layout of
transformers and tubes. Note that hte EL84 and 12AX7 tube (or valve) sockets are identical. Be care-
ful NOT to accidentally switch these tubes!
Original Power Transformer
Generic EL84
Power Tube
Tube Retainers
Original Output
Transformer
Generic 12AX7
Preamp Tube

Mercury Epiphone Valve Junior Specifications

General

Brand	Mercury
Model	Epiphone Valve Junior
Category	Amplifier
Language	English