NOMAD'S NOTES: Specific sections of the Valve Junior
R6/R7
http://www.sewatt.com/files/sewatt/r6-r7_0.pdf

Preamp Bias R8/R9
http://www.sewatt.com/files/sewatt/Preamp_bias_R8-R9.pdf

C5
12-22-07
http://www.sewatt.com/files/sewatt/C5.pdf

Adding a 6v6
1-26-08
http://www.sewatt.com/files/sewatt/Adding_6V6.pdf

HELPFUL LINKS
What do individual parts do in a Valve Junior?
The following "S2amps" link with info on the VJr version 1 amp is still pertinent and still considered one of the best resources. This document will help you understand what many of the common components do in the VJr as well as most tube amps. Some of the mods discussed in this link have evolved along with the VJr v2 and v3 amps. In other words, don't do the version 1 amp's heater mod to your v2 or v3 VJr amp!

http://rh-tech.org/public/S2_VJr_kit_inst.pdf

Also recommended for help in reading and understanding tube circuit schematics, as well as for being an excellent primer of what each part is and does in a tube circuit, DIY Stompboxes' Tube Terminology for Dummies

Audio Amplifier Circuits
Mullard - Circuits for Audio Amplifiers

Abbreviations used in tube data sheets
http://www.r-type.org/static/help.htm

BIAS, as in tube bias, what is it?
http://tubedepot.com/whisbipo.html

BIAS, biasing a VJr power tube, and/or tube amps in general

- note - Steve's diycustomamps Link Down - archived version still available -
http://web.archive.org/web/20071213061717/http://www.diycustomamps.com/v...

http://www.geofex.com/tubeampfaq/TUBEFAQ.htm#bias
http://www.aikenamps.com/WhatIsBiasing.htm
http://www.aikenamps.com/BackBiasing.html
http://www.aikenamps.com/Biasing.html
http://www.duncanamps.com/technical/lvbias.html
http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf
http://www.el34world.com/charts/fenderservice5.htm

Bias Calculators
The original VJr Bias calculator posted by Ronzo
slightly enhanced version
http://www.sewatt.com/files/sewatt/sewatt/files/vjr__bias_calculator.xls
parallel version
http://www.sewatt.com/files/sewatt/Vjr%20%20Bias_Calc%20Parallel_0.xls
Merlin's most excellent Valve Wizard Load Line Plotter for dual triodes,
see "Cathodes" below for more info
http://www.webervst.com/tubes1/calcbias.htm

Calculators, other
http://www.1728.com/resistrs.htm
http://www.electronics2000.co.uk/calc/
http://www.muzique.com/schem/filter.htm
Conversion Factors

Capacitors
How to Drain Filter Caps
http://www.amplates.com/images/AmplatesCapChart.pdf
http://www.aikenamps.com/CapConvert.htm
Auditioning_Tone_Capacitors Part I
Auditioning_Tone_Capacitors_Part_II
http://www.diyguitarist.com/GuitarAmps/FilterCapR.htm
http://www.harpamps.com/micKcaps/Forming-Capacitors.html
http://www.justradios.com/uFnFpF.html
http://www.justradios.com/captips.html
http://www.nmr.mgh.harvard.edu/~reese/electrolytics/
http://www.sbelectronics.com/images/PDFs/Outsidefoillocation.pdf
http://www.18watt.com/files/outer-foil-tester.jpg
HOW TO READ ORANGE DROP CAPACITORS
Premier Guitar Magazine's "The Life and Death of an Electrolytic Cap" by R.G.Keen
Vintage Capacitors

Cathodes: Understanding the Common Cathode, Triode Gain Stage
note: see page 27 for shelving freq rolloff
http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf
http://www.freewebs.com/valvewizard2/LoadLinePlotter.xls

Circuit Simulations
http://www.falstad.com/circuit/index.html

Chokes
http://www.aikenamps.com/Chokes.html
http://www.butlerwinding.com/inductors/common-mode2.html

Components and circuits in tube amps of all types and sizes
http://www.aikenamps.com/TI_Aiken_adv.htm
http://www.diystompboxes.com/pedals/tubedummy.html
http://www.geofex.com/tubeampfaq/tafaqndx.htm
http://www.hobbyprojects.com/tutorial.html
http://www.pacificrecone.com/JackDarrBook.html
http://www.pentodepress.com/index.html
http://www.tubecad.com/
http://www.tubefreak.com/tubefaq.htm
http://www.freewebs.com/valvewizard/
http://www.vintage-radio.com/repair-restore-information/

Construction Methods P2P-TB-PCB
http://www.aikenamps.com/PCBorPTP.htm
http://www.geofex.com/Article_Folders/pt-to-pt/pt-to-pt.htm
http://mhuss.com/AmpInfo/

Current Flow Through A Common Amp Circuit
http://www.el34world.com/charts/currentflow.htm

Current Limiters
http://www.diyguitarist.com/PDF_Files/AmpCurrentLimiter.pdf
http://www.geofex.com/Article_Folders/SPO_Test.htm
http://www.diyguitarist.com/GuitarAmps/FilterCapR.htm

Diodes of the Ultra Fast type (see also Transformer Info)
http://www.electronicrepairguide.com/ultra-fast-recovery-diode.html

Debugging squeals, hum, hiss, and pops etc.
http://paulrubyamps.com/info.html#FirstPowerUp
http://www.geofex.com/ampdbug/ampdebug.htm
http://www.lynx.bc.ca/~jc/hum.html
http://www.pacificrecone.com/JackDarrBook.html

Electronics Tutorials
http://www.hobbyprojects.com/tutorial.html
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
http://www.phy.davidson.edu/instrumentation/NEETS.htm
http://www.tpub.com/content/neets/14178/
AudioXpress, The Crowhurst Files
MIT EE Course

FAQs from other places
http://www.18watt.com/modules.php?name=FAQ
http://www.aikenamps.com/TechInfo_2.htm
http://www.ax84.com/faq.html
http://www.el34world.com/schematics.htm
http://www.radioremembered.org/tips.htm

Filters, hi-pass & lo-pass
http://mysite.verizon.net/ackman11/filters/rcfilters.htm
http://www.muzique.com/schem/filter.htm

Gain Reduction via Split Plate Load Resistors
http://www.blueguitar.org/new/articles/blue_gtr/amps/bp010629.pdf

Glossary of common amplifier terms
http://www.aikenamps.com/AmpTerms.html
http://www.diystompboxes.com/pedals/tubedummy.html
http://www.tubefreak.com/tubefaq.htm
http://www.about-guitar-amps.com/guitar_amps_terms_explained.html#Sag

Grounding
http://www.aikenamps.com/StarGround.html
http://www.geofex.com/Article_Folders/stargnd/stargnd.htm
http://www.paulrubyamps.com/info.html#StarGround
http://www.el34world.com/charts/grounds.htm

Hammond OT wiring
http://www.hammondmfg.com/125SE.htm
Hammond OT - VJr installation w/pics
How Do I Hook Up The OT (VJr Thread)

Harp Amps
http://www.planetharmonica.com/ph4/contents.htm
http://www.lwharpamps.com/
http://www.harpamps.com/
http://www.angelfire.com/music/harmonica/ampdamps.html
http://www.bluestime.it/harmonica_house/amp/hcharpamp.htm
http://www.jt30.com/blues_mics/harp_amp.html
http://www.jt30.com/jt30page/weber/Guitar51.htm
http://music-electronics-forum.com/archive/index.php/f-36.html
http://www.harpgear.com/nov07.html
http://www.modernbluesharmonica.com/board/board_topic/5560960/370319.htm
http://www.fjamods.com/Fender.html
http://bluesharpamps.blogspot.com/2008/03/harp-amp-project-fender-silver...
http://www.blowsmeaway.com/kalamazoo.html

Headphone Stereo Tube Amp with Slow Start and Relay Switching
http://headwize.com/projects/showfile.php?file=ahammer1_prj.htm

Hum, and how to get rid of it
http://www.lynx.bc.ca/~jc/hum.html
http://www.geofex.com/ampdbug/ampdebug.htm
http://www.ax84.com/faq.html#hp-trick

Input Impedance, Fender & Marshall's Hi/Lo inputs
http://www.18watt.com/files/high_and_low_input_theory_of_operation_2.gif

Lead Dress Tips for Wiring Amps
http://ayanmusic.com/leaddress.htm
Lead Dress in Tube Amps, by R.G.Keen,
Lead Dress - Point to Point versus PCB amps, by R.G.Keen

Ohm's Law
http://www.aikenamps.com/OhmsLaw.htm
http://www.radioremembered.org/ohmslaw.htm

Pedal info
http://www.diystompboxes.com/smfforum/
http://www.geofex.com/
http://www.beavisaudio.com/
http://www.runoffgroove.com/
http://freestompboxes.org/
http://www.tonepad.com/
http://www.generalguitargadgets.com/
http://www.muzique.com/
http://www.pedalheaven.com/
http://www.big-muff.net/
http://filters.muziq.be/

Potentiometers
Potentiometer Taper Charts - Resistance Versus Rotation
Premier Guitar Magazine's "The Log and Short of Tapers"

Relays
http://www.geofex.com/Article_Folders/relays/relays_for_switching_audio_...
http://www.geofex.com/Article_Folders/remoteftsw.pdf
http://www.el34world.com/projects/relay_switch.htm

Resistors
How to Read a Resistor
http://www.radioremembered.org/rescode.htm
http://www.aikenamps.com/ResistorColorCode.htm
http://aikenamps.com/ResistorNoise.htm
http://www.1728.com/resistrs.htm
http://www.breakup.de/resources/resistor.html
http://www.electronics2000.co.uk/calc/calcrsp.htm
http://www.geofex.com/Article_Folders/carbon_comp/carboncomp.htm

Resistors and Capacitors together
http://mysite.verizon.net/ackman11/filters/rcfilters.htm
http://www.muzique.com/schem/filter.htm

Reverb Tanks
http://www.ampwares.com/reverb_codes.html
Adding Reverb (VJr Thread)

Schematics
Tube Terminology for Dummies
How To Read A Schematic Diagram
http://www.18watt.com/
http://www.ax84.com/
http://blueguitar.org/
http://www.el34world.com/charts/Diagrams.htm
http://www.kbapps.com/schematics.html
http://www.schematicheaven.com/

Schematic Symbols
http://www.aaroncake.net/electronics/schem.htm
http://www.hobbyprojects.com/general_theory/circuit_symbols.html
http://www.kpsec.freeuk.com/symbol.htm
http://www.symbols.net/electrical/
http://openbookproject.net//electricCircuits/Ref/REF_9.html
http://www.educypedia.be/electronics/dataschematic.htm

Screen Grid Resistor Mod - VJr Thread
http://www.sewatt.com/node/19533

Soldering Tips
http://www.epemag.wimborne.co.uk/solderfaq.htm#howto
http://www.buildyourownclone.com/board/viewtopic.php?f=31&t=6430&start=0...
http://www.mercurymagnetics.com/images/pdf/How_to_solder.pdf

Speakers
Speakers.PDF - Load Matching and Mismatching Hook-Up Guide
http://www.radioremembered.org/edspeaker.htm
What Happens if... ? - VJr Thread
A Brown Sound/Tone Tubby Speaker Wiring and Load Charts
AES' Speaker Ohm Rating and Wiring
Celestion Speaker Wiring Diagrams and Cab Loading Info
EV speaker cab Build Plans

Switches
Power Switch 101 - VJr Thread

Technical books
http://www.wattkins.com/books
http://www.aikenamps.com/Bibliography.html
http://www.amptone.com/booksamps.htm
http://www.pmillett.com/technical_books_online.htm
http://www.pacificrecone.com/JackDarrBook.html

Technical Field Guides
http://workmanship.nasa.gov/lib/insp/2%20books/frameset.html
http://www.rru.com/~meo/Guitar/Amps/Kalamazoo/
http://www.ampwares.com/ffg/
http://www.pacificrecone.com/JackDarrBook.html
http://www.pentodepress.com/index.html
Electronic Vacuum Tube Reference Manual & Specifications from the RCA Receiving Tube Manual

Transformer Info
http://www.ax84.com/faq.html#hp-trick
Valve Junior Power Transformer Specs
MPS's OT10SE transformer wiring diagram
http://www.hammondmfg.com/pdf/5c007.pdf
Pvsage's Hammond PT Rectification Voltage Chart
http://www.jensen-transformers.com/an/Audio%20Transformers%20Chapter.pdf
http://www.powertransformer.us/
http://www.ozvalveamps.elands.com/repairs/trannytest.htm
http://www.radioremembered.org/xfmr.htm
http://www.radioremembered.org/outimp.htm
http://www.geofex.com/FX_images/xform_test.gif
Premier Guitar Magazine's "Super-Secret Transformer Tester" by R.G.Keen

Tone Stacks
BitMo Tone Stack
http://www.duncanamps.com/tsc/
http://amps.zugster.net/articles/tone-stacks#Garnet

Tube Amp Design
http://www.pmillett.com/Books/GEC_approach.pdf
http://www.freewebs.com/valvewizard/index.html
http://www.aikenamps.com/TechInfo_2.htm
http://www.audioxpress.com/resource/audioclass/
http://www.pentodepress.com/index.html
Radiotron designers handbook 3rd edition - 16 mb
Radiotron designers handbook 4th edition - 25 mb

Tube Data Sheets
http://www.sewatt.com/node/16285

Tube Pinout Guide
http://www.amplates.com/images/AmplatesTubePinouts.pdf

Tubes, the Universe, and Everything
http://www.sewatt.com/node/16285

Turret Installation... the fast way, recommended by Bigbeck
http://www.el34world.com/charts/toolhowto.htm
the old slow method
http://www.turretboards.com/tut_building_turret_and_eyelet_boards.htm
http://www.paulrubyamps.com/TurretHowTo.html

Vintage Voltage Adapter
http://www.geofex.com/Article_Folders/vintvolt/vintvolt.htm

Variable Voltage Regulator
see Schematics and Latest Valve Junior mods

Wire for Tube Amps and Color Code suggestions.
http://blog.tubedepot.com/?cat=12
http://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity