Becos MICRO BOOSTER User manual

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THEMICROBOOSTERONBOARDPREAMP
INSTALLATIONMANUAL
SPECIFICATIONS
Inputimpedance:>1MΩ
OutputImpedance:~100Ω
FrequencyResponse:10Hz–30KHz(flat)
ToneStack:Centerfrequency720Hz,Lows+/‐6dB@70Hz,Highs+/‐
6dB@3.5KHz(nofrequencychangeincenterposition)
THD:0.2%(+0Buin/+15dBuout,1.0kHz,600ΩLoad,18VDCpower)
OptimalBatteryVoltage:9VDC±20%upto20VDC
RecommendedBattery:9VAlkaline(or2batteriesinseriesfor18V)
PowerConsumption:<0.1mAh@9VDC
ProductSize49.3mm(length),31.6mm(depth),27.7mm(height)
ProductWeight:54gr.
PackedWeight:160gr.
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ADVICE,WARNING&CAUTIONS
‐Readthismanualbeforeinstallationandkeepithandy.
‐Neverpullupthepush‐pushswitch‐potbyforce.
‐Removetheknobfromtheswitch‐potonlywhenswitchisinUP
position.
‐Donotattempttoremovetheshieldingcoveranddamagethe
board.
‐Donotoverheatthecircuitboardsoranyelectroniccomponent.
‐Ifsharptoolsaretobeusedininstallation,handlewithcareand
neveruseforcetohavethingsdone.
‐Wemaychangeproductsspecifications,design,andfeatures
withoutnotice.
INTRODUCTION
Built with monolithic amplifiers employing bipolar technology with
innovativehigh‐performanceconceptsforpristineaudio,theMicro
BoosterMK4hasanexceptionalfrequencyresponseandextremely
lownoise&distortion.
TheMicroBoosterMK4integratesaBaxandalltonestackwhichadds
flexibility for independent tonal tweaking of Lows and Highs. With
mildadjustabilityof +/‐9dB at 70Hz and2.5KHz beforethe0‐16dB
variable general Gain, it can be configured asa Clean Flat Boostor
Mid Boost, Treble Boost, Lows Boost, Boosted V‐Cut, etc. without
going into extremes. With tone knobs centered, the boost is
completelyflat.
Usually,aninstrumentiswiredlikethis:
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The booster will come latest in the guitar signal path, after the
pickups,volume&tonecontrols,pickupswitchandthemainsignal
willbefedthroughoneHotWireandGround.
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An optional Push‐Push switch‐pot may be soldered directly on the
electroniccircuitboard.Iftheswitch‐potisnotused,aDPDTswitch
mustbewiredtotheboardtoperformsignalroutinginstead.
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The potentiometer side of the switch‐pot IS NOT part of booster's
circuit,andismeanttoreplacevolumeortonepotentiometerin
yourinstrumentfortheconvenienceofhavingaroutingswitchanda
potentiometerinonedevice.Thepotentiometerhastoberewired
justasitusedtobe‐passive.Ifitisthetonecontrolthatisputin
placeof,thetonecapacitorhastobemovedtothenewpotaswell.
A 10‐pin header connector is available on booster's PCB where all
the wiring should be connected. Several wires can be directly
solderedtotheboard,ifapermanentconnectionisdesired.
A, B, C ‐ corresponding to potentiometer lugs (which will replace
actualpotentiometerinyourguitar).ThisiswherewiresGray,Purple
andBluewillbeconnected(thecolorsmaybedifferent,buttheyare
just wires connecting the new potentiometer to the rest of the
instrument’scircuit.Thesepinsintheheaderconnectoraredoubled
byconnecting holes on the circuit boardifsolderingthewiresmay
seem a better option. They also helpto install the capacitor or the
hotwire,dependingofwhereyouinstalltheboosterinyourguitar.
+and‐forconnectingthebattery.Redwireispositive,Blackwireis
negative.
RNG(ring),OUT(tip),GND with corresponding wires (usually
Orange, Red, and Brown) connectthenewTRS‐type(Tip,Ring,
Sleeve)outputconnectortothe board.Thisconnectorreplacesthe
originalTS‐typeofconnector(Tip,Sleeve)ontheinstrument.ATS‐
type mono jack is required to switch the power to the booster. A
TRS‐typeofjackwillnotwork.WhentheinstrumentcableTSjackis
inserted, the Ring to Ground in the connector is shorted by the
instrument plug’s Sleeve and the booster is powered (it stays
poweredregardlessofthepush‐pushswitchposition,upordown).
INandGNDarethepointswheretheHotWire(usuallyWhite)and
theGroundWire(usuallyBlack)willbeconnected.TheGroundWire
should be connected to instrument’s main ground. No other
groundingconnectionisneededtotheBooster.
Severalshortcutpointsontheboard(AtoGround,CtoGround,and
BtoInput)maybeusedtoavoidusingmorewires, whenpossible.
Simplyshorttheseinterconnectingpointswithadropofsolder.
Forsomesetups,theToneCapacitormaybeinstalleddirectlyonthe
booster’s board (in between BpotwiperandGround).TheTone
Capacitorcanonlybesolderedfromtheoutsideoftheboardwhere
thecapacitorismarkedontheboard.Donotattempttoremovethe
shieldingcoverbecauseyouwillriskdamagingtheboard.
PREPARATION
We recommend shielding the electronics compartment in your
instrument with conductive sticky cooper foil if it's not done from
thefactoryalready(aluminumworksbetterthannothing).Besure
to connect this shielding to guitar's main ground point. Shielding is
notnecessaryfortheboosterbutfortheloosewiresinthearea,
whicharenotproperlyshielded.Suchwiresmaybecomeanantenna
andtransfertheEMinterferencetothebooster.Youmayusethe
free Ground point on the booster board as the Main Ground Point
whereallgroundsaretobeconnected.
THENO‐POTBOOSTER

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THEMICROBOOSTERONBOARDPREAMP
INSTALLATIONMANUAL
Designed&HandMadeinRomania/EU
www.becosfx.com
Lastupdate:18July2022.
Checkanddownloadlatestmanual!
ThankyouforusingBECOSproducts!
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Theboosterwithouttheswitch‐potcanbeinstalledanywhereinthe
guitar.A DPDT switch is needed (notprovided)and it will be wired
with6wires(notprovided)totheswitch’ssixpointsonthePCB.
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INSTALLATION
Beforeproceedingwithinstallationtesttheboosteralone,outside
the instrument electronics. Simply apply a signal to the input (Hot
WireandGround)and connectthe outputto anamplifier. Thiswill
avoidthesuspicionthattheboosterisnotworkingproperlyiferrors
mayhappenfurtherintheinstallationprocess.
The installation should be performed by a skilled technician who
understandsguitarelectronics,wiringdiagrams,signalflow,andcan
performmodificationsifneededordesired.
We cannot and we will not make custom wiring drawings. We
provide the most common wiring examples from which you may
deriveaparticularconfiguration.Theseareavailableintheproduct
webpage.
Westronglyadviseyoutodrawandarchivetheoriginalinstrument
wiringforfuturereference.
Plan your custom installation on paper and when you are sure the
signalflowiscorrectthroughallthecomponentsusethatasyour
guidance.
Handworkingandsolderingarerequiredsobepreparedtospenda
fewgoodhoursoninstallation.Woodworkmaybenecessary–have
your tools ready. Proper mechanical, electric, and testing tools are
needed.
FINALTOUCH
The booster’s adjustment trimmers have a long sliding shaft that
goesthroughthetrimmerrotors.Theslidingshaftsadjusttheknobs
height when passed through the plastic back cover or through the
pickguardandallowflushalignmentatthetopofthebackplateor
thefrontpickguard.Knobholesneeda6mmbitandare10mm
apartfromeachotherinstraightline.Thetrim‐knobsarereversible,
ifthesettingsneedtobedonefromthefrontpickguardinsteadof
the back plate of the instrument. The direction of rotation forthe
trimmersisalsoreversedinthisinstance.Youmayfixthetrim‐knob
shaftsinthetrimmerrotorwithasmalldropofnaillacquer.Besure
thatyouwillnotlockthetrimmerrotors.Removethelacquerwitha
cutteriftheseneedreadjustments.Donotusesolventtoremove
thelacquerbecauseyouriskinfiltratingthetrimmeranddestroyit.
Removethewasherandonenutifthepotthreadlengthistooshort
to pass through instrument’s wood. These are the switch‐pot
dimensions.
AdjustingtheGain,Lows,andHighstrim‐knobsmayintroducestatic
noise,whichisnormalforthesetypesoftrimmerswhichare
intended for set and forget adjustments only. You may use a
contactscleaning aerosol solution (which also containa conductive
lubricant) to reduce or prevent the static noise or popping
occurrences while operating the potentiometer, trimmers, and the
sliding switch. Use a small puff of solution on each at a time and
performseveralmechanicalactionstohelpspreadingtheconductive
lubricantinsideoftheseparts.
The Micro Booster is configured for clean flat boost in all audio
spectrums for the given amplification headroom. Push the switch‐
potonce‐thesignalgoesthroughtheboostercircuit(theknobwill
goalittlehigher,soyouwillnoticetheboosterisengaged); push
againandthesignalisroutedinTRUEBYPASSstraighttotheoutput
of the instrument. The sliding DPDT switch side of the switch‐pot
mayintroducestaticnoise orpopswhenswitched, whichisnormal
forthesetypeofswitchesusedinsuchapplications.
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INOPERATION