Download - MEADE LightBridge: Encoders Installation - Astro Devices … · 2017-06-26 · Azimuth encoder installation ... , Astro Devices. ... Microsoft Word - LB Encoder Installation 01.docx

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MEADELightBridge:EncodersInstallation

Pleasemakesurethatyouhaveallthepartsincludedinthekit:

Listofparts:-thumbnutfortheazimuthpivot-spacer-azimuthpivotbolt-brassorplasticbushing-mountingplateforthepivotbolt-locknut-screwsforplate -threadedinsert(3/8”)andpush-inthreadedinsert(6.5mm)withanchorbolt-optionalwasherforthepivotbolt-azimuthtangentarmwiththeencodersensor-altitudeencodersensor-screwsforaltitudeencodersensor -magnetictapewithadhesivelayerforthealtitudebearing-encodercable-azimuthencoderdisk

Specifications:AzimuthEncoderresolution:311296stepsperrevolutionAltitudeEncoderresolution:952000stepsperrevolutionCurrentconsumption:25mAeach

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Pleasefamiliariseyourselfwithhowtheencoderswilllookinstalled(shownherewithouttheOTA):

Note:thephotoaboveshowsthebaseofLightBridge12”Deluxewithinstalledencodersandsomeadditionalwiringfordewheaters;thetangentarmshownisofpreviousrevisionwithouttensioningspring.Pleasenotetheplacementofthealtitudesensorandtheorientation

AzimuthencoderinstallationPleaseremovetheOTAfromthebase.Thenremovetheazimuthtensionadjustmentknob.

Youwillseeametalinsert.Youcaneitherkeepitoryoucanremoveitareplaceitwiththebushing


supplied.Pleasenotethatthebushingsuppliediseitherplasticorabrassbushing.Incaseyouwanttoreplacethebushingstartwithremovingthemetalinsert:

Theninsertthebushingprovidedandpushitintothehole:

Nowyouneedthewasherandthepivotbolt:

Putthewasheronthebushing:


Andinsertthepivotboltmakingsurethatyouscrewitintothethreadedinsertinthegroundboard:

Nowturnthebasearoundorputthewholebaseonaside:

Nowthreadtheplateontothepivotboltuntiltheplatecannotberotated:


Nowyouneedadrillandasmall2mmorsodrillbit:

Drillthreeholes–foreachscrew:

Younowneedascrewdriverandthreescrewsformountingtheplate:


Usethescrewdrivertofixtheplateinplace:

Nowputthebaseonitsfeetandusea½”spanner(or13mm)oranadjustablewrenchtoadjustthetensionsothetelescopedoesnotrotatefreely(asyouwillnotbeabletoadjustthetensionduetothelackoftheknob):


Nowturnthebaseonitssideandlockthepivotboltwiththelocknut:

Preparethetangentarm(10),thumbnut(1)spacer(2)andazimuthencoderring(15):

Feedthepivotboltthroughtangentarm’sballbearing:

Putthespaceronthebolt:


NOTE:Thetangentarmshouldbeinstalledfacingtheboardbetweensidewallsofthebaseofthetelescope.Puttheencoderringnow:

followedbythethumbnutandtightenit:

Youwillneedapencilforthenextstep:


Markthemiddleofthetangentarm’sslot:

Nowyouwillneedadrillandadrillbitofthefollowingsize:

- 6mmor¼”forthealuminiuminsert- 9.5mmor3/8”forthebrassthreadedinsert


Drillaholeatthemarkedspot,removethewoodchips:

Threadtheinsertintothehole(usearubberhummerincaseofusingthealuminiuminserttopushitintothehole):


Movethetangentarmuntiltheslotisoverthethreadedinsertandthreadtheanchorboltin:

AltitudeencoderinstallationItisimportanttofollowthestepsdescribedhereintheexactorderitisdescribed.Thealtitudeencodersensor(11)shouldbeinstalledontheinsideofthesidewalloftherockerboxthatdoesnothavethealtitudebearingtensionadjustment:

Youwillneedtousethesuppliedtemplatetomarktheplacementofthealtitudeencodersensor.Itisbesttouseaflashlightoranotherlightsourcetoplacethetemplatepreciselyontheinsideofthesidewall:


Theoutercircleofthetemplatemustbealignedwiththecircularlineofthewall(notthefeltlining):

Marktwomountingholesforthesensor–herethetwoleftholesareused:

Nowthemagnetictape(13)ofthealtitudeencoderneedstobeinstalled.YouwillneedIsopropylalcoholorsimilarsolventtocleanthesurfaceofthealtitudebearing:


Useapapertoweltocleanthepartofthealtitudebearingmarkedwitharedarrowinthephotobelow:

PuttheOTAonthebaseoncethesurfaceisclean:

Locatethebottomholeofthemarkedpositionofmountingholeofthealtitudesensoranduseapenciltodrawahorizontallineonthebearingalignedwiththemarkedpositionorslightlybelow:


Themagnetictapeisaveryspecialtapewithmultiplemagneticpolesmagnetisedwithahighdegreeofprecision.Thetapehasastainlesssteelbackingwithathinlayerofadhesive.Peeltheprotectivetapeofthemagnetictapeononeend:

RemovetheOTAfromtherockerbox.Themagnetictapeneedstobegluedverycarefullyontheinsideofthealtitudebearingstartingfromthelineyoumarkedinthepreviousstep.Forbestresultstheendsofthetapeshouldbegluedwithanepoxyglue(theadhesiveneedstobescrapedoffinthatcase).Hereonlytheadhesiveofthemagnetictapeisused.Useasoftclothtoputpressureonthetapewhileitisgluedinplacemakingsureitisfullyadheredtothesurfaceofthebearing:


Usethesmalldrillbittodrillsmallholesforthemountingscrewsmakingsuretheydonotgothroughtheholeboard:

Usethescrewsprovidedtoinstallthealtitudeencodersensor.Donottightenthemjustyet:


Thenextstepisveryimportant.Thesensor(asmallblackrectangleonthePCBmarkedwitharedarrowinthephotobelow)shouldideallybeplaceat0.5mmfromthemagnetic tape– it canbesmallerbut it shouldnot touch thetape.

PuttheOTAontotherockerboxandcheckthegapbetweentheactualsensorandthemagnetictape.Adjusttheplacementofthesensoruntilthegapis0.5mmorlessandtightenthescrews:

DONE!NotplugtheencodercableintothejacksoftheencodersandconnectittotheDSCandenjoy!