[Samsung Galaxy J2 Questions & Answers] Sam_S3:
Poor Signal issues signal come late or whatever..If ur phone rooted..please try these special build.prop tweaks for j2....

# Better Responsiveness & Speed

windowsmgr.max_events_per_sec=300

ro.max.fling_velocity=15000

ro.min.fling_velocity=8000

ro.min_pointer_dur=8

touch.pressure.scale=0.1

# More RAM

#persist.sys.purgeable_assets=1

persist.service.pcsync.enable=0

persist.service.lgospd.enable=0

#Hardware Power Saving

ro.config.hw_power_saving=1

#Disable Miscellaneous Android Logging Stuff

debugtool.anrhistory=0

profiler.debugmonitor=false

profiler.launch=false

profiler.hung.dumpdobugreport=false

#Enable ADB Debugging By Default & Disable USB Debugging Popup

persist.adb.notify=0

persist.service.adb.enable=1 persist.service.debuggable=1

persist.sys.usb.config=mtp,adb

#Disable Logers

ro.config.htc.nocheckin=1

ro.config.nocheckin=1

#Disable Kernel Error Checking

ro.kernel.android.checkjni=0

ro.kernel.checkjni=0

# Reduce dial-out time

ro.telephony.call_ring.delay=0

ring.delay=0

# Other Tweaks:

ro.config.combined_signal=true

#DHA tunning

ro.config.dha_tunnable=1

#Disable Strict Mode Checking

persist.android.strictmode=0

#Better signal reception

persist.cust.tel.eons=1

ro.config.hw_fast_dormancy=1

#For Sensor Sleep Control

ro.ril.sensor.sleep.control=1

#Faster Boot-Animation FPS

boot.fps=20

#Tether/Hotspot Tweak

ro.tether.denied=false

#Enable Quick Power-On Mode To Reduce Boot-Time

ro.config.hw_quickpoweron=true

persist.sys.shutdown.mode=hibernate

#Disable Scrolling Cache For Faster Scrolling

persist.sys.scrollingcache=3

ro.config.tima=0

ro.config.knox=0

ro.securestorage.knox=false

security.mdpp=None

security.mdpp.result=None

wlan.wfd.hdcp=disable

# Wireless Tweaks

net.ipv4.ip_no_pmtu_disc=0

net.ipv4.route.flush=1

net.ipv4.tcp_ecn=0

net.ipv4.tcp_fack=1

net.ipv4.tcp_mem=187000 187000 187000

net.ipv4.tcp_moderate_rcvbuf=1

net.ipv4.tcp_no_metrics_save=1

net.ipv4.tcp_rfc1337=1

net.ipv4.tcp_rmem=4096 39000 187000

net.ipv4.tcp_sack=1

net.ipv4.tcp_timestamps=1

net.ipv4.tcp_window_scaling=1

net.ipv4.tcp_wmem=4096 39000 18700

wifi.supplicant_scan_interval=220

net.ipv4.tcp_window_scaling=1

# Video Acceleration Enabled And HW debugging

video.accelerate.hw=1

debug.sf.hw=1

debug.performance.tuning=1

debug.egl.profiler=1 # Measure rendering time in adb shell dumpsys gfxinfo

debug.egl.hw=1

debug.composition.type=gpu

# GOOGLE DNS

net.dns1=8.8.8.8

net.dns2=8.8.4.4

net.rmnet0.dns1=8.8.8.8

net.rmnet0.dns2=8.8.4.4

net.ppp0.dns1=8.8.8.8

net.ppp0.dns2=8.8.4.4

net.wlan0.dns1=8.8.8.8

net.wlan0.dns2=8.8.4.4

net.eth0.dns1=8.8.8.8

net.eth0.dns2=8.8.4.4

net.gprs.dns1=8.8.8.8

net.gprs.dns2=8.8.4.4

# 3G signal and speed tweaks

ro.ril.hsxpa=3

ro.ril.gprsclass=10

ro.ril.hep=1

ro.ril.enable.dtm=1

ro.ril.hsdpa.category=12

ro.ril.enable.a53=1

ro.ril.enable.3g.prefix=1

ro.ril.htcmaskw1.bitmask=4294967295

ro.ril.htcmaskw1=14449

ro.ril.hsupa.category=7

ro.ril.hsdpa.category=10

ro.ril.enable.a52=1

ro.ril.set.mtu1472=1

persist.cust.tel.eons=1

ro.config.hw_fast_dormancy=1

persist.data_netmgrd_mtu=1482

persist.data_netmgrd_nint=8

ro.use_data_netmgrd=true

ro.ril.enable.dtm=1

ro.ril.def.agps.mode=2

ro.ril.def.agps.feature=1

ro.ril.enable.gea3=1

ro.ril.enable.fd.plmn.prefix=23402,23410,23411

# Modify MTU from 1500 to 1472 on 3G network for speeding up

ro.ril.set.mtu1472=1

# Dialing Tweaks

ro.telephony.call_ring.delay=0

ro.lge.proximity.delay=25

mot.proximity.delay=25

# Smoother video streaming and tweak media

media.stagefright.enable-player=true

media.stagefright.enable-meta=true

media.stagefright.enable-scan=true

media.stagefright.enable-http=true

media.stagefright.enable-aac=true

media.stagefright.enable-qcp=true

media.stagefright.enable-record=false

# Increase camera's photo and video recording quality

ro.media.enc.hprof.vid.fps=65

ro.media.dec.aud.wma.enabled=1

ro.media.dec.vid.wmv.enabled=1

# Better Flashlight intensity and camera-flash quality

ro.media.capture.flash=led

ro.media.capture.flashMinV=3300000

ro.media.capture.torchIntensity=40

ro.media.capture.flashIntensity=70

ro.media.capture.maxres=16m

ro.media.capture.fast.fps=4

ro.media.capture.slow.fps=120

ro.media.panorama.defres=3264x1840

ro.media.panorama.frameres=1280x720

ro.camcorder.videoModes=true

ro.media.cam.preview.fps=0

ro.media.codec_priority_for_thumb=so

# Better internet browsing & download speed

net.tcp.buffersize.default=4096,87380,256960,4096, 16384,256960

net.tcp.buffersize.wifi=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.umts=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.gprs=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.edge=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.hspa=6144,87380,524288,6144,163 84,262144

net.tcp.buffersize.lte=524288,1048576,2097152,5242 88,1048576,2097152

net.tcp.buffersize.hsdpa=6144,87380,1048576,6144,8 7380,1048576

net.tcp.buffersize.evdo_b=6144,87380,1048576,6144, 87380,1048576

# Support For IPV4 and IPV6

persist.telephony.support.ipv6=1

persist.telephony.support.ipv4=1

# Better image quality, lower performance.

persist.sys.use_dithering=1

# MMS APN retry timer set to 2 sec( if SMS/MMS couldn`t be sent, it retries after 2 instead of 5 seconds)

ro.gsm.2nd_data_retry_config=max/_retries=3, 2000, 2000, 2000

# Increase jpg quality to 100%

ro.media.enc.jpeg.quality=100

# Improves Camera & Video Results

ro.media.panorama.defres=3264x1840

ro.media.panorama.frameres=1280x720

ro.camcorder.videoModes=true

ime_extend_row_keyboard=true

ime_onehand_keyboard=true

ime_split_keyboard=true

ime_vibration_pattern=0:60

# Increase the volume steps in-call

ro.config.vc_call_steps=20

# Increase camera's photo and video recording quality

ro.media.dec.jpeg.memcap=8000000

ro.media.enc.hprof.vid.bps=8000000

ro.media.enc.hprof.vid.fps=65

ro.media.enc.jpeg.quality=100

# Misc Tweaks (enables ADB service)

persist.service.adb.enable=1

# Better call voice quality.

ro.ril.enable.amr.wideband=1

# Rendering Tweaks

debug.composition.type=gpu

debug.egl.hw=1

debug.enabletr=true

debug.overlayui.enable=1

debug.qctwa.preservebuf=1

debug.performance.tuning=1

debug.sf.hw=1

dev.pm.dyn_samplingrate=1

hw3d.force=1

ro.config.disable.hw_accel=false

ro.fb.mode=1

ro.sf.compbypass.enable=0

ro.vold.umsdirtyratio=20

persist.sys.composition.type=c2d

persist.sys.ui.hw=1

video.accelerate.hw=1

# Better Telephony Settings

ro.config.vc_call_vol_steps=20

ring.delay=0

ro.lge.proximity.delay=25

mot.proximity.delay=25

ro.mot.buttonlight.timeout=0

# Audio Tweaks

persist.audio.fluence.mode=endfire

persist.audio.hp=true

persist.audio.vr.enable=false

persist.audio.handset.mic=digital

persist.audio.lowlatency.rec=false

# Better image quality, lower performance.

persist.sys.use_dithering=1

# For SD storage insert notification sound

persist.service.mount.playsnd=0

# faster youtube?

ro.ril.hep=1

# Default Network Mode

ro.telephony.default_network=10

# System prop to select audio resampler quality

af.resampler.quality=255

# System prop to select MPQAudioPlayer by default on mpq8064

mpq.audio.decode=true

# Better Scrolling responsiveness and speed

ro.max.fling_velocity=12000

ro.min.fling_velocity=8000

ro.min_pointer_dur=1

# Miscellaneous Tweaks for performance

ro.config.hw_menu_unlockscreen=false

dalvik.vm.dexopt-flags=m=y

ro.mot.eri.losalert.delay=1000

ro.telephony.sms_segment_size=160

# Hardware 2D & 3D Rendering

hw3d.force=1

hw2d.force=1

# 3d performance

persist.android.strictmode=0

ro.secure=0

# For the default value of agps

ro.ril.def.agps.mode=2

ro.ril.def.agps.feature=1

#

ro.com.google.locationfeatures=1

ro.com.google.networklocation=1

htc.audio.alt.enable=0

htc.audio.hac.enable=0

# Other Tweaks

qemu.hw.mainkeys=1

ro.config.hw_new_wifitopdp=1

vm.dirty_ratio=90

vm.dirty_background_ratio=70

vm.vfs_cache_pressure=10

vm.min_free_kbytes=4096

ro.config.hw_new_wifitopdp=1

Minimum brightness of your screen

ro.lcd_min_brightness=20

#

ro.ril.gprsclass=10

# Saves some battery without reducing performances

wifi.supplicant_scan_interval=220

power.saving.mode=1

ro.vold.umsdirtyratio=20

proximity_incall=enable

ro.config.hw_quickpoweron=true

usb_wakeup=enable

ro.config.hw_power_saving=true

#

debug.sf.hw=1

video.accelerate.hw=1

persist.sys.use_dithering=1

# System Tweaks

ro.HOME_APP_ADJ=1

ro.mot.eri.losalert.delay=1000

ro.config.hw_fast_dormancy=1

ro.ril.enable.amr.wideband=1

ro.config.hw_fast_dormancy=1

ro.config.hw_quickpoweron=true

# Miscellaneous Tweaks

persist.sys.NV_FPSLIMIT=90

debug.qctwa.statusbar=1

debug.qctwa.preservebuf=1

debug.qc.hardware=true

com.qc.hardware=true

ro.telephony.sms_segment_size=160

ro.config.hw_fast_dormancy=1

persist.sys.shutdown.mode=hibernate

ro.config.hw_power_saving=true

ro.media.enc.hprof.vid.fps=65

ro.mot.buttonlight.timeout=0

ro.ril.set.mtu1472=1

touch.presure.scale=0.001

# Disables data sent and logging

ro.config.nocheckin=1

profiler.force_disable_err_rpt=1

profiler.force_disable_ulog=1

# Scrolling Responsiveness

windowsmgr.max_events_per_sec=300

persist.cust.tel.eons=1

# Power Saving Tweaks

pm.sleep_mode=1

# DalvikVM

dalvik.vm.verify-bytecode=false

dalvik.vm.execution-mode=int:fast

dalvik.vm.checkjni=false

dalvik.vm.dexopt-data-only=1

dalvik.vm.heapstartsize=1m

dalvik.vm.heapgrowthlimit=64m

dalvik.vm.heapsize=128m

dalvik.vm.verify-bytecode=false

dalvik.vm.execution-mode=int:jit

dalvik.vm.lockprof.threshold=250

dalvik.vm.dexopt-flags=m=y

dalvik.vm.jmiopts=forcecopy

# Performance

debug.composition.type=gpu

ro.max.fling_velocity=20000

ro.min.fling_velocity=18000

debug.performance.tuning=1

debug.kill_allocating_task=0

debug.overlayui.enable=1

debug.egl.profiler=1

debug.egl.hw=1

debug.sf.hw=1

hw3d.force=1

hw2d.force=1

force_hw_ui=true

persist.sys.purgeable_assets=1

persist.sys.use_dithering=1

ro.min_pointer_dur=1

debug.kill_allocating_task=0

persist.sys.ui.hw=1

ro.debuggable=1

ro.config.disable.hw_accel=false

ro.kernel.android.checkjni=0

ro.secure=0

ro.min_pointer_dur=1

# Saves some battery without reducing performances

wifi.supplicant_scan_interval=220

power.saving.mode=1

ro.vold.umsdirtyratio=20

proximity_incall=enable

ro.config.hw_quickpoweron=true

usb_wakeup=enable

ro.config.hw_power_saving=true

# Battery save

ro.ril.disable.power.collapse=0

ro.ril.power_collapse=1

power_supply.wakeup=enable

ro.mot.eri.losalert.delay=1000

ro.config.hw_fast_dormancy=1

ro.config.hw_power_saving=1

pm.sleep_mode=1

ro.ril.disable.power.collapse=0

debug.performance.tuning=1

debug.composition.type=hw

debug.sf.hw=1

profiler.force_disable_ulog=true

profiler.force_disable_err_rpt=true

profiler.force_disable_err_rpt=1

profiler.force_disable_ulog=1

ro.vold.umsdirtyratio=20

dalvik.vm.checkjni=false

dalvik.vm.execution-mode=int:jit

video.accelerate.hw=1

power_supply.wakeup=enable

# Increase some Performance

ro.secure=0

persist.sys.use_16bpp_alpha=1

ro.product.gpu.driver=1

ro.min.fling_velocity=8000

debug.gr.swapinterval=1

debug.kill_allocating_task=0

ENFORCE_PROCESS_LIMIT=false

hw3d.force=1

ro.debuggable=1

ro.min_pointer_dur=1

ro.min_pointer_dur=1

ro.wmt.blcr.enable=0

# 16bit Transparency

persist.sys.use_16bpp_alpha=1

# Screen recognizes only two fingers

ro.product.multi_touch_enabled=true

ro.product.max_num_touch=2

# Remove FPS cap

debug.gr.swapinterval=0

# Qualcomm tweaks

com.qc.hardware=1

debug.qc.hardware=true

debug.qctwa.preservebuf=1

debug.qctwa.statusbar=1

# Enables MTP mode

persist.sys.usb.config=mtp

#For usb storage

ro.usb_host=1

#Simulate sdcard on /data/media

persist.fuse_sdcard=true

ro.storage_structure: define the storage structure of this project

# FUSE: 0x8, FAT: 0x4, SD: 0x2, INS: 0x1

# Example: If the project has FUSE with SD card, the value should be defined as 10 (dec)

ro.storage_structure=10

#Disable USB Debugging Popup

persist.adb.notify=0

# Bass audio props for Lolipop

tunnel.decode=false

lpa.use-stagefright=false

persist.sys.media.use-awesome=1

sys.keep_app_1=com.bel.android.dspmanager

ro.audio.samplerate=48000

ro.audio.pcm.samplerate=48000

af.resampler.quality=255

af.resample=52000

# Game tweaks

persist.sys.NV_FPSLIMIT=60

persist.sys.NV_POWERMODE=1

persist.sys.NV_PROFVER=15

persist.sys.NV_STEREOCTRL=0

persist.sys.NV_STEREOSEPCHG=0

persist.sys.NV_STEREOSEP=20

persist.sys.purgeable_assets=1

# Enable Quick Power-On mode to reduce boot-time

ro.config.hw_quickpoweron=true

# ButtonLight Always On - Remove # Below To Enable

ro.mot.buttonlight.timeout=0

# Enables 270 Degree Rotation

windowsmgr.support_rotation_270=true

Multi users

# Multi Users

fw.max_users=30

fw.show_multiuserui=1

This one also resolved the issue of poor signal and may correct the volte signal and boost up network..because when i am using j2 i also get very bad signal..even signal strength is gud..i applied these values in build.prop...I Get good signal best volte boost up network..apply and tell mee....