Table of Contents
maintenance
bugs
interferences
missing high pass filter
backlight
onboard antenna
power supply
external clock input
isp pin floating
reset pin
maintainence
broken display
no audio input/output
bad power switch
working, but no data
display flickering
data transfer takes very long
rgb leds
antenna connector
Bias-T
protection
performance improvements
PLL
interferences
maintenance
transcribed from
rad1o++ talk at 32c3
, referencing
the slides
starting at page 38
bugs
interferences
sample clocks are at 2 and 20MHz
doubled at 4 and 40MHz
⇒ interference spikes at 80, 120, 160, 200,
goes away at 400MHz
missing high pass filter
unpopulated in big rf area (FL301)
RX/TX over 2.75GHz not possible
solution 1:
when only RX: just bridge it
solution 2:
populate it yourself
backlight
on some rad1os the backlight might stay on and drain battery
⇒ unplug battery
onboard antenna
should be at 2.48GHz-2.5GHz
measured at 2.35GHz
power supply
1st usb port always used to suck power (up to 700mA for TX)
2nd usb port is limited to 475mA
solution 1: patch hackrf to use 2nd port for data
solition 2: build usb cable with seperate power connector
external clock input
clock input is wired to ground, connection below chip
solution: solder it on the pad of the crystal and supply with 27MHz
isp pin floating
under battery an isp header can be soldered on
one of the pins should be pulled high, but isnt (see page 52)
if it is low, the rad1o wont boot
reset pin
connecting anything to that pin will trigger reset
12k pull-up is already there, but it's still touchy
maintainence
broken display
replace with one from a Nokia 6100
no audio input/output
check audio connector solder joints
move plug around a little bit
bad power switch
remove it
put a jumper on there
working, but no data
check with other/shorter usb cable
display flickering
charge battery
data transfer takes very long
yea it's just slow flash
wait
use “safe eject”/sync
rgb leds
resistors populated incorrectly/unpopulated
bug documented incorrectly
just bridge at 3 places (see page 60 and
RGB LEDs
)
antenna connector
when soldering on an antenna
dont bridge left 2 big pads
they are very close together
would bridge power supply
Bias-T
to power an antenna through hackrf software
put “large” inductor (“like 10μH”) onto the smaller pads below the SMA pads (see page 62) (dont bridge with antenna pads)
if your antenna has an DC path, it might burn out the inductor (see page 63)
protection
display and some inductors (especially rf area) are very fragile
shield it
put a case on it
performance improvements
PLL
code improved to for better performance <2.15GHz
just upgrade your f1rmware
interferences
10MHz reference output disabled in software (because most people wont use it anyway)
transceiver and PLL are now both at 40MHz
⇒ no extra spurs caused by 50MHz PLL clock
just upgrade your f1rmware