Arcam rCube Service Manual page 6

RF AMP
continue
The RF stage is both Receive or Transmit (transceiver) allowing Cubes to be linked for docked
iPod source and external analogue inputs hence you will see two spate paths that are switched
R.F switches seen as IC701 IC702 IC703 two separate Antenna are used and the rCube has the
ability to select the most stable aerial at any given time the audio path into/out of the Kleer
chip is seen as KL3012 regardless of status – when in receive mode the RF power amp is
bypassed by IC701, IC702 in transmission mode both switches are toggled to bring the Saw
filter FL700 and Low RF Pass filter FL701 with Power Amp IC704 back in line, The two antenna
are connected to the surface mount sockets at SKT700 an SKT701.
DAC Filters and Amplifiers
Audio arrive the DAC filters and Amplifiers circuit from the DSP as 4 separate channels these
being TWEET_L/ TWEET_R/ WOOF_L/ WOOF_R each channel travel thru an identical filter
circuit TWEET_L channel will be described.
TWEET_R audio arrive at capacitor C508 before traveling into the filter based around the
NJM2114 at location IC500 the audio is further filtered by the network of capacitors based
around C326 and C327 in combination with C510 – audio then passes into the Volume control
IC at location IC501 on pin 1 and can be seen to exit (volume adjusted) on pin 14 – the volume
control is under control of the main micro at position U302 via line VOL_CLK / VOL_DAT the line
will know be known as TWEET_VOL_R and travels into the Power amp chip at location IC507
(shared with TWEET_VOL_L) this package is driven from the +19v_amp supply and is thermally
protect to trigger at 100c / standby and mute control comes from the main micro and temp
status of the power amp can be reported to back to the micro.
The WOOF_VOL_L and WOOF_VOL_R audio paths use a bridged power amp each seen at
locations IC504 and IC05.
Display and keyboard
The display board is connected to the main board via the iPod header board and it's primary
link on the main board is main micro U301.
The board is built around the IC1 a AT42QT1060 6‐channel sensor IC this allows for capacitive
sensors as keys and also perform the role of driving the top plate LED's with exception of
Standby LED status red (this comes directly from U301) the chip is supplied by the 3V14 STBY
power supply, the reset circuit shown on the circuit was not required by the final design.
All LEDs are driven from the +5_DIS rail apart from standby (red) as this is on the 3V14(STBY)
rail.