Tait TM8100 mobiles - Page 268

268 Transmitter Fault Finding (>25W) TM8100/TM8200 Service Manual
© Tait Electronics Limited November 2007
Frequency Bands
Where test procedures or figures differ according to the frequency band of
the radio, the frequency band is given in brackets. The frequency band may
be referred to as either ‘VHF’ (very high frequency) or ‘UHF’ (ultra high
frequency) or identified by the frequency sub-band, such as ‘B1’ or ‘H7’.
For example:
In some cases, differences in performance across a wide band of frequencies
within a frequency band may mean that different figures are given for
specific frequencies. For example:
A definition of frequency bands is given in “Defining Frequency Bands” on
page 131.
Some fault-diagnosis tasks require programming the radio with the lowest,
centre or highest frequency in the radio’s frequency band. The relevant
frequencies for the different bands are listed in Table 11.2.
Table 11.1 CCTM commands required for the diagnosis of faults in the transmitter
Command Description
32 Set radio in receive mode
33 Set radio in transmit mode
47 Read temperature near PAs — displays temperature x in degrees celsius and voltage y
101 x y 0 Set transmit frequency (x in hertz) and receive frequency (y in hertz) to specified values
114 x Set DAC value x (in range 0 to 1023) of transmit power
304 Read clamp current at gate of PA driver — displays DAC value x (in range 0 to 255)
304 x Set DAC value x (in range 0 to 255) of clamp current at gate of PA driver
318 Read forward-power level — displays corresponding voltage x in millivolts
319 Read reverse-power level — displays corresponding voltage x in millivolts
326 x Set transmitter power level x (0=off, 1=very low, 2=low, 3=medium, 4=high, 5=maximum)
331 Read bias voltage for first PA — displays DAC value x (in range 0 to 255)
331 x Set DAC value x (in range 0 to 255) of bias voltage for first PA
332 Read bias voltage for second PA — displays DAC value x (in range 0 to 255)
332 x Set DAC value x (in range 0 to 255) of bias voltage for second PA
334 x Set synthesizer on (x=1) or off (x=0) via DIG SYN EN line
335 x Set transmit-receive switch on (x=1) or off (x=0) via DIG SYN TR SW line
RF output power: > 60W (VHF), > 52W (UHF)
current: < 15A (VHF), < 12A (UHF)
RF output power: > 60W (VHF), > 52W (UHF), > 40W (700MHz),
>45W(800MHz)