Nokia 8280 Service Manual 7 rh10trouble
CCS Technical Documentation
RH-10 Series Transceivers
Troubleshooting
Issue 1 09/2002 Confidential Nokia Corporation
RH-10
Troubleshooting CCS Technical Documentation
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CCS Technical Documentation Troubleshooting
Contents
Page No
Transmitter Troubleshooting.......................................................................................... 5
Tuning Information........................................................................................................ 5
ST Batman VHFPLL ...................................................................................................5
ST TX Detector Cell ....................................................................................................5
ST Robin VHFPLL Cell ..............................................................................................6
SN Cell PA Temp ........................................................................................................6
SN Cell RX BB Filter ..................................................................................................7
SN Cell RX DC Offset I (or Q) ...................................................................................7
SN AMPS RX BB Filter ..............................................................................................7
SN AMPS RX DC Offset I (or Q) ...............................................................................7
Test TX Start-up Current .............................................................................................8
Test TX Start-up Amplitude ........................................................................................8
TN VCTCXO Frequency .............................................................................................8
TN TX DC Offset Reference Power ..........................................................................10
TN TX DC Offset Carrier Suppression .....................................................................11
TN TX IF AGC Cell Po (O) [or (1), (2), (3), or (4)] .................................................11
TN PA Gain Cal Cell Po (0) [or, (1), (2), (3), (4), or (5)] .........................................12
TX TX IF 11 dBm Set CELL Po ...............................................................................13
TN TX RF AGC Cell Po (0) [or (1), or (2)] ..............................................................14
TN TX Gain Comp Cell Po MD (or LO, LM, ML, MH, HM, or HI) .......................14
TX IF 11 dBm Set CELL Po .....................................................................................15
TN TX RF AGC Cell Po (0) [or (1), or (2)] ..............................................................15
TN TX Gain Comp Cell (or PCS) Po MD (or LO, LM, ML, MH, HM, or HI) ........16
TN G_Offset Cell MD ...............................................................................................17
TN AMPS PL2 Po Mid (or Low, LowMid, MidLow, MidHigh, HighMid, or High) 17
TN AMPS PL3 (or 4, 5, 6, or 7) Po ...........................................................................18
TN TX Limiting Po Cell IS95, Low channel (or LowMid, MidLow, Mid, MidHigh,
HighMid, or High channel) ......................................................................................18
TN TX Limiting Cell CDMA2000: Po ......................................................................19
TS ACPR Cell — Low ..............................................................................................19
TN RX IF AGC RXdBCtr (0) [or (1) or (2)] .............................................................19
TN LNA AMPS (or Cell) LowGain (or HighGain) LO (or LM, ML, MD, MH, HM,
HI) ............................................................................................................................20
Final UI Test: Rho .....................................................................................................20
Final UI Test: Frame Error Rate (FER) .....................................................................20
Final UI Test: SINAD ................................................................................................20
Probing/Troubleshooting ............................................................................................. 21
Overview ....................................................................................................................21
Probing Tables ...........................................................................................................22
Probing Diagrams ......................................................................................................29
Phoenix Instructions ..................................................................................................30
Turning on Cell CDMA Transmitter....................................................................... 30
Turning on AMPS Transmitter ............................................................................... 31
Turning on Receiver Only....................................................................................... 32
Verifying a Single Manual Tuning.......................................................................... 33
Adjusting PDM Values for AGCs and AFC........................................................... 33
Reading Tuning Values from the Phone................................................................. 34
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Reading RSSI and AGC PDM Values from the Phone .......................................... 34
Loading PRLs into the Phone.................................................................................. 35
Changing Between Local Mode and Normal Mode................................................ 35
Baseband Test Tone for AMPS Transmitter Tests.................................................. 36
Block Diagrams .........................................................................................................37
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Transmitter Troubleshooting
The Diva troubleshooting section includes tuning information, troubleshooting test,
probing points, and block diagrams.
Tuning Information
ST Batman VHFPLL
This is one of the phone’s self-tests, which gives either a Pass or Fail result only.
The VHFPLL is inside the Batman IC. The phone checks the VHFPLL’s lock detect bit. If this
bit indicates that the PLL is unlocked, the test will fail.
Manual Verification: Turn on the Cell or PCS receiver to any channel and probe at L701
(probing point 39 in Figure 2), using an RF probe connected to a spectrum analyzer tuned
to 256.2 MHz. If the PLL is locked, it will be stable in frequency. If it is unlocked, you may
have to use a wide span to see it since it may be far off frequency.
Troubleshooting: Check C701, C714, R703, R702, C715, R704, V701, C716, L701, and
C702. Check power supplies to Batman, particularly check for 2.7v on VR5 at C710 and
on VR7 at C708. Check for 1.8v on VIO. If no fault is found, replace N701 (Batman).
ST TX Detector Cell
This is one of the phone’s self-tests, which gives either a Pass or Fail result only.
The phone transmits at several power levels and checks the ADC value of the power
detector. The ADC value is measured first for a set of AGC values, and then each AGC
value is changed individually to ensure that the ADC changes as each AGC change is
made.
Manual Verification: Using Main Mode, turn on the Cell CDMA TX with the channel set to
384 and turn on IS95 modulation using CDMA control. Using the PDM window, set:
TX_IF_AGC to -100
TX_RF_AGC to -512
PA_AGC to +511
Record the TX signal power from the antenna connector, using a spectrum analyzer centered at 836.52 MHz. (The self-test measures the power detector reading instead, but at
the present time it cannot be done with Phoenix. An easy way to check functionality
without removing the covers is to check transmitted power.) Transmitter power should be
greater than 24 dBm. (PWR_OUT greater than 1.91v, which corresponds to the power
detector ADC=700.)
For each of the next three cases, TX power should be less than 24 dBm (less than 1.91v
on PWR_OUT).
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1 TX_IF_AGC to -80
TX_RF_AGC to -512
PA_AGC to -512
2 TX_IF_AGC to +511
TX_RF_AGC to -512
PA_AGC to +511
3 TX_IF_AGC to -80
TX_RF_AGC to +511
PA_AGC to +511
Troubleshooting: If there is a failure associated with only some of the cases above, check
the AGC voltages and components of the associated PDMs as described in Tables 1 and 4.
For problems with the IF or RF AGC, also check Robin and supporting components. For PA
AGC problems, also check the PA and supporting components. If all the above cases fail,
troubleshoot the TX chain as described in this section.
If all the output powers pass, perhaps the test is failing because the ADC voltage is
wrong. The limit is 1.64v. If the voltages are wrong, then check the power detector at
R821, R801, R804, L801, C805, R806, R805, C803, V801, C804, and C807, and also Robin.
If the voltages are correct and it still fails, check the UEM (D200).
ST Robin VHFPLL Cell
This is one of the phone’s self-tests, which gives either a Pass or Fail result only.
The VHFPLL is inside the Robin IC. The phone checks the VHFPLL’s lock-detect bit. If this
bit indicates that the PLL is unlocked, the test will fail.
Manual Verification: Turn on the Cell CDMA receiver to any channel and probe at L611
(probing point 11, Figure 1), using an RF probe connected to a spectrum analyzer tuned
to 346.2 MHz. If the PLL is locked, it will be stable in frequency. If it is unlocked, you may
have to use a wide space to see it since it may be far off frequency.
Troubleshooting: Check C612, C613, R607, R605, C632, R606, C638, L611, C631, C630,
V601, C629, V602, C637, R609, C618. Check power supplies to N601 (Robin), ensuring
2.7v on VR3 and VR6, and 1.8v on VIO. If no problems are found, replace Robin.
SN Cell PA Temp
This is one of the phone’s self-tunings, which reads the ADC voltage of thermistor R808,
and checks to make sure the phone is at room temperature. A phone should not be tuned
while it is either hot or cold.
The phone reports the ADC voltage value of the thermistor and it should be within the
set limits.
Manual Verification: Ensure the phone is cool by letting it cool down for several minutes.
Retest, keeping in mind that if there is a short circuit on the board, the phone will get
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hot very quickly.
Troubleshooting: If the phone was recently transmitting in Cell band at full power for an
extended period of time, it is probably hot for that reason. Let it cool down for a few
minutes before proceeding. If it still fails, there may be either a short on the board or a
problem with the PA Temp circuitry. To check PA Temp circuitry, check R808, C232, R202,
and D200. If a short is suspected, check the Cell PA first. If an infrared camera is available, this is one of the easiest methods to detect a short.
SN Cell RX BB Filter
This is one of the phone’s self-tunings, which tunes the lowpass filter in the Batman IC
(N701), in Cell CDMA mode.
This self-tuning returns one of the filters tuned parameters, which should be within the
set limits.
Manual Verification: Use “RF Tuning” dialog box in Phoenix; set mode to Self Tune, and
choose this tuning.
Troubleshooting: Check Batman (N701) and supporting components.
SN Cell RX DC Offset I (or Q)
This is one of the phone’s self-tunings, which measures and adjusts the cell band CDMA
receiver DC offsets until they are within the set limits.
The DC offset is returned for I (or Q).
Manual Verification: Use “RF Tuning” dialog box in Phoenix; set mode to Self Tune, and
choose this tuning.
Troubleshooting: Check Batman (N701) and supporting components.
SN AMPS RX BB Filter
This is one of the phone’s self-tunings, which tunes the lowpass filter in the Batman IC
(N701), in AMPS mode.
This self-tuning returns one of the filters tuned parameters, which should be within the
set limits.
Manual Verification: Use the “RF Tuning” dialog box in Phoenix; set mode to Self Tune,
and choose this tuning.
Troubleshooting: Check Batman (N701) and supporting components.
SN AMPS RX DC Offset I (or Q)
This is one of the phone’s self-tunings, which measures and adjusts the cell band CDMA
receiver DC offsets until they are within the set limits.
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The DC offset is returned for I (or Q).
Manual Verification: Using the “RF Tuning” dialog box in Phoenix, set mode to Self Tune,
and choose this tuning.
Troubleshooting: Check Batman (N701) and supporting components.
Test TX Start-up Current
This test turns on the AMPS transmitter (PCS transmitter for PCS-only phones) and measures current of the whole phone—which can detect some assembly errors.
Manual Verification: Set the phone to local mode and turn on the AMPS transmitter. Set
the PDM values as listed in Table 1a for AMPS Power Level 5 (for PCS, set output power
to +12dBm). Read the phone’s current on the power supply and check to see that it is
within the set limits. If the power supply does not display current draw, use a current
meter in series with the phone. If the phone powers down when the mode is set, it may
be that the phone is drawing more current than the current limit setting on the power
supply.
Troubleshooting: If current is very high, there may be a short circuit on the phone caused
by a solder bridge, a failed component that is internally shorted, a component placed
with the wrong rotation, or some other reason. Short circuits can be difficult to find, but
one of the easiest methods is to use a thermal camera and look for hot spots that are not
normally hot. Look for the hottests spots. A visual inspection can find solder bridges or
wrong component rotations. A failed component can be found by functional tests of the
phone’s sub-blocks.
Test TX Start-up Amplitude
This test turns on the AMPS transmitter and checks for the presence of a TX signal with
an amplitude within a specified range. A wide range is allowed since the transmitter is
not yet tuned.
Manual Verification: Set the phone to local mode and turn on the AMPS transmitter set
to channel 384. Set the AGC PDM values as in Test 17. Look for an output signal at
836.52 MHz with an amplitude within the set limits. The frequency of the signal may not
be accurate since the VCTCXO has not been tuned yet.
Troubleshooting: Check proper placement, rotation, and soldering of the components of
the TX chain, as shown in Figure 1. Check for the presence of LO tones as listed in
Table 2. Check for the presence of a TX signal at each point in the TX chain, probing
according to Table 2.
TN VCTCXO Frequency
The purpose of this tuning is to determine what the AFC DAC value needs to be in order
to center the VCTCXO frequency. The PCS transmitter is turned on and no TX baseband
modulation is provided. The carrier then is centered in frequency. This is done to the carrier after it has been mixed up to 1880 MHz, since it is easier to measure the tolerance of
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1 ppm at 1880 MHz than it is at 19.2 MHz. Additionally, the tone at 1880 MHz can be
measured without taking the phone apart.
The result of this test is a PDM value for the AFC DAC, which must be within +/- 150,
corresponding to 2.2v on the VCTCXO control pin (pin 1) and the carrier centerd within
+/- 100Hz. The VCTCXO must be able to be centered within a certain voltage range in
order to allow for aging of the crystal (the centering voltage slowly drifts over time and
the phone will eventually run out of voltage range if it begins too close to the edge of
the range).
Manual Verification: Using the “RF Main Mode” dialog box in Phoenix, turn on the PCS
transmitter and set it to channel 600. Do not add any modulation. Using the RF Tuning
window, set Mode=RF Tuning, and choose this tuning. Look for a transmitted tone on the
spectrum analyzer at 1880 MHz. If no tone is present, proceed to Troubleshooting below.
Center the carrier to within +/- 100 Hz of 1880 MHz. (If sidetones are present, be careful
to center the carrier and not one of the sidetones.) The values you enter into the Values
edit box are the AFC values that control the VCTCXO frequency. Start with a value of “0”,
adjusting until it is centered, staying within the set limits.
Troubleshooting:
1 If there is no tone, probe pin 3 of G501 for a tone at 19.2 MHz. If this is not
present, check power supplies, particularly ensuring 2.7v on VCTCXO Vcc pin,
pin 4 of G501. Also check the control pin (pin 1 of G501) for a voltage between
0.4 and 2.7v. If the voltages are correct, and soldering of all G501 terminals is
correct, replace G501. If 19.2 MHz tone is present but tone at 836.52 MHz is not,
troubleshoot Cell TX Chain section.
2 If the carrier is present but the PDM needed to center it is outside of the +/- 150
range, or if it cannot be centered, there is a hardware problem.
3 In the following procedure, performing frequency centering on the RF carrier at
1880 MHz will detect frequency errors due to the VCTCXO and supporting hardware, which will be the majority of the problems, but will not detect frequency
errors due to the hardware that mixes the VCTCXO tone at 19.2 MHz up to
1880 MHz. In order to also troubleshoot this hardware, frequency centering
should be performed on the 19.2 MHz tone to +/- 19.2 Hz on pin 3 of G501,
using a frequency counter. Then the VHF and UHF LOs should be checked. (Since
this will be time-consuming and will probably only account for a small percentage
of the failures, it is not recommended unless the situation justifies the time spent.)
The VHF LO is inside the Robin IC (N601) and troubleshooting of the Cell UHF LO
is according to Table 2.
4 If the carrier can be centered, but the PDM is out-of-range, check the control
voltage on pin 1 of G501. If it is 2.2v (and pin 4 is at 2.7v and pin2 at 0v), then
the VCTCXO (G501) is working correctly but the circuit that delivers the control
voltage is not. Check soldering of all G501 terminals; also check R510, R511,
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C503, and D200. If the control voltage on pin 1 of G501 is not 2.2v, but the carrier is centered, then there is a problem with the VCTCXO G501. If there is 2.7v on
pin 4 and the soldering is correct, then replace G501.
5 If the carrier cannot be centered, check to see if you can adjust to 2.2v on pin 1
of G501. If you can, within the PDM range of +/- 150, then the circuitry that
delivers the voltage is working correctly, and the VCTCXO has a problem. Troubleshoot as described in the previous section. If you cannot adjust to 2.2v within the
accepted range, then the AFC circuitry has a problem. Troubleshoot it as
described in the previous section.
6 If there is a fault with both the AFC circuitry and the VCTCXO, then several com-
binations of the previously described conditions are possible. Start by ensuring
2.2v on pin 1 of G501, using a PDM within the range of +/- 150. Then center the
phone.
TN TX DC Offset Reference Power
Both this tuning and the next (TN TX DC Offset Carrier Suppression) are to adjust the
DC offset voltages on the I and Q inputs to the modulator for minimal carrier
feedthrough (maximum carrier suppression). Initially, the DC offsets are set to a nominal
value, and the power of a tone offset in frequency 20 kHz from the carrier is measured in
dBm and recorded as a reference (in this tuning). Then, in the next tuning, the carrier
suppression (delta between center tone and tone that is offset 20 kHz) is measured. If it
passes, it is reported in that tuning. If not, the DC offsets are adjusted until it passes, and
the passing value is reported.
The reported result is the power in dBm of the tone that is offset 20 kHz from the carrier,
as measured on the antenna connector, with the nominal DC offsets applied.
Manual Verification: In Phoenix, use the RF Main Mode dialog box to set the AMPS
transmitter to channel 384. Using the RF Tuning dialog box, set the I and Q DC offsets to
0,0 by entering 0,0 in the Values edit box. Center the transmit signal on the spectrum
analyzer, set the span to 100 kHz. Lower the bandwidth so that the two sidetones can be
differentiated from the carrier. Measure the amplitude of the sidetone at 20 kHz above
the carrier. The amplitude of the sidetone will probably be higher than that of the carrier.
The amplitude should be within the test limits.
Troubleshooting: If the carrier is not present, troubleshoot the cell TX chain using the
“things to check” list and probing table/diagrams. If the two tones offset at 20 kHz are
not present, check for them with an oscilloscope on one of the four pads of probing
point 1 in Figure 1, being very careful not to short the pad to an adjacent pad. The frequency should be 20 kHz. If tone is not present on these four pads, then there is a problem with D200 (UEM). If the tones are present at probing point 1 but not on the TX
signal, check to see if they are on Robin output at L613 at 836.52 MHz + 20 kHz. If not,
there is a problem with N601 (Robin). Ensure power supplies to Robin (VR2, VR3, VR6,
and VIO) are correct. Check components around Robin. If still failing, replace Robin.
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TN TX DC Offset Carrier Suppression
(See TN TX DC Offset Reference Power) tuning section. This step reports the delta
between the reference at 836.52 + 20 kHz and the minimum carrier level at 836.52 MHz.
The result is a delta in dB between the reference at 836.52 MHz + 20 kHz and the minimum carrier level at 836.52 MHz found by adjusting the DC offsets for I and Q individually. The delta should be at least 35 dB.
Manual Verification: Set up the phone as in the previous test, and record the reference
power of the offset tone. Measure the delta between the center and offset tones. If the
delta is 35 dB or greater, the phone passes. If less than 35 dB, vary the “I” DC offset on
the “Values” line in the RF Tuning dialog box, using the values listed below until the minimum carrier maximum delta is found. Leave Q at 0. On the “Values” line, enter “I,Q”. The
appropriate values (in decimal) are:
-560
-504
-448
-392
-336
-280
-224
-168
-112
-56
0
56
11 2
168
224
280
336
302
448
504
560
If the minimum is 35 dB or greater, the phone passes. If the minimum is less than 35 dB,
then vary Q in the same manner as I, using the above values, holding I constant at the
minumum value determined above, until the delta is at least 35 dB.
Troubleshooting: Check N601 (Robin), D200 (UEM), and associated components.
TN TX IF AGC Cell Po (O) [or (1), (2), (3), or (4)]
The IF gain curve is characterized by varying the TX_IF_AGC and measuring the transmit
power. This is only done once (in cell CDMA mode) since the same circuitry is used for
both cell.
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The results are TX power readings in dBm of the transmitted signal corresponding to
given PDM settings of the Cell TX IF AGC.
Manual Verification: Set the phone in local mode; then program it to Cell CDMA RX/TX
mode on channel 384. Set modulation to IS95 voice. Set the Cell PA PDM to +218 decimal and the TX RF AGC to -512 decimal, using the sliders in the PDM dialog box under
the RF drop-down menu. Change the TX_IF_AGC to the settings in the following table
and measure the TX power levels, checking to see that they are within the specified
range.
PDM for TX IF AGC Acceptable range for output power (in dBm)
(a) +300 decimal check tuning
(b) +150 results file
(c) 0 for limits
Change the TX_RF_AGC PDM to +511. Leave the TX_IF_AGC at 0 and the PA_AGC at
+218. Measure the output power. Subtract this power from the power measured in (c)
above. This is the RF_AGC gain delta.
Leave the PA_AGC and TX_RF_AGC values as is; then enter the alues listed below for the
TX_IF_AGC. Measure the output power, then add to each the RF_AGC gain delta calculated above. Check that these sums are within the listed ranges.
PDM for TX IF AGC
-200 check tuning results
-400 file for limits
Acceptable range for sum:[output power +
RF_AGC gain delta], in dBm
Troubleshooting: Check Robin (N801) and supporting components. Also check D400,
which generates the PDM signals. Check AGC PDM voltages according to Tables 1 and 4.
Troubleshoot the rest of the transmitter chain, if necessary.
TN PA Gain Cal Cell Po (0) [or, (1), (2), (3), (4), or (5)]
These tunings model the cell PA gain curve by setting the PA AGC PDM to several values
and measuring output power. First, the TX PA AGC and the TX RF AGC are set to (approximately) their maximum used values (not the maximum possible values, but the maximum of the range over which they are used). Then, the TX IF AGC is set so that the
transmit power on the antenna connector is approximately +11 dBm (this power is
reported in the next tuning, TX TX IF 11 dBm Set CELL Po). Then, six PDM values are
written to the PA AGC and the output power is measured for each. These values are
reported in this tuning. The software then performs curve fitting to interpolate between
the measured data points.
The result is the transmitted power in dBm for each of the six PA AGC PDM settings
(results labeled 0 through 5).
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Manual Verification: Turn on the cell CDMA transmitter in Phoenix, using the RF Main
Mode dialog box, and set it to channel 384. Set modulation to IS95 voice.
Set the TX_IF_AGC PDM to 0 decimal.
Set the PA AGC PDM to +218 decimal.
Set the TX RF AGC PDM to -512 decimal.
Adjust the TX IF AGC PDM so that the transmitted tone at 836.52 MHz measures
+11 dBm +/- 0.5 dB on the antenna connector, using a spectrum analyzer (use 0 as a
starting point).
Note the value obtained in the step above as it will be needed in other Troubleshooting sections.
Write the PDM values listed in the following table into the PA AGC and record the output
power. Check to see if the output power is within the ranges listed on the tuning result
printout. (Limits are not provided in this document as they may change.)
PDM for PA AGC Acceptable range for output power (in dBm)
+218 decimal limit range for Po(5)
-12 limit range for Po(4)
-202 limit range for Po(3)
-268 limit range for Po(2)
-329 limit range for Po(1)
-366 limit range for Po(0)
Troubleshooting: If the power readings are low, check the AGC voltages as given in
Tables 1 and 4. You can also probe on the PA input as given in Table 2 to find out if the
power level is going into the PA, or if the power level is correct going into the PA but the
PA gain is too low. If the power level going into the PA is too low, probe the TX chain at
all the other points prior to the PA listed in the table to see where the gain is lacking.
When that point is identified, check the soldering of all related components, and replace
components until the fault is found. If the power on the PA input is not low and the PA
AGC voltage is correct, similarly probe the power at all points after the PA to find the
fault—being extremely careful not to short the probing point to ground because this will
instantly destroy the PA. Visually check soldering first, and probe on PA output as a last
resort.
TX TX IF 11 dBm Set CELL Po
See previous tuning (TN PA Gain Cal Cell Po (0) [or, (1), (2), (3), (4), or (5)]). This is
the part of the previous tuning when the TX IF AGC is adjusted so that the output power
is +11 dBm.
The result is a power in dBm. A perfect result would be +11.00 dBm.
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Manual Verification: See previous section.
Troubleshooting: See previous section.
TN TX RF AGC Cell Po (0) [or (1), or (2)]
This tuning characterizes the RF AGC curve by entering PDM values to the RF AGC and
measuring the output power.
The results are TX power readings in dBm of the transmitted signal measured for each of
the listed PDM settings of the Cell TX RF AGC.
Manual Verification: Set up the transmitter as described in tuning 24.3 above.
Set the Cell PA PDM to -329.
Set the TX_IF_AGC to the value determined in tuning 24.3 above to give +11 dBm on the
output.
Change the TX RF AGC to the settings in the following table, and measure the TX power
levels. Check to see that they are within the specified range.
PDM for TX RF AGC Acceptable range for output power, in dBm
-512 decimal check
-67 decimal limits
-22 decimal in tuning
+418 results
+511 file
Troubleshooting: Check Robin (N801) according to Tables 1, 2, and 4. Also check D400,
which generates the PDM signals. Check AGC PDM voltages according to Table 1. Troubleshoot the rest of the cell transmitter, if needed.
TN TX Gain Comp Cell Po MD (or LO, LM, ML, MH, HM, or HI)
Both this tuning and the next (TX IF dBm Set Cell Po) ensure that the value of TxdBCtr
correctly corresponds to the absolute TX output power. On the midchannel, with TxdBCtr
set to a specified value, G_Offset is adjusted so that the output power is -8 dBm and
that value of G-Offset is recorded (which is an absolute value) in the next tuning. (The
output power in dBm is recorded in this tuning.) After this is done on the midchannel,
the channel is changed to each of the other channels and output power is reported.
(G_Offset is not adjusted on the other channels as it was on the center channel — just
the output power is recorded.)
The result is the transmitted power in dBM, which should be -8.0 dBm +/- 0.5 dB on the
center channel.
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