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Very quick response. Very good and accurate print quality of the scanned document.
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The service manual was very usable and clear enough to see the individual values of all of the components (unlike some of the service manuals I have gotten in the past from web sites similar to this one). The price was right and the information was greatly appreciated. It helped me with an otherwise very difficult repair. It was much needed and appreciated. A faster turn around on my order would be nice, but I understand the constraints on your staff's time. Thank you for your service.
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Excellent manual. Helped me out with disassembling and troubleshooting my projector.
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thanks you are the best.Very good detail, Quick service response. A useful service manual with all details.
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Great service!!! Polecam gorąco wszystkim zainteresowanym
TEST AND MEASUREMENT
17. Repeat steps 6 to 15 for GSM 1800 on the channels listed below.
Channel Bch Lch Mch Hch Tch GSM 1800 520 630 700 810 870
6.6 I and Q Values
NOTE: By observing the image leakage and adjusting the relative gain between I and Q channels, phase error and modulation spectrum can be improved. With the I, Qch adjustment procedures the transmitter must be set to Power Level 5 (this presents the worst case of non-linearity) so care must be taken that the spectrum analyser used can accept a signal input of 33 dBm. If not, an appropriate attenuator must be used.
I, Qch Gain
IMPORTANT: I, Qch offset calibration should be done before this calibration. Spectrum Analyser Setup. centre frequency = 902.4 MHz RBW = 10 kHz VBW = 10 kHz Span = 1 MHz Sweep time = 2 sec 1. On the Channel box, highlight CHANGE CH GSM. a. Press the left-right arrow keys until channel number �62� is visible in the window. Press ENTER to select. b. Press the down-arrow key until the POWER LEVEL field is highlighted. Press the left-right arrow keys until PL5 is visible in the window. Press ENTER to select. c. Press the down arrow until the TX DATA field is highlighted. Press the left-right arrow keys until NRL 1 is visible in the window. Press ENTER to select.
Figure 6.24: Image leak ratio 2. Using the spectrum analyser measure the image leak ratio. Image leak ratio is the measured ratio of peak power and the power at 135 kHz below peak frequency.
Example: peak power (902.468 Mhz) = 33 dBm power at 135 kHz below peak power = -9 dBm image leak ratio = 33 dBm - (-9 dBm) = 42 dBm MCUK990801C8 Service Manual Section 6 � 45 � Issue 1 Revision 0
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