YO4HFU
ALCATEL 11GHz RADIO LINK MODIFIED TO 10GHz

ALCATEL-LUCENT 9500MPR (Microwave Packet Radio) link is available for microwave bands between 6-38GHz.
The 9500 MPR series has several types of ODU (Out Door Unit) wich can be connected by coaxial cable, Ethernet or fiber optic.
Below we will discuss only about ODU300 version (single coaxial cable).

Some specifications extracted from the user manual:



According ODU TX frequency plan, Low or High TX version are available. Example of 11GHz ODU300 found:

TX LOW (Low Band LB), unknown XVRT
Tx:10915-11075 MHz
Rx:11430-1158 MHz
PN: 3DB23035HCAA01

TX HIGH (High Band HB), TR 490-530MHz, MTI XVRT
Tx: 11200-11345 MHz
Rx: 10675-10835 MHz
PN: 3DB23035HEAA02

TX HIGH (High Band HB), EXCELICS XVRT
Tx: 11310-11465MHz
Rx: 10795-10955MHz
PN: 3DB23035HFAA02



ODU 11GHz version is often available on Ebay as decommissioned equipment. Inside of ODU300 next items can be found:
- Waveguide WR90
- Duplexer filter coaxial/waveguide
- XVRT 11GHz E500
- LO PLL
- FI Board 126MHz/311Mhz
- DC/DC converter, -48V

XVRT 11GHz and LO module are the most interesting parts suitable to be reused at 10GHz due to simplicity and excellent quality.
Main RF module XVRT E500 can be found in two versions, manufactured by MTI or EXCELICS. EXCELICS version is difficult to be retuned due to bonding wires and small size microstrip filters.
Other amateurs have reported good results of EXCELICS at 10.368GHz, without any modification: Rx gain 26dB, Pout 1.6W, FI 2320MHz.

Original Rx 1st FI was found 1600MHz, BW ~90MHz, according measurement of 5 pole ceramic BPF located on FI board. Also the ceramic LPF installed after 1st Rx mixer has cutoff at 2.05GHz.
Then the signal is translated to 2nd FI 311/126MHz. 2nd IF I/O is connected to indoor modulator unit "MOD300" via coaxial feeder. Same coaxial cable is used for -48V power supply and 5.5/4.5MHz telemetry subcarrier.
Tx 1st FI is high pass filtered above 625MHz. Tx FI = [Rx FI] +/- [duplex spacing].

TX driver stage and power stage share same power bus. The voltage can be 7.7V or 10.8V according band frequency range of TRX module. Resistor R6 (not used - "open" for 10GHz MTI) located inside of TRX is monitored by CPU. It coresponding with +7.7V selection for FMM5061 driver & FLM1013-3 PA. The voltage is selected through pin 6 of -48V PSU board. Idle current (gate bias voltage) is automaticaly controlled using closed loop by monitoring FLM1013 drain current. Idle current is programmed according R3, R4 resistors. Control bias for FMM5061 is not used due to internal self biasing from -5V. So resistors R1,R2 are installed only to keep bias circuit not floating. Automatic bias circuit is located on FI board.


Two versions of MTI E500 XVRT module are available:

11GHz, Low Band, Hi-side LO Injection, P/N:131-142264-1005-01
LO = RF + IF, internal LO multiplier x4 , LO BPF 12.7...13.4GHz. FI output spectrum is reversed (mirror).

11GHz, High Band, Low-side LO Injection, P/N:131-142264-1105-01
LO = RF - IF, internal LO multiplier x3, LO BPF 9...9.7GHz. More information about Low-side version on IW0FFK website.

LO PLL (P/N: 131-142286-007) lock range is 2950-3280MHz, Uvco=Uoa=12V. Some LO boards lock up to 3225MHz at 12V. Optimum settings are CP 0.625mA, PD 1MHz but is able to lock using PD 20KHz...2.5MHz. Output level ~5dBm if supply voltage across VCO terminals is 8V. In order to preserve RF level, VCO limiting resistor R1,R5 must be decreased if external power supply is less than 12V. For 10.5V power supply of VCO, connect 100 ohms resistor in paralel with R1 or R5.

Optimal FI for 10.368GHz can be ~1500MHz. The most common SAW filters available are designed for GPS use.
Let's see frequency planning for 1st FI 1592MHz and 1218MHz:

HIGH SIDE LO, LO x4, LB Xvrt
RF = 10368MHz
LO1 = 10368MHz + 1592MHz = 11960MHz
Fimg = 11960 + 1592 = 13552MHz
LO1 VCO = 11944 / 4 = 2990MHz - 1st FI SAW GPS 1582MHz, BW 80MHz, F6QA1G582H2JM-J, excellent image/LO rejection.
LO2 = 1592 + 144 = 1736 MHz (spectrum direction restored)
LO2 = 1592 + 432 = 2024 MHz

LOW SIDE LO, LO x3, HB Xvrt
RF = 10368MHz
LO1 = 10368MHz - 1218MHz = 9150 MHz
Fimg = 9150 - 1218= 7932MHz
LO1 VCO = 9150/ 3 = 3050MHz - 1st FI SAW GPS L2 1227MHz, SF2208E. 1st FI higher than 1500MHz is not possible to due out of range PLL.
LO2 = 1218 - 144 = 1074 MHz
LO2 = 1218 - 432 = 786 MHz

Original FI board is difficult to be reused at 144MHz or 432MHz. I designed a new controller, FI convertor and PSU which can support various Alcatel 9500 XVRTs.
See FI Converter/Controller project.


XVRT MTI LB 11GHz conversion to 10GHz rev.1
XVRT 11GHZ MTI schematic rev.1.5 (reverse eng.), Hi-Side LO

LO PLL schematic rev.1.4 (reverse eng.)
XVRT MTI top
XVRT MTI bottom
XVRT EXCELICS 11GHz
LO PLL
FI Board top
FI Board bottom
FI Board - 1.6GHz Rx FI filters
ODU-300 internal view 1
ODU-300 internal view 2
IDU MOD-300, RF block

 

 

 

 

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