10GHz LNB with EXT OSC manual
This LNB 10 GHz with external reference is LNB (Low Noise Block) modified for external 25 MHz reference for internal PLL. This signal is feeded by the same one coaxial cable as IF down. Special small Bias Tee box with TCXO or 10 MHz reference signal works as DC injector and also 25 MHz source for LNB. There is also variable attenuator for IF signal which allows you to change IF signal from 0 to maximum. You can still switch between V and H polarisation by supply voltage.
block diagram of the Bias Tee box
signal source external 10 MHz
⚠ This is default preset configuration - if you like to use TCXO, please open the box and reconfigure jumpers
signal source TCXO
trimmer works as variable attenuator
LNB & Bias Tee classic version
LNB & Bias Tee with POTY adapter
power supply cable
Bias Tee LNB BOX
- small box works as DC Bias Tee, 25 MHz source for LNB, variable ATT and protections
- allows you to supply DC voltage and 25 MHz reference for PLL of LNB over one coax
- you can use internal TCXO with 0.2 ppm or some 10 MHz reference signal (you can select signal by the jumper JP1)
- you can switch H and V polarisation
- DC and RF protections!
- Variable attenuator! (blue trimmer works as variable attenuator)
- DC plug included
Poty dual band antenna adapter
- PETG UV stable material
- 22 mm Cu pipe size (use tape to waterproof it)
- POTY pipe WG fixed by M4 screw
- ONLY ADAPTER, 2.4 GHz antenna NOT included!
|LNB local oscillator||9750 MHz (with 25 MHz source)|
|Conversion gain of LNB||> 50 dB|
|LNB IF||739 MHz for 10489 MHz (QO-100)
618 MHz for 10368 MHz
|Reference 10 MHz input power||-3 dBm to +13 dBm|
|Stability with 10 MHz reference||depends on reference source|
|Stability with 25 MHz TCXO (0.2 ppm)||0.2 ppm (X 390)|
|25 MHz cut off to RX output port||> 50 dB|
|Frequency error with TCXO||max 3 kHz, typ. less than 1 kHz (after 5 minutes)|
|DC power||+12 V for Vertical polarisation (NB)
+15 V for Horizontal (WB)
|Bias Tee IF loss||typ. less than 2 dB|
|Variable Attenuator on IF||0 dB to NO signal|
⚠ IMPORTANT NOTE: This Bias Tee box is designed for 10 MHz external reference source but you can also use internal 25 MHz TCXO, which is 0.2 ppm. Frequency error is max. 3 kHz.
⚠ IMPORTANT NOTE: Do NOT forget that the quality of the 10 MHz signal source has got final effect on the quality of the output signal. With added phase noise by PLL multiplying.
MK II: Internal duplexer - cut off 25 MHz signal to RX output
10 368 MHz to 618 MHz locked to external 10MHz reference
10 499 MHz to 749 MHz locked to external 10 MHz reference
Effect of GPSDO-TCXO
Options: Recommendations to buy
- 10 MHz reference source locked to GPS signal
- RF output typ +5 dBm
- HW by BG7TBL, modification by OK2ZAW
- including GPS antenna and DC power cable
- 3.5 mm jack with GPS data out
- including coax cable with BNC and SMA (about 50 cm)
- please be patience, GPS lock could take long time at first time, also depends on the GPS satellite count etc.
- small splitter for 10 MHz reference signal
- splits 10 MHz signal to Bias Tee box and another your device (SDR, TRX etc.)
- low loss 3.5 dB
- RTL-SDR USB receiver
- in metal box
- 1 ppm TCXO for better stability
- input SMA connector
- firmware already installed
- 8 bit, up to 2 MHz of spectrum
- compatible with HDSDR, SDR console etc.
- SMA male & SMA male pigtail
- about 15 cm (total length 17 cm)
- This is Low Noise Block (LNB) which works as Down Converter. You can use it for input frequency in range of 10 to 12 GHz. In amateur radio world you can build 10 GHz RX for QO-100 satellite, 10 GHz EME or tropo.
- Device is designed only for Receiving.
- Input of LNB is designed for 10 to 12,5 GHz. Original local oscillator (LO) is locked by 25 MHz reference signal and multiplied 390 - what means 9750 MHz. You can use different reference signals 25MHz +- to change LO frequency.
IF = Input - LO [MHz]
- For example IF = 432 MHz and Input = 10489 MHz
LO = 10489 - 432
LO = 10057 MHz
- There is Variable Attenuator (ATT) trimmer. You can reduce signal strength as you need because the gain of LNB is high.
- LNB with internal TCXO need some warm up time. Depends on the outside temperature, it is around 5 minutes. If you have small signal moving it can be problem of antenna dish (LNB) vibration.
- LNB with external TCXO has got stability around 1ppm stability. Signal can move by a few Hz in the short time period. LNB with external reference signal is locked to the external oscillator and stability is based on stability by this one multiplied by 390.
- with voltage 11 to about 14 Volts the LNB has got Vertical polarisation, with Voltage over 15 V it is Horizontal.
- We offer also LNB with POTY adapter. You can insert 22mm copper pipe as waveguide (WG) and part of YOUR POTY antenna.
- 2,4 GHz POTY antenna is not included. Only 3D printed adapter.
- Please, isolate WG pipe to 3D printed adapter against the water!
- Do not forget, that dish antenna has got right FOCUS place. LNB holder is designed to mount LNB into the right place for maximal GAIN and also LOWER noise of the dish antenna. When you use POTY antenna, you have to place open part of the WG to the FOCUS. If you place LNB to the holder and POTY is in front of it, you degrade parameters of antenna a lot!
- There is usually problem with the size of the POTY reflector and place in the original LNB holder of the dish antenna.
- Example of the right way of the mounting: amsat forum.