MFJ MFJ-8504, Инструкция по эксплуатации

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Quick Start
1. Connect your receiver(s) to the output ports, antenna(s) to the antenna ports.
Note: Unless optional band splitting filters are installed and internal input jumpers are
reconfigured, antenna port 1 is the only active input port. Receiver port 1 is the primary active
output port. Receivers connected to ports 2-4 will function, but it is best to remove the appropriate
black jumper shunt terminating ports 2-4 when using a port.
2. Connect a 12Vdc nominal voltage, 150 mA or higher power source to the right rear standard
power connector. The plug must be center pin positive. Use a good well-filtered supply.
Connectors
The MFJ-8504 has two standard BNC input connectors. It is best to keep the receive antenna(s) well
away from any transmitting antennas. This unit is generally as safe as any SDR receiver.
The maximum safe net power applied to these terminals is 20 dBm or 3.2 volts peak. With filters safe
level fully outside filter pass band can be up to 15 volts RMS (36 dBm).
The MFJ-8504S has four standard SMA output connectors. The MFJ-8504B has four standard BNC
output connectors. For best performance unused outputs should be terminated with 50-75 ohm
terminations. Terminations are built in to the units.
Provisions have been made for the following. (These features require purchase of additional high pass
and low pass filters).
Frequency split to dual inputs this feature allows separate low band / high band antennas. Any filter
can be used separately on any antenna input port. Filters can also be connected in parallel or in series
from a single port. We currently have an 8-pole broadcast band reject, 1.7 MHz 5-pole High Pass, and 30
MHz Low Pass and High Pass 5-pole filters. The filters can be set up in multiple ways for specific needs.
The user must calculate the values and make his own non-standard filters.
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Band Pass 10-pole filters allow selection of a favorite pass band of limited bandwidth such as
broadcast or a particular Ham band.
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Band-reject 8-pole filters reject an undesired frequency range such as the AM broadcast band.
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Low Pass 5-pole filter passes all frequencies above a cut off limit.
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High Pass 5-pole filter passes all frequencies below cut off limit.
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Low Pass and High Pass can be used in tandem to form a wide Band Pass or wide band reject of
almost any width. For example a 1.7MHz High Pass can be used in series with a 30MHz Low
Pass to form a 1.7-30MHz Band Pass. A 1.7MHz Low Pass is in parallel with a 30 MHz High
Pass forms a 1.7-30 MHz band reject.
This unit allows any configuration of up to two filters.
Typical Configuration
Connect a 9-15 Vdc, 150 mA or higher power source to the right rear 2.1 mm 12V connector. The plug
must be center pin positive, negative to the outer shell. Be sure the power source is relatively clean of
hum and high frequency noises. While the power jack is noise filtered and decoupled, some power
supplies can introduce noise or repeating birdies. This is especially true if your antenna system and cable
wiring has poor common mode current isolation.
In rare cases isolating the power supply from other devices, such as using a dedicated higher-quality
linear (non-switch mode) wall supply, might be necessary.
Receiver 1 is the priority receiver output. This should be the first receiver port connected. This unit is
shipped with additional Receiver ports terminated in 50 ohms internally. If additional Receiver ports are
used, they can be added in any order.