{"id":34890,"date":"2026-08-08T16:43:52","date_gmt":"2026-08-08T08:43:52","guid":{"rendered":"https:\/\/pxisource.com\/?post_type=product&#038;p=34890"},"modified":"2026-08-31T15:53:46","modified_gmt":"2026-08-31T07:53:46","slug":"pxi-2556","status":"publish","type":"product","link":"https:\/\/pxisource.com\/ru\/product\/pxi-2556\/","title":{"rendered":"PXI-2556"},"content":{"rendered":"<h3>PXI-2556 2.5 GHz 75 \u03a9 Dual 4\u00d71 RF Multiplexer<\/h3>\n<p>\u0417\u0435\u043c\u043b\u044f <strong>PXI-2556<\/strong> is a dual-bank 4\u00d71 PXI RF multiplexer switch module designed for routing video, broadcast and other high-frequency 75 \u03a9 signals. It contains two independently controlled multiplexers, allowing two RF signal paths to operate simultaneously.<\/p>\n<p>The multibank architecture is particularly useful for stimulus-and-response testing of video RF devices such as tuners, receivers, modulators and set-top boxes. One multiplexer bank can route a source to the device under test while the second bank routes the device response to an analyzer.<\/p>\n<p>With DC to 2.5 GHz signal coverage, low insertion loss, controlled VSWR and onboard relay-count tracking, the PXI-2556 supports repeatable RF routing in automated production, validation and laboratory test systems.<\/p>\n<h3>Key Features of the PXI-2556<\/h3>\n<ul>\n<li>Two independent 4\u00d71 RF multiplexer banks<\/li>\n<li>Eight RF channels and two common connections<\/li>\n<li>DC to 2.5 GHz frequency coverage<\/li>\n<li>75 \u03a9 nominal characteristic impedance<\/li>\n<li>Unterminated RF multiplexer architecture<\/li>\n<li>30 V maximum switching voltage<\/li>\n<li>0.5 A maximum switching or carry current per channel<\/li>\n<li>10 W maximum channel-to-common RF power<\/li>\n<li>Less than 1.7 dB insertion loss through 2.5 GHz<\/li>\n<li>Less than 1.75 VSWR through 2.5 GHz<\/li>\n<li>Greater than 40 dB typical isolation through 2.5 GHz<\/li>\n<li>Less than -50 dB typical bank-to-bank crosstalk at 2.5 GHz<\/li>\n<li>Less than 25 ps typical channel-to-channel skew<\/li>\n<li>Electromechanical latching relays<\/li>\n<li>Onboard relay-count tracking<\/li>\n<li>PXI hardware trigger support<\/li>\n<li>Ten gold-plated mini-75 \u03a9 SMB connectors<\/li>\n<li>NI-SWITCH and NI Switch Executive compatibility<\/li>\n<\/ul>\n<h3>PXI-2556 Technical Specifications<\/h3>\n<table>\n<tbody>\n<tr>\n<th>Product Model<\/th>\n<td>PXI-2556<\/td>\n<\/tr>\n<tr>\n<th>Part Number<\/th>\n<td>778572-56<\/td>\n<\/tr>\n<tr>\n<th>Product Type<\/th>\n<td>PXI RF multiplexer switch module<\/td>\n<\/tr>\n<tr>\n<th>Topology<\/th>\n<td>Dual 4\u00d71 multiplexers, dual SP4T<\/td>\n<\/tr>\n<tr>\n<th>Number of Banks<\/th>\n<td>2 independent banks<\/td>\n<\/tr>\n<tr>\n<th>Channels per Bank<\/th>\n<td>4<\/td>\n<\/tr>\n<tr>\n<th>Total RF Connections<\/th>\n<td>8 channels plus 2 common ports<\/td>\n<\/tr>\n<tr>\n<th>\u0414\u0438\u0430\u043f\u0430\u0437\u043e\u043d \u0447\u0430\u0441\u0442\u043e\u0442<\/th>\n<td>DC to 2.5 GHz<\/td>\n<\/tr>\n<tr>\n<th>Characteristic Impedance<\/th>\n<td>75 \u03a9 nominal<\/td>\n<\/tr>\n<tr>\n<th>Internal Termination<\/th>\n<td>No; unterminated signal paths<\/td>\n<\/tr>\n<tr>\n<th>Maximum Switching Voltage<\/th>\n<td>30 V<\/td>\n<\/tr>\n<tr>\n<th>Maximum Switching Current<\/th>\n<td>0,5 \u0410 \u043d\u0430 \u043a\u0430\u043d\u0430\u043b<\/td>\n<\/tr>\n<tr>\n<th>Maximum Carry Current<\/th>\n<td>0,5 \u0410 \u043d\u0430 \u043a\u0430\u043d\u0430\u043b<\/td>\n<\/tr>\n<tr>\n<th>Maximum RF Power<\/th>\n<td>10 W channel-to-common<\/td>\n<\/tr>\n<tr>\n<th>Initial DC Path Resistance<\/th>\n<td>Less than 0.35 \u03a9 typical<\/td>\n<\/tr>\n<tr>\n<th>End-of-Life Path Resistance<\/th>\n<td>1.0 \u03a9 or greater typical<\/td>\n<\/tr>\n<tr>\n<th>Insertion Loss to 1 GHz<\/th>\n<td>Less than 0.8 dB; less than 0.5 dB typical<\/td>\n<\/tr>\n<tr>\n<th>Insertion Loss to 2 GHz<\/th>\n<td>Less than 1.3 dB; less than 0.9 dB typical<\/td>\n<\/tr>\n<tr>\n<th>Insertion Loss to 2.5 GHz<\/th>\n<td>Less than 1.7 dB; less than 1.2 dB typical<\/td>\n<\/tr>\n<tr>\n<th>VSWR to 1 GHz<\/th>\n<td>Less than 1.25; less than 1.1 typical<\/td>\n<\/tr>\n<tr>\n<th>VSWR to 2 GHz<\/th>\n<td>Less than 1.5; less than 1.3 typical<\/td>\n<\/tr>\n<tr>\n<th>VSWR to 2.5 GHz<\/th>\n<td>Less than 1.75; less than 1.5 typical<\/td>\n<\/tr>\n<tr>\n<th>Typical Isolation to 1 GHz<\/th>\n<td>Greater than 47 dB<\/td>\n<\/tr>\n<tr>\n<th>Typical Isolation to 2 GHz<\/th>\n<td>Greater than 40 dB<\/td>\n<\/tr>\n<tr>\n<th>Typical Isolation to 2.5 GHz<\/th>\n<td>Greater than 40 dB<\/td>\n<\/tr>\n<tr>\n<th>Bank-to-Bank Crosstalk to 1 GHz<\/th>\n<td>Less than -58 dB typical<\/td>\n<\/tr>\n<tr>\n<th>Bank-to-Bank Crosstalk to 2 GHz<\/th>\n<td>Less than -53 dB typical<\/td>\n<\/tr>\n<tr>\n<th>Bank-to-Bank Crosstalk to 2.5 GHz<\/th>\n<td>Less than -50 dB typical<\/td>\n<\/tr>\n<tr>\n<th>Channel-to-Channel Skew<\/th>\n<td>Less than 25 ps typical<\/td>\n<\/tr>\n<tr>\n<th>Propagation Delay<\/th>\n<td>1.0 ns typical<\/td>\n<\/tr>\n<tr>\n<th>Rise Time<\/th>\n<td>75 ps typical, 10% to 90%<\/td>\n<\/tr>\n<tr>\n<th>\u0422\u0438\u043f \u0440\u0435\u043b\u0435<\/th>\n<td>Electromechanical, latching<\/td>\n<\/tr>\n<tr>\n<th>Maximum Relay Operate Time<\/th>\n<td>10.4 ms<\/td>\n<\/tr>\n<tr>\n<th>Maximum Scan Rate<\/th>\n<td>Approximately 45 channels\/s<\/td>\n<\/tr>\n<tr>\n<th>Mechanical Relay Life<\/th>\n<td>1 \u00d7 10<sup>6<\/sup> cycles<\/td>\n<\/tr>\n<tr>\n<th>Electrical Relay Life<\/th>\n<td>3 \u00d7 10<sup>5<\/sup> cycles at 30 V and 10 mA resistive<\/td>\n<\/tr>\n<tr>\n<th>Input Trigger Sources<\/th>\n<td>PXI trigger lines 0 through 7<\/td>\n<\/tr>\n<tr>\n<th>Minimum Input Trigger Pulse Width<\/th>\n<td>150 ns with digital filtering enabled<\/td>\n<\/tr>\n<tr>\n<th>Output Trigger Destinations<\/th>\n<td>PXI trigger lines 0 through 7<\/td>\n<\/tr>\n<tr>\n<th>Output Trigger Pulse Width<\/th>\n<td>Programmable from 1 \u00b5s to 62 \u00b5s<\/td>\n<\/tr>\n<tr>\n<th>Front-Panel Connectors<\/th>\n<td>10 gold-plated mini-75 \u03a9 SMB jacks<\/td>\n<\/tr>\n<tr>\n<th>PXI Power Requirement<\/th>\n<td>3.7 W at 5 V and 0.3 W at 3.3 V<\/td>\n<\/tr>\n<tr>\n<th>\u041f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0430 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f<\/th>\n<td>NI-SWITCH and NI Switch Executive<\/td>\n<\/tr>\n<tr>\n<th>\u0428\u0438\u043d\u043d\u044b\u0439 \u0438\u043d\u0442\u0435\u0440\u0444\u0435\u0439\u0441<\/th>\n<td>PXI<\/td>\n<\/tr>\n<tr>\n<th>Module Format<\/th>\n<td>3U, single-slot PXI\/cPCI module<\/td>\n<\/tr>\n<tr>\n<th>Dimensions<\/th>\n<td>21.6 \u00d7 2.0 \u00d7 13.0 cm<\/td>\n<\/tr>\n<tr>\n<th>Weight<\/th>\n<td>Approximately 227 g<\/td>\n<\/tr>\n<tr>\n<th>Operating Temperature<\/th>\n<td>0\u00b0C to 55\u00b0C<\/td>\n<\/tr>\n<tr>\n<th>Storage Temperature<\/th>\n<td>-20\u00b0C to 70\u00b0C<\/td>\n<\/tr>\n<tr>\n<th>Product Status<\/th>\n<td>Discontinued by NI<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>PXI-2556 Part Number and Accessories<\/h3>\n<table>\n<tbody>\n<tr>\n<th>Item<\/th>\n<th>Part Number<\/th>\n<th>\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435<\/th>\n<\/tr>\n<tr>\n<td>PXI-2556<\/td>\n<td>778572-56<\/td>\n<td>2.5 GHz, 75 \u03a9, dual 4\u00d71 PXI RF multiplexer switch module<\/td>\n<\/tr>\n<tr>\n<td>Mini-75 \u03a9 SMB Cable<\/td>\n<td>197211-0R3<\/td>\n<td>0.3 m mini-75 \u03a9 SMB plug-to-plug coaxial cable<\/td>\n<\/tr>\n<tr>\n<td>Mini-75 \u03a9 SMB Cable<\/td>\n<td>197211-01<\/td>\n<td>1 m mini-75 \u03a9 SMB plug-to-plug coaxial cable<\/td>\n<\/tr>\n<tr>\n<td>Type F to Mini-75 \u03a9 SMB Cable<\/td>\n<td>197210-0R3<\/td>\n<td>0.3 m Type F female to mini-75 \u03a9 SMB plug coaxial cable<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>The PXI-2556 uses ten specialized mini-75 \u03a9 SMB connectors. Standard 50 \u03a9 SMB and SMA cables are not direct substitutes. Verify the impedance, connector geometry, cable length and destination interface before ordering.<\/p>\n<h3>Dual 4\u00d71 Multiplexer Architecture<\/h3>\n<p>The PXI-2556 contains two independent multiplexer banks identified as Bank A and Bank B. Each bank provides four selectable channels and one common connection.<\/p>\n<p>Bank A contains CH0A through CH3A and COM A. Bank B contains CH0B through CH3B and COM B. The selected channel in each bank connects to its corresponding common port.<\/p>\n<p>The two banks can operate independently, allowing the module to maintain two different RF routes at the same time.<\/p>\n<h3>Parallel Stimulus-and-Response Testing<\/h3>\n<p>The dual-bank design is useful when a device must receive an RF stimulus while its output is measured simultaneously. One bank can route a generator to the DUT input, while the second bank routes the DUT output to an analyzer.<\/p>\n<p>This configuration is particularly useful for testing video tuners, receivers, modulators, set-top boxes and other RF devices with distinct input and output signal paths.<\/p>\n<h3>Bidirectional RF Routing<\/h3>\n<p>Each multiplexer bank can be used in either direction. One source connected to a common port can be routed to one of four channels, or four sources connected to the channels can be selected individually for a common analyzer.<\/p>\n<p>Before connecting routes, verify that the configuration will not electrically connect incompatible sources or loads.<\/p>\n<h3>Unterminated Signal Paths<\/h3>\n<p>The PXI-2556 does not contain internal 75 \u03a9 terminations for disconnected channels. Unselected paths remain open unless external termination is installed.<\/p>\n<p>This provides lower insertion loss and avoids internal termination power limits. However, open ports can produce reflections that affect certain sources and high-frequency measurements.<\/p>\n<p>Use appropriate external 75 \u03a9 terminations when inactive channels must maintain a defined impedance.<\/p>\n<h3>75 \u03a9 Characteristic Impedance<\/h3>\n<p>The PXI-2556 is designed for 75 \u03a9 video and RF systems. This impedance is commonly used in broadcast, cable television, video distribution and related coaxial applications.<\/p>\n<p>Use 75 \u03a9 sources, loads, cables and adapters to maintain the specified insertion loss and VSWR. Mixing 50 \u03a9 and 75 \u03a9 components can create reflections and amplitude errors.<\/p>\n<h3>DC to 2.5 GHz Bandwidth<\/h3>\n<p>The module routes signals from DC through 2.5 GHz. It can handle baseband video, high-frequency video, broadcast RF, cable-device signals and other applications requiring 75 \u03a9 signal paths.<\/p>\n<p>System bandwidth depends on the complete route. Cable length, adapters, fixture layout and connected equipment can reduce overall performance.<\/p>\n<h3>\u041d\u0438\u0437\u043a\u0438\u0435 \u0432\u043d\u043e\u0441\u0438\u043c\u044b\u0435 \u043f\u043e\u0442\u0435\u0440\u0438<\/h3>\n<p>Insertion loss is specified below 0.8 dB through 1 GHz, below 1.3 dB through 2 GHz and below 1.7 dB through 2.5 GHz.<\/p>\n<p>Typical loss is below 0.5 dB at 1 GHz, below 0.9 dB at 2 GHz and below 1.2 dB at 2.5 GHz. This helps preserve signal amplitude in video and RF measurements.<\/p>\n<p>For precision measurements, characterize each switch path together with its cables and fixture, then apply frequency-dependent loss correction.<\/p>\n<h3>VSWR Performance<\/h3>\n<p>VSWR is specified below 1.25 through 1 GHz, below 1.5 through 2 GHz and below 1.75 through 2.5 GHz.<\/p>\n<p>Maintaining this performance requires correctly rated 75 \u03a9 cables and equipment. Damaged connectors, impedance-mismatched adapters and unterminated external lines can increase reflections.<\/p>\n<h3>Channel Isolation<\/h3>\n<p>Typical isolation is greater than 47 dB through 1 GHz and greater than 40 dB through 2.5 GHz.<\/p>\n<p>Isolation reduces leakage from inactive channels into a selected path. Strong RF signals can still couple through external cables or fixtures, so cable layout and shielding remain important.<\/p>\n<h3>Bank-to-Bank Crosstalk<\/h3>\n<p>Typical bank-to-bank crosstalk is below -58 dB through 1 GHz, below -53 dB through 2 GHz and below -50 dB through 2.5 GHz.<\/p>\n<p>This helps Bank A and Bank B operate simultaneously with limited interaction. For sensitive measurements, keep high-power and low-level external cables separated.<\/p>\n<h3>Propagation Delay and Skew<\/h3>\n<p>Typical propagation delay through a selected path is approximately 1 ns. Typical channel-to-channel skew is less than 25 ps, and typical 10% to 90% rise time is 75 ps.<\/p>\n<p>Use matched cable lengths when comparing signal timing or phase between different switch routes.<\/p>\n<h3>30 V, 0.5 A and 10 W Ratings<\/h3>\n<p>The PXI-2556 supports switching voltages up to 30 V and switching or carry current up to 0.5 A per channel. Maximum RF power is 10 W for each channel-to-common path.<\/p>\n<p>The signal must remain within all voltage, current and power limits simultaneously. Peak or pulsed waveforms should be evaluated using their maximum instantaneous conditions.<\/p>\n<h3>Avoid Switching Active RF Signals<\/h3>\n<p>NI recommends against switching active RF signals whenever possible. As an electromechanical relay changes state, its path becomes momentarily unterminated, which can reflect power toward the signal source.<\/p>\n<p>Reduce or disable the source before changing channels, then restore the output after relay settling. Cold switching can also improve relay life and measurement repeatability.<\/p>\n<h3>Latching Electromechanical Relays<\/h3>\n<p>The PXI-2556 uses electromechanical latching relays. A latching relay maintains its commanded state without continuously energizing its coil, helping reduce steady-state module power.<\/p>\n<p>Electromechanical contacts provide low resistance and low RF loss, but they have a finite service life. Switching high-power or reactive signals can accelerate contact wear.<\/p>\n<h3>Relay Life and Relay-Count Tracking<\/h3>\n<p>Expected mechanical relay life is approximately 1 \u00d7 10<sup>6<\/sup> cycles. Expected electrical life is approximately 3 \u00d7 10<sup>5<\/sup> cycles at 30 V and 10 mA with a resistive load.<\/p>\n<p>Onboard relay-count tracking records the activity of each signal path. Maintenance teams can identify heavily used channels and plan replacement before contact wear causes intermittent signal loss.<\/p>\n<h3>Hardware-Triggered Scanning<\/h3>\n<p>The PXI-2556 accepts triggers and exports trigger signals through PXI trigger lines 0 through 7. Hardware triggering enables deterministic coordination with RF generators, digitizers and analyzers.<\/p>\n<p>The minimum input trigger pulse width is 150 ns with digital filtering enabled. Output trigger pulse width is programmable from 1 \u00b5s to 62 \u00b5s.<\/p>\n<h3>NI-SWITCH Software Support<\/h3>\n<p>The PXI-2556 is controlled using the NI-SWITCH instrument driver. NI-SWITCH provides functions for initializing the module, connecting channels, disconnecting routes, creating scan lists, configuring triggers and reading relay counts.<\/p>\n<p>The driver supports LabVIEW, LabWindows\/CVI and compatible text-based programming environments.<\/p>\n<h3>NI Switch Executive Integration<\/h3>\n<p>NI Switch Executive allows engineers to create meaningful route names for sources, DUT connections and analyzer inputs. This reduces the need to manage physical channel identifiers directly in application code.<\/p>\n<p>Named routes can also coordinate the PXI-2556 with additional RF switch modules in larger test systems.<\/p>\n<h3>Typical PXI-2556 Applications<\/h3>\n<ul>\n<li>Parallel video tuner testing<\/li>\n<li>Stimulus-and-response RF testing<\/li>\n<li>Broadcast equipment validation<\/li>\n<li>Cable television device testing<\/li>\n<li>Set-top box functional testing<\/li>\n<li>Video receiver testing<\/li>\n<li>RF generator output routing<\/li>\n<li>Analyzer input selection<\/li>\n<li>Automated production test equipment<\/li>\n<li>75 \u03a9 component characterization<\/li>\n<li>Modulator and demodulator testing<\/li>\n<li>Video signal distribution<\/li>\n<li>Coaxial device testing<\/li>\n<li>Laboratory RF automation<\/li>\n<\/ul>\n<h3>Video Tuner Testing<\/h3>\n<p>Bank A can route one of several RF stimulus signals to a tuner input while Bank B routes one of several tuner outputs to a measurement instrument.<\/p>\n<p>This architecture enables stimulus-and-response measurements without requiring two separate switch modules.<\/p>\n<h3>Parallel DUT Testing<\/h3>\n<p>The two independent banks can also serve separate devices or fixture sections. For example, Bank A can select one DUT while Bank B selects a second signal or measurement path.<\/p>\n<p>Parallel operation must remain within the module\u2019s electrical ratings and bank-to-bank crosstalk requirements.<\/p>\n<h3>Automated Production Testing<\/h3>\n<p>The PXI-2556 replaces manual coaxial reconnection with software-controlled routes. Test sequences can select sources, DUTs and analyzers automatically.<\/p>\n<p>Relay-count tracking helps production engineers plan maintenance and reduce unexpected downtime caused by worn switch contacts.<\/p>\n<h3>PXI-2556 Troubleshooting<\/h3>\n<h4>The PXI-2556 Is Not Detected in NI MAX<\/h4>\n<p>Confirm that the module is fully installed in a compatible PXI or hybrid slot. Check chassis power, controller communication and NI-SWITCH installation, then restart the system.<\/p>\n<h4>No Signal Reaches the Common Port<\/h4>\n<p>Verify the selected bank and channel. Check the mini-75 \u03a9 SMB cables, source output, analyzer input and NI-SWITCH route configuration.<\/p>\n<h4>One Multiplexer Bank Works but the Other Does Not<\/h4>\n<p>Confirm that the application uses the correct A or B channel names and corresponding common port. Inspect the cables on the affected bank and compare its relay counts with the working bank.<\/p>\n<h4>The Signal Level Is Lower Than Expected<\/h4>\n<p>Account for module insertion loss, cable attenuation and fixture loss. Characterize each complete route when accurate amplitude correction is required.<\/p>\n<h4>The Signal Has Excessive Reflections<\/h4>\n<p>Verify that every external component uses 75 \u03a9 impedance. Add external termination to unused ports when required and replace damaged or mismatched cables.<\/p>\n<h4>A Signal in Bank A Appears in Bank B<\/h4>\n<p>Check external cable coupling, common grounding and fixture layout. Keep high-power and sensitive cables separated and verify that the observed leakage is consistent with the system isolation requirements.<\/p>\n<h4>The RF Source Shuts Down During Switching<\/h4>\n<p>The source may be detecting reflected power while the relay path is temporarily unterminated. Disable or reduce the source before switching.<\/p>\n<h4>A Channel Has Excessive Resistance<\/h4>\n<p>Inspect the external cable and connector, then compare the channel with another route. Increasing resistance may indicate relay-contact wear.<\/p>\n<h4>The Hardware Trigger Does Not Advance the Scan<\/h4>\n<p>Verify the selected PXI trigger line, direction, pulse width and scan-list configuration. Ensure that the scan has started before the first trigger arrives.<\/p>\n<h3>PXI-2556 Comparison with Similar 75 \u03a9 RF Switches<\/h3>\n<table>\n<tbody>\n<tr>\n<th>\u041c\u043e\u0434\u0435\u043b\u044c<\/th>\n<th>Primary Configuration<\/th>\n<th>Best Suited For<\/th>\n<\/tr>\n<tr>\n<td>PXI-2554<\/td>\n<td>2.5 GHz, 75 \u03a9, single 4\u00d71 multiplexer<\/td>\n<td>One unterminated four-channel RF route<\/td>\n<\/tr>\n<tr>\n<td>PXI-2555<\/td>\n<td>2.5 GHz, 75 \u03a9, terminated 4\u00d71 multiplexer<\/td>\n<td>Maintaining 75 \u03a9 loading on inactive channels<\/td>\n<\/tr>\n<tr>\n<td>PXI-2556<\/td>\n<td>2.5 GHz, 75 \u03a9, dual 4\u00d71 multiplexer<\/td>\n<td>Parallel stimulus-and-response signal routing<\/td>\n<\/tr>\n<tr>\n<td>PXI-2557<\/td>\n<td>2.5 GHz, 75 \u03a9, single 8\u00d71 multiplexer<\/td>\n<td>Higher-channel-count selection to one common port<\/td>\n<\/tr>\n<tr>\n<td>PXI-2558<\/td>\n<td>2.5 GHz, 75 \u03a9, quad SPDT RF relay<\/td>\n<td>Custom RF changeover and routing networks<\/td>\n<\/tr>\n<tr>\n<td>PXI-2559<\/td>\n<td>75 \u03a9 RF relay architecture<\/td>\n<td>Independent general-purpose video RF switching<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>PXI-2556 vs PXI-2554<\/h3>\n<p>The PXI-2554 contains one 4\u00d71 multiplexer, while the PXI-2556 contains two independent 4\u00d71 banks. Both are unterminated 75 \u03a9 modules with similar RF path specifications.<\/p>\n<p>Select the PXI-2554 when only one route is required. Choose the PXI-2556 when two signals must be switched simultaneously or when stimulus and response paths must be controlled independently.<\/p>\n<h3>PXI-2556 vs PXI-2555<\/h3>\n<p>The PXI-2555 contains one internally terminated 4\u00d71 bank. The PXI-2556 contains two unterminated 4\u00d71 banks.<\/p>\n<p>Select the PXI-2555 when inactive channels must remain connected to 75 \u03a9 loads. Choose the PXI-2556 when two independent paths and lower insertion loss are more important.<\/p>\n<h3>PXI-2556 vs PXI-2557<\/h3>\n<p>The PXI-2556 divides eight channels into two independent 4\u00d71 banks. The PXI-2557 combines eight channels into one 8\u00d71 multiplexer.<\/p>\n<p>Choose the PXI-2556 for two simultaneous four-channel routes. Select the PXI-2557 when one source or analyzer must select between as many as eight channels.<\/p>\n<h3>Recommended Related Products<\/h3>\n<ul>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product\/pxi-2554\/\">PXI-2554 4\u00d71 RF Multiplexer<\/a><\/li>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product\/pxi-2555\/\">PXI-2555 Terminated 4\u00d71 RF Multiplexer<\/a><\/li>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product\/pxi-2557\/\">PXI-2557 8\u00d71 RF Multiplexer<\/a><\/li>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product\/pxi-2558\/\">PXI-2558 Quad SPDT RF Relay Module<\/a><\/li>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product\/pxi-2559\/\">PXI-2559 75 \u03a9 RF Relay Module<\/a><\/li>\n<li><a href=\"https:\/\/pxisource.com\/ru\/product-category\/%d0%bd%d0%b8\/pxi-%d1%81%d0%b8%d1%81%d1%82%d0%b5%d0%bc%d1%81\/%d0%bc%d0%be%d0%b4%d1%83%d0%bb%d0%b8-pxi\/\">View More NI PXI and PXI Express Modules<\/a><\/li>\n<\/ul>\n<h3>Selecting the Right 75 \u03a9 RF Multiplexer<\/h3>\n<p>Choose the PXI-2556 when the test system requires two independent 4\u00d71 RF paths, operation through 2.5 GHz and 75 \u03a9 signal compatibility.<\/p>\n<p>Select the PXI-2554 for one four-channel path, the PXI-2555 for terminated operation or the PXI-2557 when eight channels must share one common instrument connection.<\/p>\n<h3>Why Choose the PXI-2556?<\/h3>\n<ul>\n<li>Provides two independent 4\u00d71 multiplexers<\/li>\n<li>Supports simultaneous stimulus-and-response routing<\/li>\n<li>Routes signals from DC through 2.5 GHz<\/li>\n<li>Maintains 75 \u03a9 video and RF signal paths<\/li>\n<li>Provides low insertion loss<\/li>\n<li>Handles up to 30 V, 0.5 A and 10 W<\/li>\n<li>Offers controlled VSWR and bank isolation<\/li>\n<li>Includes onboard relay-count tracking<\/li>\n<li>Supports deterministic hardware triggering<\/li>\n<li>Integrates with NI-SWITCH and NI Switch Executive<\/li>\n<\/ul>\n<h3>Frequently Asked Questions<\/h3>\n<h4>What is the PXI-2556?<\/h4>\n<p>The PXI-2556 is a 2.5 GHz, 75 \u03a9 PXI RF switch module containing two independent 4\u00d71 multiplexers.<\/p>\n<h4>What is the PXI-2556 part number?<\/h4>\n<p>The standard NI part number is <strong>778572-56<\/strong>.<\/p>\n<h4>How many RF channels does it provide?<\/h4>\n<p>The module provides eight channels divided between two banks, with four channels and one common port in each bank.<\/p>\n<h4>What is the frequency range?<\/h4>\n<p>The PXI-2556 routes signals from DC through 2.5 GHz.<\/p>\n<h4>Are the disconnected channels internally terminated?<\/h4>\n<p>No. The PXI-2556 has an unterminated topology. External 75 \u03a9 termination may be added when required.<\/p>\n<h4>Can both multiplexer banks operate simultaneously?<\/h4>\n<p>Yes. Bank A and Bank B are independently controlled and can maintain separate signal routes at the same time.<\/p>\n<h4>What is the maximum RF power?<\/h4>\n<p>Maximum channel-to-common RF power is 10 W, subject to the 30 V and 0.5 A limits.<\/p>\n<h4>What is the maximum insertion loss?<\/h4>\n<p>Insertion loss is less than 0.8 dB through 1 GHz, less than 1.3 dB through 2 GHz and less than 1.7 dB through 2.5 GHz.<\/p>\n<h4>What type of connectors does it use?<\/h4>\n<p>The front panel provides ten gold-plated mini-75 \u03a9 SMB connectors.<\/p>\n<h4>Does it support relay-count tracking?<\/h4>\n<p>Yes. Onboard relay-count tracking helps monitor usage and schedule preventive maintenance.<\/p>\n<h4>Which software controls the PXI-2556?<\/h4>\n<p>The module is controlled using NI-SWITCH and can be integrated into named-route applications with NI Switch Executive.<\/p>\n<h4>Is the PXI-2556 still available from NI?<\/h4>\n<p>No. NI identifies the PXI-2556 as no longer available. Used, refurbished and new-surplus modules may remain available through specialized suppliers.<\/p>\n<h3>Request a Quote for the PXI-2556<\/h3>\n<p>Contact us for current availability, condition, testing options and project pricing for the <strong>PXI-2556 2.5 GHz 75 \u03a9 Dual 4\u00d71 RF Multiplexer<\/strong>. We can also help identify compatible mini-75 \u03a9 SMB cables, PXI chassis and related PXI-2554, PXI-2555 or PXI-2557 modules.<\/p>","protected":false},"excerpt":{"rendered":"<p>PXI-2556 2.5 GHz 75 \u03a9 Dual 4\u00d71 RF Multiplexer The PXI-2556 is a dual-bank 4\u00d71 PXI RF multiplexer switch module<\/p>","protected":false},"featured_media":34814,"template":"","meta":{"_acf_changed":false},"product_brand":[18],"product_cat":[667],"product_tag":[],"class_list":["post-34890","product","type-product","status-publish","has-post-thumbnail","product_brand-national-instruments","product_cat-pxi-modules","first","instock","shipping-taxable","product-type-simple"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v25.0 (Yoast SEO v28.4) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>NI PXI-2556 PXI RF Multiplexer Switch Module 778572-56, In Stock | Project Pricing<\/title>\n<meta name=\"description\" content=\"The PXI-2556 is a 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