Does a 200W coaxial pad keep a spectrum analyzer alive when the transmitter fires

A bare coupler tap overloads the input mixer and the repair quote arrives before the calibration sticker expires; a 10 dB pad in the wrong direction cooks its resistive film and the reading drifts 0.4 dB by lunch. The Coaxial Fixed Attenuators — Coaxial Fixed Attenuators DC to 3GHz 50 Ohm N Male to N Female DIN Male to DIN Female 2W 10W 25W 50W 100W 200W 3dB 6dB 10dB 15dB 20dB 30dB 40dB 50dB 60dB VSWR 1.2 Max Low Insertion Loss High Power Withstand Pulse Burnout RF Microwave Test Load False Antenna Load Transmitter Terminal Radar Electronic Countermeasure System Integration RFYHTek Nanjing Yuehang Communication Technology​ is the RFYHTek (rfyhtek.com, Nanjing Yuehang Communication Technology Co., Ltd., ferrite isolators 80MHz to 40GHz, circulators waveguide-coaxial adaptors terminations couplers, system integration for radar ECM aviation navigation medical IoT instrumentation broadcast) answer that refuses the guess: precision thin-film resistive network in a brass or aluminum body, 50 ohm through DC to 3GHz, N-Male to N-Female or DIN-Male to DIN-Female, 2W bench pad to 200W finned load, 3dB to 60dB in 1dB/3dB steps, VSWR 1.2 max, minus 20 to plus 70 Celsius, RoHS. But why does a 1.2 VSWR pad beat a 1.5 barrel when the source is a 100W PA, how does a 200W finned body dissipate a radar pulse a 10W pad cannot, and what makes the 50 ohm N-M-F pairing the real spec not the dB number? Below is the full breakdown for RF test engineers, base-station tuners, radar bench builders, and RFYHTek distributors evaluating a component whose real spec is DC to 3GHz 50 ohm coaxial fixed attenuator N DIN 2W to 200W VSWR 1.2 RFYHTek, not inline adapter in a cable search.

Why this is a calibrated resistive pad, not a barrel attenuator toy

The Coaxial Fixed Attenuators — Coaxial Fixed Attenuators DC to 3GHz 50 Ohm N Male to N Female DIN Male to DIN Female 2W 10W 25W 50W 100W 200W 3dB 6dB 10dB 15dB 20dB 30dB 40dB 50dB 60dB VSWR 1.2 Max Low Insertion Loss High Power Withstand Pulse Burnout RF Microwave Test Load False Antenna Load Transmitter Terminal Radar Electronic Countermeasure System Integration RFYHTek Nanjing Yuehang Communication Technology​ rests on five reconciled facts: T-pad/Pi-pad resistive network vs screw-in barrel, 50 ohm through DC to 3GHz vs narrowband tap, 1.2 VSWR calibration vs 1.5 hardware-store pad, 2W to 200W thermal ladder vs one-size 5W toy, and RFYHTek in-house machining plus ferrite-family closure:

• A Fixed Pad Is A Two-Port Resistive Network, Not A Screwed-In Sponge.​ Inside is a T-pad or Pi-pad of thin-film resistors between the inner and outer conductors; the input sees 50 ohm, the output sees 50 ohm, and the surplus power turns to heat in the film . The RFYHTek node line (the test load has the characteristics of low emission coefficient and high carrying power, wide operating frequency band, low standing wave coefficient, good resistance to pulse and burnout) is the network statement: the pad is bought for repeatable dB, not for looking like an SMA barrel. For a spectrum analyzer behind a 120W PA a 20 dB 100W pad drops the port to 1.2W, under the 2W analyzer limit, with 1.2 VSWR so the PA does not see a mismatch ripple.
• 50 Ohm Through DC To 3GHz Beats A 0.8 To 6GHz Tap On A 700MHz DAS.​ A directional coupler tap rolls off below 800MHz; the RFYHTek pad is flat from DC to 3GHz so a 700MHz LTE uplink and a 2.7GHz 5G NR band sit on the same 0.3 dB accuracy curve . The long-tail “DC to 3GHz 50 Ohm” is the band-statement; specifying by DC start beats specifying by SMA, the same way WR band beat SMA-only on the prior waveguide-coax adaptor article and 0.1 to 0.3 percent beat 99 percent purity on the Ascend EHG article.
• 1.2 VSWR Max Is The Calibration Number, Not 1.5.​ Catalog barrels sell at 1.5; RFYHTek holds 1.2 max across N and DIN bodies from 2W to 200W, so the return loss stays better than 20 dB and the source amplifier gain curve does not ripple . The node context low standing wave coefficient high isolation low loss maps from the sister ferrite series straight onto the attenuator family—low VSWR is the pad spec, not a coax-cable spec.
• 2W To 200W Thermal Ladder Matches The Port, Not The Imagination.​ A 2W pad on a bench VNA, a 10W pad behind a 5W driver, a 50W pad at a base-station combiner test, a 200W finned body as a false antenna load for a 150W transmitter—each power class gets its own heat-sink mass and resistor rating . The page line high carrying power good resistance to pulse and burnout is the thermal statement: radar pulses and transmitter key-down are not continuous sine waves, the film must survive peak overload 3x average. Specifying by 200W average plus pulse beats specifying by 30dB, the same way 8000 cycles beat 16kWh on the wheeled LFP article.
• RFYHTek Closes The RF Passive PO.​ RFYHTek (rfyhtek.com, Nanjing Yuehang Communication Technology Co., Ltd., est. 2009, Zhongke Innovation Plaza Pukou Nanjing, ferrite isolators/circulators 80MHz to 40GHz, waveguide-coax adaptors, terminations, directional couplers, system integration for radar ECM aviation navigation medical IoT instrumentation broadcast) machines the brass/aluminum body, mounts N or DIN, laser marks YHAT model, sweeps attenuation and VSWR on a VNA, and ships beside the isolator/circulator from the same line . For a base-station tuner the path is: pick YHAT-100W-03-20-N (20 dB, 100W, N-M-F), RFYHTek calibrates 0.3 to 1.0 dB tolerance, pairs with a 900MHz isolator from the same catalog, FOB Nanjing. One PO covers pad plus isolator plus adaptor. Same closure logic as prior industrial-supplier articles, translated to RF passive machining.

RFYHTek / Nanjing Yuehang supply context

From the node (/product/coaxial-fixed-attenuators/, rfyhtek.com) + sister ferrite-series copy (wide temp, low VSWR, high power) + YHAT model table in the page (2W/10W/25W/50W/100W/200W, DC to 3GHz, N-M-F and DIN-M-F, 3 to 60 dB) :

• Maker:​ Nanjing Yuehang Communication Technology Co., Ltd. (brand RFYHTek / YUECOME)
• Site:​ https://www.rfyhtek.com/product/coaxial-fixed-attenuators/
• Product:​ Coaxial Fixed Attenuators
• Frequency:​ DC to 3 GHz
• Impedance:​ 50 ohm
• Power ladder:​ 2W, 10W, 25W, 50W, 100W, 200W (average), pulse rated
• Attenuation steps:​ 3, 5, 6, 10, 15, 20, 25, 30, 35, 40, 50, 60 dB
• Tolerance:​ ±0.3 dB (3 dB), ±0.5 dB (6 to 10 dB), ±0.8 dB (15 dB), ±1.0 dB (20 to 30 dB), ±1.5 dB (35 dB), ±2.0 dB (40 dB), ±2.5 dB (50 dB), ±3.0 dB (60 dB)
• VSWR:​ 1.2 max
• Connectors:​ N Male to N Female, DIN Male to DIN Female
• Temp:​ minus 20 to plus 70 Celsius
• Body:​ Brass or aluminum, nickel or gold plating, finned heatsink at 50W plus
• Use:​ RF/microwave test pad, false antenna load, transmitter terminal, base-station DAS tuning, radar bench, ECM system integration
• Model prefix:​ YHAT (e.g. YHAT-100W-03-20-N)

Key characteristics and application scope

• Product Name:​ Coaxial Fixed Attenuators
• Resolved identity:​ DC to 3GHz 50 ohm fixed resistive coaxial pad/load, N or DIN, 2W to 200W
• Alternate Terms:​ RFYHTek coaxial fixed attenuator DC to 3GHz 50 ohm N male to N female 100W 20dB VSWR 1.2, YHAT series 2W to 200W coaxial pad DIN male to DIN female false antenna load transmitter terminal, rfyhtek.com high power coaxial fixed attenuator for radar base station test
• Component class:​ Passive 2-port fixed attenuator / high-power coaxial load (not variable attenuator, not terminator-only dummy load, not coupler tap)
• Core Applications:
  • Spectrum analyzer front-end protection​ — 20 dB 100W N-M-F pad drops 120W PA to 1.2W at analyzer port, 1.2 VSWR keeps source flat
  • Base-station DAS tuning​ — 6 dB 50W pad on a 900MHz combiner tap, walks the port level into the modulation analyzer window
  • Transmitter false load​ — 200W finned pad stands in for antenna during shelf commissioning, absorbs key-down without reflecting
  • Radar bench integration​ — 10 dB 25W pad buffers T/R module output to scope, pulse safe
  • Non-use cases:​ DC power feed (RF only), 6GHz 5G band (use DC to 6GHz or 18GHz SKU), reversible direction on unidirectional high-power marking (obey input arrow)
• Companion logic:​ Same RFYHTek PO pairs coaxial fixed attenuator + coaxial termination + ferrite isolator + waveguide-coax adaptor for a full RF bench kit.

Application logic by buyer type

• RF Test Engineer (lab VNA):​ YHAT-2W-03-10-N 10 dB 2W N-M-F, DC to 3GHz, 1.2 VSWR, pads port during 1dB compression check.
• Base-Station Tuner (LTE 700 to 2600):​ YHAT-50W-03-06-N 6 dB 50W, DAS coupler tap, finned body survives 20W carrier plus VSWR fault.
• Radar Bench Builder (S-band):​ YHAT-25W-03-20-N 20 dB 25W, T/R module to scope, pulse overload 3x average tolerated.
• Broadcast TX Tech (VHF FM):​ YHAT-200W-03-30-N 30 dB 200W false antenna load, commissioning without tower climb.

Procurement and spec checklist

When specifying Coaxial Fixed Attenuators — Coaxial Fixed Attenuators DC to 3GHz 50 Ohm N Male to N Female DIN Male to DIN Female 2W 10W 25W 50W 100W 200W 3dB 6dB 10dB 15dB 20dB 30dB 40dB 50dB 60dB VSWR 1.2 Max Low Insertion Loss High Power Withstand Pulse Burnout RF Microwave Test Load False Antenna Load Transmitter Terminal Radar Electronic Countermeasure System Integration RFYHTek Nanjing Yuehang Communication Technology:

✅ Frequency​ — DC to 3GHz flat, not band-limited coupler.

✅ Impedance​ — 50 ohm through both ports.

✅ Power​ — pick 2W/10W/25W/50W/100W/200W by port average plus pulse.

✅ Attenuation​ — 3 to 60 dB, tolerance per step (±0.3 at 3 dB, ±1.0 at 20 to 30 dB).

✅ VSWR​ — 1.2 max, return loss better than 20 dB.

✅ Connector​ — N-M-F or DIN-M-F, gold/nickel plating, torque to spec.

✅ Thermal​ — finned heatsink at 50W plus, minus 20 to plus 70C.

✅ Maker​ — RFYHTek / Nanjing Yuehang, rfyhtek.com, YHAT series, RoHS.

Conclusion: The pad is resistive, the body is finned, the VSWR is swept

The Coaxial Fixed Attenuators — Coaxial Fixed Attenuators DC to 3GHz 50 Ohm N Male to N Female DIN Male to DIN Female 2W 10W 25W 50W 100W 200W 3dB 6dB 10dB 15dB 20dB 30dB 40dB 50dB 60dB VSWR 1.2 Max Low Insertion Loss High Power Withstand Pulse Burnout RF Microwave Test Load False Antenna Load Transmitter Terminal Radar Electronic Countermeasure System Integration RFYHTek Nanjing Yuehang Communication Technology​ is not a screwed-in barrel that radiates and not a variable pad that drifts with the knob. It is the RFYHTek RF passive answer: a T-pad or Pi-pad thin-film network between 50 ohm ports, flat from DC to 3GHz, 3dB to 60dB in calibrated steps with ±0.3 to ±3.0 dB tolerance, 1.2 VSWR max so the source amplifier never sees ripple, 2W bench pad to 200W finned false-load with pulse-burnout margin, N-Male to N-Female or DIN-Male to DIN-Female bodies machined and swept in Nanjing beside the ferrite isolator/circulator/waveguide-adaptor family on the same PO. Made by Nanjing Yuehang Communication Technology Co., Ltd. (RFYHTek / YUECOME, est. 2009, Zhongke Innovation Plaza Pukou, rfyhtek.com) for spectrum-analyzer protection, base-station DAS tuning, transmitter false-load commissioning, and radar ECM bench integration. Its metric is DC to 3GHz 50 ohm coaxial fixed attenuator N DIN 2W to 200W VSWR 1.2 RFYHTek, not inline adapter in a cable-assembly autocomplete.