Aeroflex KDI | aeroflex.com/ams/kdi-rp/micro-kdi-rp-prods.cfm
Individual filter and multi-function assemblies for wireless
base station front ends, point-to-point to microwave radios,
amplifier, and other commercial applications.
AKON | akoninc.com
San Jose, CA
Microwave amplifiers 0.5 to 20.0 GHz, power
dividers and gain (slope) equalizers 1.0 to 18.0 GHz, converter
assemblies 2.0-20.0 GHz, filter banks and switch filter
banks 2.0-18.0 GHz, discriminators.
Amplitronix | amplitronix.com
| Costa Mesa, CA
Manufacturer of high quality RF and
IF Surface acoustic Wave (SAW) filters, resonators, and
Voltage Controlled Oscillators (VCO).
Anatech Electronics | anatechelectronics.com
973 772-4242 | Garfield, NJ
Focuses on the design and
manufacturing of RF and microwave filters and related products.
A broad array of products are employed in commercial, aerospace
and defense, and industrial applications throughout the
world. Products include bandpass, lowpass, highpass, and
bandstop filters, duplexers, diplexers, and triplexers,
in lumped element (LC), ceramic, cavity, crystal, SAW, and
antennas.us | antennas.us | 954-0975-2712
| Margate, FL
Antennas for military, mobile radio, GPS,
EMS, satellite/terrestrial, ISM, WLAN/Wi-Fi/WiMax, Ham,
AM/FM/satellite radio. Cable assembly, connectors, diplexers &
filters, software, measurement services.
AVX | avx.com
843-946-0414 | Myrtle
Capacitors, thin film directional couplers,
Z-chip combo R&C impedance matching surface mount chip,
ESD/surge protection, EMI/RFI feedthrough filters, AVX SPIMIC
capacitor calculation, connectors - PCB, rack-and-panel,
DIN, coaxial/RF, filters, resistors.
Bartley Machine & Manufacturing
978-388-0085 | Amesbury, MA
programmable active bandpass filters designed to eliminate
all adjacent channel interference in applications up to
2GHz. No insertion loss - programmable gain.
Bree Engineering | breeeng.com
| San Marcos, CA
Standard SMT packages, data link, low
profile surface mount LC, PCB Mounted LC, combline, non-reflective,
High power low-pass, image reject combline filters, GPS
diplexers, GPS diplex band splitters, highpass/lowpass diplexers,
Cernex | cernex.com
Amplifiers, antennas, couplers, isolators,
circulators, filters, diplexers, oscillators, noise sources,
switches, phase shifters, transition & adapters, mixers,
waveguide products, attenuators, terminations, detectors,
Channel Microwave | channelmicrowave.com
805-482-7280 | Camarillo, CA
Coaxial and waveguide
isolators, circulators, ISO-adapters, integrated assemblies,
Ciao Wireless | ciaowireless.com
| Camarillo, CA
Broad selection of amplifiers for multi-octave,
octave & ½-octave, broadband, LNAs, and RF limiting.
Replacement amplifiers for anything previously or currently
made by JCA Technology, Cougar (connectorized versions),
Avantek, WJ, CTT, Celeritek, Amplica, among others, but
at a much quicker delivery. Also manufacture radial combiners
and space qualified filters. Environmental screening services
ClearComm Technologies | clearcommtech.com
410-860-0500 | Salisbury, MD
Base station, delay filters
for feed-forward amps, diplexers, custom up to 40 GHz, waveguide
filter products 7-40GHz; cavity filter products include
transmit and receive filters as well as duplexers and multiplexers
covering the frequency range of 300 MHz to 6.0 GHz.
CMT Filters | cmtfilters.com
| Pollock Pines, CA
Cavity and waveguide filters, duplexers
and filter-based assemblies for the wireless, commercial
and military marketplaces.
Coilcraft | coilcraft.com
| Cary, IL
RF, power inductors, EMI/RFI filter products,
xDSL magnetics, transformers.
Coleman Microwave | colemanmw.com
800-563-3449 | Edinburg, VA
Diplexers, low pass, band
reject, band pass, waveguide, coaxial, high power, harmonic,
CommsAudit | commsaudit.com
225 3131 | Cheltenham, England
RF and digital equipment
and subsystems for Defence, Telecommunications, Military,
and broadcast communications applications. Frequency range
10 kHz to 60 GHz including digital control and digital signal
processing (DSP). COTS, quadrature I/Q Receivers, multi-channel
receiver systems, RF switching matrix, RF multicouplers,
antenna matrices & multicoupler distribution units,
masthead amplifiers, RF filters.
Continental Microwave & Tool (now
Cobham) | cobham.com
603-775-5200 | Exeter, NH
solid state switches, attenuators, microwave switch filter
assemblies, high power switches, PIN-diode control components,
and GaAs microwave devices, waveguide components, assemblies
and subsystems, integrated assemblies.
Corry Micronics | cormic.com
| Corry, PA
Dielectric resonators, bandpass filters,
LC filters, VCOs, PLLs, patch antennas, power dividers,
connectorized lumped element power dividers, directional
couplers, isolators/circulators, high power hybrids, diplexers &
multiplexers, attenuators, switches, cavity filters, waveguides,
standard gain horn antennas.
CTS Corporation | ctscorp.com
| Elkhart, IN
Bluetooth, ceramic duplexers, filters,
terminators, DIP switches, modules (synthesizer, frequency
translator, jitter attenuation, timing, clock generators,
VCO's, high frequency VCXO's, VCSO's, IF filters), oscillators.
Delta Microwave | deltamicrowave.com
805-240-1044 | Oxnard, CA
Filters, diplexers, multiplexers,
filter/amplifiers, variable attenuators, integrated assemblies,
power combiners, waveguides. Product frequencies from 1
kHz to 50 GHz with RF power handling up to 25 kW.
Eastern Wireless TeleComm, Inc | ewtfilters.com
410-749-3800 | Salisbury, MD
RF & Microwave filters,
duplexers, & multiplexers to 40 GHz for all commercial,
military, & wireless, applications.
Emicon Corporation | emiconcorp.com
915-590-0795 | El Paso, TX
Custom manufacturer of coils,
powerline filters, signal line filters, EMI filters, low
pass filters and inductors.
EMR Corporation | emrcorp.com
| Phoenix, AZ
RF peripherals devices from 30 MHz to 2.8
GHz. Design, manufacture and systems' engineering for RF
isolators, amplifiers & BDAs, filters - band pass &
band reject, mobile & base station duplexers, combiners
- cavity ferrite & hybrid ferrite, RX multicouplers
and accessories including LNAs.
EPCOS | epcos.com
800-689-3717 | Iselin,
Capacitors, SAW, inductors/EMC components, nonlinear
resistors, ferrite components, surge
Eyal Microwave Industry | eyal-emi.com
972-9-7493184 | Israel
PIN switches, diodes, high power
switches, limiters, power dividers, phase shifters, switched
bank filters, converters.
Filtek, Inc | filtek.com
| Tubac, AZ
Bandpass, lowpass, highpass and bandstop
filters, power dividers, filters, couplers and beam forming
Filtel | filtel.com
Couplers, power dividers, isolators, coaxial &
Filtronetics | filtro.net
| Kansas City, MO
Leading supplier of custom IF, RF,
Microwave, EMI(military) & Front End filters. Filter
types include LC, crystal ceramic, SAW & microwave from
DC to 10 GHz . Oscillators and crystals are available including
TCXOs & VCXOs. Filtronetics Inc has been providing solutions
to for 35 years and is ISO-9001:2000 certified.
Filtronic Solid State | (now Teledyne
Microwave) | teledynemicrowave.com
650-962-6944 | Mountain
Synthesizers, YIG filters & oscillators,
phase locked and free running DRO's, transceivers, converters,
ferrites, microwave integrated assemblies, BAW delay lines.
FSY Microwave | (now Spectrum Microwave)
888-553-7531 | Columbia, MD
RF & microwave filters to 40 GHz. LC | cavity | ceramic
| waveguide types. 20 years of design experience able to
meet your custom specification.
Guided Wave Technology | guidedwavetech.com
+45 20 88 58 30 | Denmark
Filter and Coupling Matrix
Synthesis Software. Get an overview of main filter parameters
in seconds, without complex circuit models and modeling.
Our Coupling Matrix Synthesis™ software facilitates synthesis
of N+2 coupling matrices for Chebyshev bandpass filtering
functions, with arbitrary finite-position transmission zeroes.
The software also facilitates coupling matrix synthesis
through topology matrix definition. It gives a fast and
accurate overview of insertion loss, isolation, group delay
and coupling coefficients versus filter order, return loss
and transmission zero positions. The software allows placement
of complex transmission zeroes, which opens up for group
delay shaping and analysis.
ILSI America | ilsiamerica.com
| Reno, NV
Frequency control products - crystals, data
clock oscillators, VCXO, VCO, TCXO, TCVCXO, OCXO, crystal
filter, saw filter synthesizers.
Integrated Microwave | imcsd.com
| San Diego, CA
Bandpass, highpass, lowpass filters,
Ion Beam Milling, Inc | ionbeammilling.com
603-644-2326 | Manchester, NH
Since 1982 has manufactured
thin film circuits for use in the microwave and photonics
industries. Dry etch ion beam milling process to ensure
a high level of repeatability. An array of standard products
are ready to ship and we can create custom circuits to match
your drawing. Ion Beam Milling also specializes in services.
We can offer photolithography, milling, and/or dicing services
to meet your needs. ISO 9001:2000 qualified.
Johanson Technology | johansontechnology.com
805-389-1166 | Camarillo, CA
LTCC chip antennas for
Bluetooth, WLAN, 2.45 GHz ISM band, ceramic filters, diplexers,
baluns, inductors, capacitors, couplers, laser trim, JTIsoft®
K&L Microwave | klmicrowave.com
410-749-2424 | Salisbury, MD
Filters, suspended substrates,
KDI-Triangle | (now Aeroflex-KDI) |
| Whippany, NJ
Aeroflex | KDI-IP filter products for
RF and Microwave filters are individual filter and multi-function
assemblies for wireless base station front ends, point-to-point
to microwave radios, amplifier, and other commercial applications.
These include cavity types with metal or ceramic resonators, &
printed filters such as bandpass, lowpass, bandreject, duplexer,
triplexer & multiplexer.
KMW | kmwinc.com
800-832-0569 | Cerritos,
AMBA (Active Multi Beam Antenna System), amplifiers,
arrestors, attenuators, combiner/dividers, connectors, couplers,
duplexers, filters, isolators/circulators, phase shifters.
KOA Speer Electronics | koaspeer.com
814-362-5536 | Bradford, PA
3-terminal EMI/RFI filters, circuit protection, inductors,
KR Electronics | krfilters.com
| Avenel, NJ
All standard filter types (lowpass, highpass,
bandpass, bandstop, equalizers, diplexers, duplexers, notch)
and individually synthesized filters for special applications.
State of the art computer synthesis, analysis and test methods
are used to meet the most challenging specifications for
military, commercial, medical, communication, radar, positive
train control (PTC), and navigation .
L-com Global Connectivity | l-com.com
800-341-5266 | North Andover, MA
Manufacturer of cable
assemblies, connectors, antennas, amplifiers, and other
and other connectivity devices
Lark Engineering | larkengineering.com
949-240-1233 | San Juan Capistrano, CA
bandpass filters, diplexers.
Linwave Technology Ltd | linwave.co.uk
+44 1522 681811 | Lincoln, UK
RF and microwave design
and manufacturing company with specialist knowledge in module
and sub-system design. Our experience encompasses the consumer,
industrial, automotive and defense market sectors. SATCOM
BUC, SSPA, Military microwave sub modules.
Lattice Semiconductor | latticesemi.com
503-268-8000 | Hillsboro, OR
FPGA, FPSC, CPLD, SPLD,
digital interconnects, programmable analog ICs, automotive
temperature devices, military devices, programmable logic
development tools, advanced packaging.
Lorch Microwave | lorch.com
| Salisbury, MD
Cavity, waveguide, discrete, tunable,
ceramic, wireless, tubular filters, integrated assemblies,
mixers, phase comparators, phase shifters.
LUXCONN Technology | luxconn.co.kr |
82-2-2026-7500 | Seoul, Korea
Manufactures RF connectors,
coaxial cable, and passive components including power splitters,
power dividers, directional couplers, surge arrestors, terminators,
Maruwa America | maruwa-g.com
| Torrance, CA
Ceramics capacitors, VCOs, resonators,
multilayer ceramic substrates (HTCC/LTCC), thin-film substrates,
Maxim Integrated Products | maxim-ic.com
800-998-9872 | Sunnyvale, CA
analog switches, multiplexers, analog filters, linear and
mixed-signal integrated circuits, power supplies, battery
management, RTCs, clocks, oscillators, delays, counters,
fiber optic ICs.
MCLI | mcli.com
800-333-6254 | St.
Power dividers, couplers, isolators, circulators,
waveguide components, oscillators, filters, hybrids, attenuators,
switches, terminations, amplifiers.
Mercury United Electronics | mercuryunited.com
909-466-0427 | Rancho Cucamonga, CA
Clock oscillators, VCXO, TCXO, OCXO, low EMI spread spectrum
clock oscillators, leaded and surface mount crystals, monolithic
crystal, leaded and surface mount filters, timing modules,
GPS frequency references.
MicroAxiom | microaxiom.com
| Poway, CA
Leading the way in filter innovation. Manufacture
of high power, cavity, combline, interdigital, lumped element,
LTCC modules, switches, amplifiers, switch filter banks,
and GPS modules.
MicroLab/FXR | microlab.fxr.com
| Livingston, NJ
Attenuators, bias tees, couplers, dc
blocks, coaxial junctions, terminations, low pass filters,
power splitters/dividers, tuners & line stretchers,
waveguide dummy loads.
Microwave Components and Systems, Inc
508-480-0106 | Marlboro, MA
a wide range of standard and custom waveguide and coaxial
components and systems including power combiners, filters,
multiplexers, pressure windows, terminations, couplers,
hybrids & transitions; custom designs, small quantities
available, quick delivery.
Microwave Filter Company, Inc | microwavefilter.com
800-448-1666 | East Syracuse, NY
1 MHz to 50 GHz, HP,
LP, BS, BR, multiplexer, tunable notch, high power, subminiature,
waveguide, microstrip, lumped element.
Microwavefilters | microwavefilters.it
| +39(0)292162703 | Pioltello, Milano, Italy
of RF components including waveguide band and channel filters,
duplexers, couplers, tapers, adapters, flanges, housings
and cold plates for RF bridges, and also offers offering
also electric testing, project consulting and problem solving.
Microwave Resources, Inc | microwaveresourcesinc.com
909-627-4125 | Chino, CA
Amplifiers, attenuators, circulators,
isolators, frequency multipliers, waveguide couplers, mixers,
detectors, filters, pin switches, adapters.
Mini-Circuits | minicircuits.com
Attenuators, baluns, bias tee, cables (test
quality), chokes, DC blocks, mixers, amplifiers, filters,
line stretchers, modulators, oscillators, power combiners
| couplers | splitters, switches, terminations, transformers.
Surface mount, connectorized. Application (app) notes.
MtronPTI | mtronpti.com
| Yankton, SD
Manufactures a complete range of frequency
control products for commercial and military applications,
including crystal resonators, OCXOs, TCXOs, VCXOs, monolithic
and discrete crystal filters, LC filters, and RF subassemblies.
Murata Electronics | murata.com
| Smyrna, GA
Chip multi-layer (1.0 2.5 GHz), chip dielectric
(2450 GHz, Bluetooth), surface mount capacitors, thermistors/resistors,
coil (inductors)/delay lines, noise suppression products/EMI
filters, resonators, piezoelectric sound components, coaxial
connectors, antenna/duplexers, isolators/circulators, PLL
modules, VCOs, TCXO, RF diode switches, DC-DC converters,
Narda Microwave East | nardamicrowave.com
Filters, isolators, power combiners, couplers, RF mechanical
switches and PIN diode switches.
Nortec RF | nortec-rf.com
| Mount Laurel, NJ
RF/microwave power combiners/dividers,
unidirectional and bidirectional couplers, hybrid couplers,
filters, and power amplifiers. New products added on regular
NTK Technologies | ntktech.com
| Santa Clara, CA
Packages - LTCC, LCC, CPGA, AlN, CGFP,
FP, side braze hybrid, thin film, flip chip, organic flip
chip, microwave. Ceramic directional couplers, filters,
diplexers, antennas, switch modules, resonators and ultrasonic
Omniyig | omniyig.com
| Santa Clara, CA
Manufacturer of band reject, bandpass
Yig filters, Yig oscillators and Yig multipliers with and
without integrated analog or digital drivers, comb generators
with and without integrated input power amplifiers, various
types of detectors and limiters.
Oscilent Corporation | oscilent.com
949-252-0522 | Irvine, CA
Oscillent refuses to pay
their final bill to RF Cafe.
Panasonic | panasonic.com
| Secaucus, NJ
Surface mount capacitors, directional
couplers, antenna switches, SAW filters, attenuators, power
dividers, duplexers, transformers, inductors, coils, batteries.
Picosecond Pulse Labs | picosecond.com
303-443-1249 | Boulder, CO
Amplifiers, drivers, attenuators,
baluns, transformers, bias tees, comb generators, custom
pulse generators, DC blocks, driver/controller modules,
ECL/PECL terminators, edge compressors, impulse forming
networks, low-pass filters, power dividers, pulse generators,
sampler modules TDR/TDT instruments.
Planar Monolithics Industries | pmi-rf.com
301-662-5019 | Frederick, MD
PMI designs, develops,
manufactures, tests, and markets hybrid RF/microwave and
monolithic integrated circuits (MIC/MMIC) and components
hybrid MIC/MMIC supercomponents and subsystems.
Pole Zero | polezero.com
| West Chester, OH
Modular digitally tuned RF filters
Q Microwave | qmicrowave.com
| El Cajon, CA
Custom & standard filters, integrated
microwave assemblies, design tools, lab support services.
Quasar Microwave Technology | (now The
Waveguide Solution) | waveguidesolution.co.uk
1626 835255 | UK
Flexible twistable and rigid waveguides,
flanges, pressure windows, power splitters, hot stand-by
couplers, filters, diplexers.
Ray Micro Devices | raymicrodevices.com
717- 266-8666 | York, PA
State-of-the-art and highly
scalable design and fabrication solutions for Microwave,
Telecom and Satellite Communications. RMD's expertise lies
in the development of hardware products for the 10-40 GHz
RF Microwave Design Ltd | rfmicrowavedesign.com
+44 (0)1626 835269 | UK
Custom, semi-custom and standard
passive microwave components. Diplexers, filters and antennas
designed and tested. A complete design, development and
validation service to the RF and microwave industry.
RF Monolithics, Inc. - RFM | rfm.com
800-704-6079 | Dallas, TX
Offers a broad range of wireless
solutions, from comprehensive industrial wireless sensor
networks to high performance RF components including SAW
resonators, narrow band filters, RF and IF filters, oscillators,
clocks & crystals, RFIC and SAW based radios, RF modules
and standalone radios, M2M.
RLC Electronics | rlcelectronics.com
914-241-1334 | Mount Kisco, NY
Filters, couplers, coaxial
switches, attenuators, power dividers, terminations, bias
tees, DC blocks.
RS Microwave | rsmicro.com
| Butler, NJ
Filters, multiplexers, subassemblies.
RTx Technology Co., Ltd | rtxtech.com
+82-31-743-6275 | South Korea
Filters, duplexers, multiplexers
(ceramic/cavity), VCOs & PLL synthesizers, isolators &
circulators, up/down converters, combiners & dividers,
directional couplers, SAW devices, attenuators, terminators.
Sage Labs - Filtronic | (now Spectrum
Microwave) | spectrummicrowave.com/default.asp
0844 | Natick, MA
Power dividers, couplers, hybrids,
filters, rotary joints, mixers, phase shifters.
Salisbury Engineering | (now Spectrum
Microwave) | spectrummicrowave.com
888-553-7531 | Delmar,
Custom integrated microwave assemblies, tuners, synthesizers,
filters, reference oscillators, harmonic generators. Call
to discuss with an engineer your microwave component or
Samsung Electro Mechanics | sem.samsung.com
408-544-5262 | San Jose, CA
Ceramic filters for base
stations, repeater from 400 MHz to 5 GHz. Saw filters, VCOs,
Sawtek | (now a division of TriQuint
Semiconductor) | triquint.com
407-886-8860 | Apopka, FL
RF, IF filters, duplexers, base stations, wireless LAN.
Spectrum Control, Inc | spectrumcontrol.com
866-281-0989 | Fairview, PA
Connectors - circular, D-subminiature,
DIN, terminal blocks, plugs and jacks, coaxial/RF. EMI/RFI
filtered feedthrough connectors
Syfer Technology | syfer.com
723300 | Norfolk, Suffolk, England
Syfer has 25+
years experience in manufacturing ceramic capacitors, both
SMD and thru-hole EMI filters and EMI Power Filters.
Tai-Saw Technology | taisaw.com
RF, IF, crystal filters, SAW filters, crystal
resonators, crystal oscillators, VCOs, TCXOs.
TDK | tdk.com
516-535-2600 | Garden
Filters, multi-layer ceramic capacitors, inductors,
EMC components, LAN components, ferrite cores, amorphous
cores, transformers, magnets, magnet applied products, piezoeletronic
products, delay lines, sensors, power supply, RF components,
RF modules, and more.
Teledyne KW Microwave | teledynekwmicrowave.com
858-842-2993 | Poway, CA Filters, multiplexers, diplexers,
multipliers, solid state switches, switch filters, low noise
amplifiers, preamplifiers, coaxial switches, ferrite circulators
and isolators, integrated subsystems covering the frequency
range 5 MHz to 40 GHz.
TELSA | telsasrl.it | +390354876000
| Osio sotto (BG) Italy
Basestation antennas, combiners,
couplers, circulators, filters, duplexers, power splitters
and components for the air traffic control, private mobile
radio, cellular, wireless communications and tactical markets.
Tiger Micro-Electronics Institute |
510-635-4270 | Oakland, CA
power divider/combiners, mixers, modulators, switches, isolators,
circulators, phase shifters.
Token Passive Components | token.com.tw
| +886-2-2981 0109 | Taiwan
Ceramic resonators, filters,
dielectric patch antennas, resistors.
Toko America | tokoam.comv847-297-0070
| Mt. Prospect, IL
Filters, baluns, inductors, antennas,
semiconductors, amplifiers, A/D converters.
Trans-Tech | trans-techinc.com
| Adamstown, MD
Resonators, bandpass filters, garnets,
ferrites, dielectrics, substrates.
Trilithic | trilithic.com
| Indianapolis, IN
Attenuators, filters, switches, terminations,
emergency alert systems.
Triquint Semiconductor | triquint.com
503-615-9000 | Hillsboro, OR
Wireless, telecom and
millimeter amplifiers, GaAs integrated circuits and transistors.
TTE | tte.com
800-776-7614 | Los Angeles,
Bandpass, lowpass, highpass filters, diplexers, multiplexers,
cases, balun, isolation & matching transformers.
Tusonix | tusonix.com
| Tucson, AZ
EMI/RFI filters, surface mount EMI filters,
variable trimmer capacitors, filtered terminal blocks, custom
EMI filter plate assemblies, ceramic disc capacitors.
Ultra-Crea Oy | ultra-crea.fi | +358
50 444 9100 | Finland
Specializes in the design, development
and manufacture of custom designed/specialty antennas and
RF filters from 10 MHz to 6 GHz.
US Microwaves | usmicrowaves.com
| Santa Clara, CA
Supplies custom and standard microwave
thin film circuits, thin film components and semiconductors
for analog and digital multi-chip module circuits, medical,
military and commercial RF & microwave, fiber optic
and optoelectronics, satellite, video and wireless communication
UTE Microwave, Inc | utemicrowave.com
732-922-1009 | Asbury Park, NJ
Vanlong Technology | vanlong.com
| Rochester, WI
SAW resonators, SAW filters, ceramic
Vectron International | vectron.com
888-328-7661 | Hudson, NH
Crystals, oscillators, SAW
Ventronics USA | ventronicsinc.com
908-272-9262 | Kenilworth, NJ
Resistors, varistors, thermistors,
diodes, rectifiers, quartz crystals, oscillators, filters,
switches, coils, EMI filters, microcircuits, capacitors,
battery packs, inductors, batteries, transformers, LED/LCD,
line cords, piezoelectric devices, cable assemblies, relays,
blowers, fans, power supplies, thermal cutoffs, PCBs, potentiometers,
delay lines, transducers, chokes.
Wainwright Instruments | wainwright-filters.com
+49 (0) 8152-918230 | Germany
Lowpass, highpass, bandpass,
notch filters, diplexers & multiplexers.
Ye Eun Tech | yeeuntech.com
| Gunpo, Kyunggi, Korea
Coaxial (RF) cable assemblies,
adapters, filters, power splitters, and multiplexers.