Gamma Instruments

Call: (585) 234-1710 Address: 5077 Old Bald Hill Road, Hemlock, NY 14466
Fax: (585) 367-9659 Email: gammainstruments at frontiernet.net

SPECIAL SALE!!! - SERVICE MONITORS FOR ONLY $2400.00? - SEE BELOW!!!
This is Gamma Instruments. We buy, sell, and service used Spectrum Analyzers, Network Analyzers, Service Monitors, Power Meters, Signal Generators and other used RF Test Equipment manufactured by Agilent, Hewlett Packard, Anritsu, Motorola, IFR, Marconi, Tektronix, Fluke, Gigatronics, and more.

Buying used and refurbished test equipment from us can save you up to 70% or more off the manufacturer's list price. We offer a 5-day Right-of-Refusal and 180-day full parts and labor warranty on most equipment. Also, if you have excess test equipment that you would like to sell, let us help you liquidate it. We're very competitive and we offer cash, usually within 48 hours!

Gamma Instruments accepts payment from MasterCard and Visa credit cards, bank checks, and personal checks.
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Used Test Equipment For Sale

Spectrum Analyzers:

Network Analyzers:

HP 8753C: Vector Network Analyzer, 300kHz – 3 GHz, for measurement of reflection and transmission parameters when used with an HP 85044A transmission/reflection test set, or measurement of scattering parameters when interfaced to an S-parameter test set (such as HP 85046A or HP 85047A). Two independent display channels can simultaneously display reflection and transmission parameters, phase, magnitude, and group delay of active and passive RF networks. Unit contains built-in precision synthesized RF source and a dual channel three-input receiver. Large Color CRT displays measurements of one or two parameters in rectangular, polar, or Smith Chart formats. This used HP 8753C comes with factory-installed option 010 (Time Domain Operation) which generates the inverse FFT to display the time domain response of networks. With option 010 the HP8753C can measure the impulse response of RF networks, as well as simulate a Time Domain Reflectometer (TDR) and display responses of networks as a function of time or distance (TDRs are good for transmission line fault diagnosis and location). Digital Signal Processing (DSP) makes for easy calibration, full two-port vector error correction, measurement, and displays. Built-in microproccesor control enables easy selection of measurements, calibration sequences, and save/recall of four analyzer setups and up to six automated test sequences (sequence position 6 is stored in non-volatile memory and will survive without line power). HP-IB bus for output of measurement results straight to a compatible printer, storage of instrument states to a compatible disk drive, or complete system automation with the addition of a HP200/300 series computer. This HP 8753 C has been thoroughly tested and proven to be in excellent working condition. It comes with option 010 and a 5-day Right-of-Refusal.

HP 8753C with opt. 010 (picture).........JUST REDUCED AGAIN !!!...........$5900.00 SOLD

HP 8753C with opt. 010 PLUS HP 85046A (picture).....JUST REDUCED AGAIN!!! .....$8700.00 SOLD

Communications Service Monitors:

Want a great bench top Service Monitor for $2400? Look at the HP 8924C below. We have units with the 60 WATT INPUT! These will do everything an HP 8920A or 8920B will do and include a spectrum analyzer / tracking generator.

Click here to see the HP8924C's at the AMTRONIX INSTRUMENTS website!
The HP 8924C (above)

HP 8920A: is a full-feature, one-box RF Communications Test Set designed to meet the communications test needs of both service and manufacturing environments. Combining up to 22 complete instruments, the HP8920 A offers the full functionality needed in testing land mobile radios, cellular phones, and communications systems. The HP 8920 A allows you to replace several individual instruments with one. The Standard Features of the HP 8920A are: 250 kHz - 1GHz AM/FM Signal Generator; AM/FM Modulation Analyzer; Duplex Offset Generator; RF Power Meter; 400 kHz - 1 GHz RF Frequency Counter/Frequency Error Meter; SSB Demodulator; Audio Frequency Counter; AF Power Meter; AC/DC Voltmeter; SINAD/SNR Distortion Meter; Two Variable AF Generators; Digital Oscilloscope; Built-in I-BASIC Controller; 2uV sensitivity (typically <1uV). These refurbished units are fully calibrated and come with a 5-day Right-of-Refusal and a 180-day full parts and labor warranty.

HP 8920A with opt 002, 003, 004, 005 ......... $4500.00
HP 8920A with opt 001, 002, 003, 004, 005, 050 (picture) .......... $4900.00
HP 8920A with opt 001, 004, 013, 014, 050, 102, 103 SOLD............ $6500.00
(HP 8920A optional feature descriptions)

HP 8920B:

HP 8920B with opt 001, 004, 051, 102 with 5-day ROR and 180-day full parts and labor warranty........ $6500.00

Service Monitor Self-Tests vs. Built-In Diagnostics, and Listing the Installed Options

When you first turn on your unit, it will automatically run a self-test program and the screen should indicate:"All self tests pass". This message indicates that the power supply voltages are correct and that there are no major failures. It is not an absolute indication that the unit is working properly.

However, you can run the built-in diagnostic program in your HP8920A, HP8920B, HP8921A and 8924E/C units. This is a more complete test of your unit for faults. Click the link below for detailed instructions.

How to Run Built-In Diagnostics and List the Installed Options

Do You Want Used Guaranteed Parts for Agilent / HP / IFR /Motorola Service Monitors?

Used Guaranteed Parts for Agilent / HP 8920 A/B, 8921A, 8922, 8924 C/E, E6380A
Motorola R2200 A/B
IFR COM 120B
and Others

Click here to see the parts for sale at the AMTRONIX INSTRUMENTS website

RF Power Meters and Measuring Receivers:

HP 8902A Measuring Receiver: This functions as a high linearity, high accuracy and resolution RF Power Meter and Modulation Analyzer for the frequencies 150 kHz to 1.3 GHz and power levels from +30 dBm to –127 dBm (using its built-in tuned 2.5 MHz to 1.3 GHz RF receiver with IF synchronous detector). The 8902 can display power or voltage readings in Watts, dBm, dBr, %r, volts, mV, uV, dB V, dB mV, or dB uV. It also is able to measure AM, FM, and Phase Modulation. The 8902A has 5 different types of AM, FM, and PM detectors (+peak, -peak, +/- peak/2, peak hold, rms, and average(rms sinewave calibrated) ) that delivers an ultra-low distortion demodulated output to the Modulation Out/Audio In connector. The built-in 50 MHz 1.0 mW power reference standard is accurate to 0.7% traceable to NIST. The 8902A receiver’s internal Frequency Counter has a range of 150 kHz to 1.3 GHz and a sensitivity of –25 dBm for 150 kHz to 650 MHz, and –20 dBm for 650 MHz to 1.3 GHz. It’s resolution is 1 Hz maximum with a worst case accuracy of 30 Hz. Additional features include Frequency Error (measures delta frequency between the keypad entry and RF input), Power delta, AM, FM, PM, automatic RF tuning and tracking, Audio Generator, Front and Rear Panel Inputs and Outputs for HP-IB, AM, FM, Recorder, and IF outputs, 10 MHz Time Base Input, LO In and Out, Remote Cntl RF Swiches, and Freq Offset TTL Out, Audio Filters, and Audio Frequency Counter. Two tables of frequency/cal factors (for using 11722A, or 11792A Sensor Modules) can be stored in the internal non-volatile RAM. This used HP 8902A has installed options 030, 033, and 037 (Carrier Noise Measurements ). This 8902A had a calibration sticker on it that expired 4/29/07. It has been extensively tested and measurements show it to be fully operational and in calibration. The 8902A comes with a 90-day parts and labor warranty and a 5-day Right-of-Refusal.

HP 8902A with opt 030, 033, 037(picture).............. $ 6,700.00 SOLD

Signal Generators:

HP 8657A RF Synthesized Signal Generator: covers 100 kHz to 1040 MHz, 10-Hz resolution, from +12 to -143.5 dBm with +/- 1dB resolution, has built-in electronic attenuator, 0-99% AM and up to 99 kHz FM peak deviation, internal and external modulation, combined AM/FM modulation, AC or DC-coupled FM, 1-degree carrier phase adjust feature, and memory storage, recall, and sequence registers for up to 100 front panel setups that can be accessed or sequenced from the front panel or the rear panel SEQ port. This used HP8657A RF signal generator has been extensively tested and appears to still be in calibration. The 8657A external case has some cosmetic wear, but nothing major. The front panel is clean and all the LEDs are in excellent condition. It comes with Option 001 (the built-in high-stability frequency reference), rear-panel HP-IB/GPIB bus I/F, and Option 909 (the combined Front Handles and Rack Flange Mounts), and a 5-Day Right-of-Refusal.

HP 8657A with opt 001, 909 ...(pictures)..... ....... $850.00

Wavetek Model 171: Synthesizer/Function Generator provides sine, triangle, square wave, and DC output functions from both 50-Ohm and 600-Ohm outputs. Also has TTL pulse and 1 MHz pulse reference outputs, a DC offset control, Two modes of frequency control (either a continuously variable analog dial, or a 4 1/2 digit thumbwheel switch synthesizer), an input connector for external frequency reference. The Wavetek 171 can do frequency sweeping and frequency tracking. Output level is continuously variable over an 80 dB range with step and vernier controls. Up to 10 Volts peak-to-peak output for the sine, triangle, and square waves into matched terminations. Frequency range with the continuously variable dial: 0.1 Hz to 2 MHz, accuracy: 3% of full scale. Frequency range with the synthesizer: 1 Hz to 2 MHz, resolution: 0.001 Hz on the lowest decade range, and 100 Hz on the highest range. All output and input connectors are front-panel-mounted. Although the cal sticker on this unit has expired, this used Wavetek 171 has been fully tested, appears to be in cal, and is in excellent working order. Unit comes with a CD Operating and Service manual, and 5-day Right-of-Refusal.

Wavetek Model 171 (picture)......JUST REDUCED AGAIN!!!.....$275.00 SOLD

Stanford Research Systems DS335: a DDS Synthesized 3 MHz Function Generator with sine and square (up to 3.1 MHz), ramp and triangle (up to 10 kHz), and 3.5 MHz Gaussian white noise functions. The DS 335 has 50 Ohm output, can sweep linearly or logarithmically in phase-continuous fashion over their frequency ranges, has a Sweep sync output, and can sweep unidirectional or bidirectional. It also has internal and external FSK modulation modes for frequency toggling, both GPIB and RS-232 interfaces (option 01), and a non-volatile memory for storage/recall of up to 9 sets of front-panel set-ups. The cal has expired, but this used DS335 has been fully tested and appears to be in cal. It's case is slightly scratched and is missing its feet, but is otherwise in excellent working order. This unit comes with a 5-day Right-of-Refusal.

DS-335...(picture)....................... $450.00

HP 3336C Synthesizer/Level Generator: with opt. 907 (front handle assy.); it has 50 Ohm and 75 Ohm unbalanced (front panel BNC) outputs, frequency range of 10 Hz to 20.999 999 999 MHz with 1 µHz resolution for frequencies below 100 kHz and 1 mHz for frequencies greater than or equal to 100 kHz. Amplitude range at 50 Ohms output is -71.23 to +8.76 dBm; for 75 Ohms -72.99 to +7.00 dBm. The HP 3336C is renowned for its low phase noise and jitter, 11-digits of frequency resolution, precision output levels with 0.01 dBm resolution and 0.1 dB flatness, and low harmonic and spurious distortion. The 3336C features alpha-numeric data entry, selectable Fast or Slow amplitude leveling, amplitude blanking, selectable Hi-Res (0.1 deg) phase offset, programmable log/lin phase continuous frequency sweeping, programmable Marker Output, external phase and amplitude modulation, storage/recall of 10 instrument setups, and HP-IB control. The HP3336C has numerous rear-panel auxiliary outputs including Marker TTL output, SYNC out, 1 MHz 0dBm Reference out, and Aux 21 MHz to 60.999 999 999 MHz at 0dBm output. Auxialiary inputs include Ext Reference In (for phase locking to external frequency reference), amplitude and phase modulation inputs, and External Leveling input. The cal sticker on this unit has expired, but tests show that this 3336C is fully operational and appears to be in spec. This HP 3336C comes with opt. 907, plus a 5-Day Right-of-Refusal.

HP 3336C...(picture) ............... $375.00