12.MEASURING IMPULSE NOISE

12.1General – During our wideband noise example we noticed some level changes indicating possible shot noise from some IC’s, a common problem with many inexpensive consumer solid state IC chips. In this chapter we will use the impulse measuring mode to test the shot noise from these chips and illustrate the use of this measuring mode. Unfortunately, the HP3586C doesn’t have this SSB channel mode and it can’t be simulated by any other mode so we can’t do this measurement with a C version instrument.

In this mode the instrument will output the number of pulses during a preset time that exceed a preset amplitude level.

12.2Setup – Since the frequency display will be used for counting pluses in the impulse mode, enter the filter’s center frequency before entering the impulse measurement mode. Press [FREQ] then enter 5.000 on the keyboard followed by pressing [KHZ]. Press [AUTO] on the measure/entry sub panel.

Press [SHIFT] on the measurement mode sub panel to select the impulse mode button. Press [IMPULSE] to place the instrument into the impulse measurement mode. Now press [OFFSET] on the measurement/entry sub panel to turn off the offset calculation if its button’s light is on.

We’ll arbitrarily decide to measure any noise pulse above –35dbm. Press [USB] or [LSB] to activate either one of the SSB channels, for this test either will work fine. Be sure the widest filter without WTD is selected and set its center frequency at 5KHz midway in our amplifier’s audio pass band. Next set an interval measuring time of 5 minutes and 30 seconds and a minimum pulse threshold of -35dbm. On the entry keyboard press [TIME] and enter 5.30 on the keyboard followed by pressing [MIN]. Next press [THSHLD] followed by 35 on the keyboard, then press [-db] and [MEAS CONT].

12.3Taking Measurements – Now install one of the IC’s we want to test into our audio amplifier. Start the test by pressing [START] on the measurement mode sub panel. After our 5 minute 30 second time interval we should see the number of shot noise pulses that exceeded our maximum noise level of – 35dbm on the RH side of the frequency display on the frequency/entry sub panel.

We can now compare the shot noise performance of our amplifier by the number of pulses over the time interval using different chips. This example is not especially the best way to measure shot noise in IC’s but chosen only to illustrate how the HP3586’s impulse measurement mode works and could be used.

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HP B, C, 3586A manual Measuring Impulse Noise
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B, 3586A, C specifications

The HP C3586A and C3586B tape drives are notable components in the realm of data storage solutions, primarily designed for enterprise-class environments. These SCSI (Small Computer System Interface) tape drives are regarded for their efficiency, reliability, and capacity to meet the growing demands of data backup and archival processes in businesses.

The C3586A model utilizes the DAT (Digital Audio Tape) technology, which allows it to deliver high performance and high data density. It features a native capacity of 2.3 GB per cartridge, which can be extended to 4.6 GB with the use of compression. This is particularly advantageous for businesses requiring significant amounts of data storage without the necessity for multiple tapes. The transfer rate is rated at up to 12 MB per minute, which ensures quick backups and restores, minimizing the operational downtime.

In terms of data integrity and security, both models incorporate advanced error correction techniques to guarantee that data remains pristine and intact throughout the storage duration. They are designed to work seamlessly with a variety of operating systems and backup applications, enhancing compatibility and user convenience.

The HP C3586B, on the other hand, offers similar foundational technologies but with enhanced features. It supports higher capacity tapes and is engineered to work seamlessly in high-performance environments. With the integration of SCSI-2 interfacing, users can expect faster data transfer rates, which is critical for organizations dealing with large volumes of data.

Another key aspect of both models is their rugged design, which provides durability and reliability needed for long-term storage solutions. The drives are built to withstand extended usage, which makes them a cost-effective choice for businesses looking to invest in dependable data storage systems.

Furthermore, these drives come with a user-friendly interface and straightforward maintenance. This allows IT personnel to handle backups with ease while keeping the workflow uninterrupted.

In summary, the HP C3586A and C3586B tape drives epitomize the union of technology, usability, and dependability. Their robust features, including high data capacity, fast transfer rates, and durable construction, make them a formidable choice for enterprises seeking efficient data backup and archival solutions in the ever-evolving digital landscape.
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