16.9Other Accuracy Considerations –Always use averaging if a level measurement is rapidly changing its level like when measuring a radio carrier subjected to selective fading or SSB signals. This will give representative average readings over a two second periods and make it easier on your eyes by preventing racking of the display levels.

As discussed earlier, using the 10db measuring range will yield the greatest precision of .01db were the 100db range would have a lower precision of .1db. I have found on the air measurement of fading radio signals will loose accuracy with the 10db automatic level mode with averaging on caused by constant automatic measuring limit changes. The 100db range works much better for this and the .1db resolution is still much greater than needed for measuring rapidly varying radio signals.

Automatic selection of a range’s upper limit will usually result in the most optimum selection for best level measuring accuracy. However when tuning varying signals or different signals on a band, especially when in the 10db range, using the entry manual limit setting option, the entry selection method will stop constant auto ranging and resulting reduction in audio quality when fine tuning SSB signals. This and its reason is fully discussed in Chapters 2 and 4, sections 2.2 and 4.11.

For maximum level measurement accuracy auto cal should always be on. However in some special cases like when using the instrument’s tracking oscillator as a VFO to drive a transmitter, during the auto cal cycle there will be around a 100Hz frequency shift up and down in the frequency of the tracking oscillator. Then it’s best to leave auto cal off during transmissions but be sure to turn it’s on when changing frequency or making level measurements for maximum accuracy. Also turn off auto cal when tuning or monitoring the audio from a SSB signal since the SSB demodulation will be turned off during auto cal cycles.

16.10Using a HP3586 as a Signal Generator – After studying Chapter 14 on network analysis, you should realize this instrument can be used as a audio or RF signal generator by using it’s 75 ohm 1 miliwatt output from the Fo connector on it’s back panel. When it’s front panel is reading frequency with its CENTER annunciator on this frequency is always exactly that of the signal from the Fo connector. With a set of outboard 50 ohm attenuators and a 150ohm resistor in parallel with its Fo output, you can accurately adjust the output from nearly 0dbm down as low as the capability of your attenuators. The attenuators don’t even have to be accurate since you can calibrate their output signal using your HP3586’s level detector.

16.11Using a HP3586 to Receive and also Control a Transmitter – Here is an interesting idea some of you may want to explore on how to use a HP3586A or B to operate transceive with an AM transmitter. You could use the HP3586 as a SSB or AM receiver when controlling an AM transmitter’s carrier. Each time you transmitted you would have to be in the low distortion selective measuring mode with the speaker muted by turning down its volume. Then change to the noise/demodulation mode and turned up the speaker volume to receive the other station. This could be cumbersome having to remember to turn up or down the speaker and change mode each time you transmitted or received and if you forgot to change modes for transmitting while working a SSB station, get the other SSB station real mad at you. See section 10.3 of Chapter 10 and section 16.5 of this chapter to help understand how this would work.

You could also receive and tune the side band of an AM station the same way using the noise/demodulation mode, then use the low distortion mode only while sending to move the Fo output to the other AM stations carrier frequency. You could even use low distortion and the counter to first exactly determine the other AM station’s carrier frequency and to transmit, and then use noise/demodulation only to receive

Possibly the instrument could be modified to do this automatically using a computer or other device and placing it into remote control. On HP3586’s back panel is the HP-1B connector for remote computer control of the instrument that could possibly be used for this control function. To understand this connector’s function you’ll need a copy of the instrument’s technical and service manual.

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HP B, C, 3586A manual

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.