Power dbm = 10 log (Power in watts/.001)

or Power watts = .001 [ anti log ( power dbm/10) ]

Voltage dbv = 20 log (Voltage volts/Vr) or

Voltage volts = Vr [anti log (Voltage volts/20)]

Vr = .775 volts for the A and B models: Vr = 1 volts or .775 volts can be selected on the C model.

For optimum accuracy the instrument takes measurements over a small part of it’s total –120dbm to +20dbm measuring range by using a range selectable detector circuit. The selectable ranges are, 100db and 10db and have resolutions of .1db and .01db respectively. The readings are accurate over the whole 10db range but are only accurate over the upper 80db of the 100db range. The location of a range within the instruments total measuring range is operator or automatically selected for best level measurement accuracy. This is done by using an IF amplifier circuit whose gain is accurately changed. The IF amp is located just before the detector and changes its gain to select the upper limit for the range of values the detector is measuring. Specifying an upper limit for a range using the entry command actually selects the gain of the IF amplifier. Automatic limit selection is done using a circuit similar to the AGC circuit in a radio receiver.

One important point to remember is that the upper limit for the 100db range can not be set below –45dbm because –80db below this setting starts to equal the instrument’s noise floor of around –120dbm. When the detector is set to the 10db range the upper limit can be set much lower to –120dbm. The SSB demodulator receives its signal from the IF strip in parallel with the level detector and will only be able to demodulate signals above –55dbm. When the instrument is in the 100db range the gain of the IF strip is too low to read radio signals below this level. Therefore, when using the SSB detector for audio tuning of received radio signals we should almost always have the instrument in the 10db range since these radio signals are usually below –55dbm. In chapter 4 we’ll show how to work around this problem when receiving SSB signals.

For those of us working on electronic circuits or taking radio signal measurements this instrument is a valuable tool that can be used to measure RF or audio noise, the frequency of a received carrier, find and measure spurious transmitter signals, provide a signal and detector system for circuit analysis, and as a VFO to control the carrier of a transmitter. It will work as a SSB receiver over its whole frequency range to tune on the air signals for measurement. It receives and accurately measures signals down to -100dbm, which is much lower than the noise on most ham bands.

One disadvantage when receiving SSB signals is that the HP3586 will not output the actual carrier frequency of a SSB signal to its rear panel Fo output when using the SSB detector. It only outputs the center frequency of the selected band pass. In this document I will describe how to work around this problem when controlling AM transmitters.

2.3Instrument Accuracy - The instrument uses 100db or 10db changeable ranges for maximum accuracy as described above. The 100db range is only accurate over its upper 80db portion and has a resolution of .1db. In the automatic range limit control mode the 100db range will have its upper limit automatically changed to always stay within the accurate upper 80db part of this range. The narrower range of 10db has a resolution of .01db. The instrument’s level measuring frequency range is 200Hz to 32MHz with a frequency resolution of .1Hz and accuracy of + or - .000001 of it’s reading during the first year after calibration. The 004 optional crystal frequency reference was offered for greater frequency display accuracy, see Chapter 16, section 16.8 if your instrument doesn’t have this option.

The instrument is intended for accurate measurements only in the range of –100dbm up to +20dbm. Using the 50 or 75 ohm input from 200Hz to 32MHz and for signal levels between +20dbm and –80dbm, between –80db and –100db its accuracy is +/- .75dbm. From 200Hz to 200KHz and from +20dbm to – 80dbm its level accuracy drops to +/-.40dbm, and from –80dbm to –100dbm it’s +/-.95dbm. Below 100dbm it’s accuracy isn’t rated and level measurements below –100dbm should not be trusted even though the instrument will appear to read down to its noise floor of around –120dbm. By using

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HP 3586A, B, C 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.