gsk@idx.com (02/04/91)
Can anyone pass on any information of the HP 581B (or was it 531B) spectrum analyzer display unit. (I'm sorry, it is at home, and my memory is having parity errors!)... The unit seems to have a BNC connector on the read marked "IF in". The unit itself seems to work (I get a base line, and can induce a few deflections with a signal generator).. It has a 5" crt, and bandwidth switches as well as an IF gain control. My questions are: What is the center of the IF expected for this unit, and would the unit itself serve as a panadaptor type display unit (spectral display about the IF center frequency) without additional equipment on a Shortwave radio with suitable IF frequency and bandwidth? And, what are the other items of the Spectrum Analyzer to which this belongs? I assume that there is a companion unit (with plug-ins?) which act as a "reciever" of the signal to be analized? I have stumbled into one of these at an exceedingly reasonable price, and may be able to acquire more, and am trying to find a use for them.. However, if they won't do what I want, then any price is too much! (B->)! Thanks for any help you can pass on.... -- -- George -- ------------------------------------------------------------------ - George Kaczowka IDX Corp Marlboro, MA - gsk@ziggy.idx.com - ------------------------------------------------------------------
gsk@idx.com (02/05/91)
After further examination, I have some corrections and amplifications... In article <2230.27ad7857@idx.com>, gsk@idx.com writes: > Can anyone pass on any information of the HP 581B (or was it 531B) spectrum > analyzer display unit. (I'm sorry, it is at home, and my memory is having > parity errors!)... **** It must have been worse than that!... The model # was '851B'. > My questions are: > What is the center of the IF expected for this unit, and would the unit > itself serve as a panadaptor type display unit (spectral display about the IF > center frequency) without additional equipment on a Shortwave radio with > suitable IF frequency and bandwidth? After looking a bit closer.. Is the IF input at 20mhz? I assume that I need to add a swept local osc. in synch with the display sweep, and mixer, etc... Am I on the right track? > I assume that there is a companion unit (with plug-ins?) which act as a > "reciever" of the signal to be analized? Does anyone know the # of this?? (maybe 851A?) Thanks again... sorry for so much wrong info on the first post... It must of been the excitement of stumbling into a "find"... (B->)... ------------------------------------------------------------ - George Kaczowka IDX Corp Marlboro, MA - gsk@idx.com - ------------------------------------------------------------
frankb@hpsad.HP.COM (Frank Ball) (02/08/91)
>From: gsk@idx.com Date: Mon, 4 Feb 1991 15:05:58 GMT Date-Received: Thu, 7 Feb 1991 01:45:43 GMT Subject: HP Spectrum Analyzer Display Info needed.. HELP? Organization: IDX Corporation, S. Burlington, VT Newsgroups: sci.electronics ------------------------------------------------------------------ - George Kaczowka IDX Corp Marlboro, MA - gsk@ziggy.idx.com - ------------------------------------------------------------------ **** It must have been worse than that!... The model # was '851B'. > My questions are: > What is the center of the IF expected for this unit, and would the unit > itself serve as a panadaptor type display unit (spectral display about the IF > center frequency) without additional equipment on a Shortwave radio with > suitable IF frequency and bandwidth? *After looking a bit closer.. Is the IF input at 20mhz? I assume that I need *to add a swept local osc. in synch with the display sweep, and mixer, etc... *Am I on the right track? There are three "frontend" modules for this display: 8557 .01-350MHz, 8558 .1-1500MHz, 8559 .01-21 GHz. They also fit the older 180-2 analog displays. None of these are made anymore. Surplus prices vary, but 8558s and 8559s usually aren't cheap. Often in the $thousands range. The 851 has a digital display. There is also an old Network analyzer module (the 8755 scaler network analyzer) that can be made to work with some modifications (change the sweep ramp from 0-10V to -5-+5V). It requires an external sweeper and the appropriate detectors for the frequency range. The IF is centered at 21.4 MHz, but the modules had detectors and video filters in them. They output video to the display. The spectrum analyzer modules also had vertical and horzontal amps in them. The display you have is only the power supply, and some digital hardware to digitize the video signal and put it on the CRT. I don't know what the 21.4 MHz input to the display was used for. Essentually what you have is an X vs. Y oscilloscope with a digital memory, but it is only designed to sweep left to right, one display point per horizonatal point, and a modest maximum sweep speed. If you have some other specific questions I might be able to help. Frank Ball 2LR-O frankb@hpsad.hp.com Hewlett Packard 1212 Valley House Drive (707) 794-4168 work Rohnert Park CA 94928-4999 I'm the NRA.