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Re: HP AN/USM 281A Oscilliscope needs repair (San Antonio TX)
One last question for the night. Is there a component failure that would cause the beam/dot not to show on the screen when I apply low voltage to the test leads (1.5v battery) I have to hold the TEST
By Andrew Maich <andremajic@...> · #86142 ·
Re: HP AN/USM 281A Oscilliscope needs repair (San Antonio TX)
Cool. Thank you for the tip on where to check. I'm still trying to figure out if there are any settings I need to try without cracking the case open. I'll save this email for reference when I open it
By Andrew Maich <andremajic@...> · #86141 ·
Re: HP AN/USM 281A Oscilliscope needs repair (San Antonio TX)
Thanks for the help. What can I use for a signal? I don't have a signal generator. I tried testing it with a 3v 800ma wall wart using the EXT INPUT and didn't get a dot or anything. I tried using a
By Andrew Maich <andremajic@...> · #86140 ·
Re: Frequency calibration?
Unless there is a reason for extreme precision in your frequency measuring, you don't need to spend too much money adjusting the oscillator to a reasonable precision. The old method using WWV with a
By Stuart Landau · #86139 ·
Re: [TekScopes] Fast Rise/Fall Time Pulser
Mine arrived today. Alas, it uses a USB B connector instead of a more common USB mini or micro; I gotta get a cable. Mine has the comparator IC marked only, "AJK BAA." Yes, this is an Analog Devices
By Larry McDavid · #86138 ·
Re: Frequency calibration?
What's wrong with my Rubidium reference that would make me choose a GPS disciplined? Costed me $75 on EPay, but still needs a power supply, case and diastribution amplifiers, yet another project to
By Ovidiu Popa [Business] · #86137 ·
Re: Frequency calibration?
I have the same equipment and don't need insane accuracy (1Hz in 100MHz is more the sufficient - 10e-8). I will put the 1PPS signal into the A input, the 10MHz from the ref osc out on the back into
By WA2SCL_Jeff · #86136 ·
Re: Frequency calibration?
They say coffee helps you live longer, I don’t know about how true that is but I do know that it definitely makes me enjoy the time I do have much more! Peter
By Peter Gottlieb · #86135 ·
Re: Frequency calibration?
?????? There are many of us who are slaves to coffee. Have few other bad habits but I can't even talk in the morning before drinking a cup. -- Richard Knoppow dickburk@... WB6KBL
By Richard Knoppow · #86134 ·
Re: Fast Rise/Fall Time Pulser
Yes, works as advertised as far as I can tell. There is plenty of discussion and many screenshots
By Orin Eman · #86133 ·
Re: Frequency calibration?
Two questions for the original poster: How accurate do you need (want) to be? and what are you using the counter for? Time and frequency precision can become an obsession - Time Nuttery. Robert
By Robert G8RPI · #86132 ·
Fast Rise/Fall Time Pulser
There has been discussion recently about generating fast rise/fall time pulses by various means. Here is a link to a Leo Bodnar device that will provide <40 ps rise/fall time, 50% duty cycle, 10 MHz
By Larry McDavid · #86131 ·
Re: Frequency calibration?
Correct! Need more caffeinated beverage. Thanks! [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
By bownes · #86130 ·
Re: Frequency calibration?
?????? On a standard scope with the same signal on X and Y in phase is a line at 45degrees to the right, 180degrees out of phase is a straight line tilted 45 degrees to the left, a circle is 90
By Richard Knoppow · #86128 ·
Re: VNA design engineer on the list?
Dr. Joel Dunsmore hangs out in the Forums on HP/Agilent/Keysight. [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
By bownes · #86129 ·
VNA design engineer on the list?
If anyone here designed commercial VNAs, I'd like to call attention to some recent posts I've made to the EEVblog metrology forum on the topic of using an SA and a computer to measure amplitude and
By Reginald Beardsley · #86127 ·
Re: Frequency calibration?
By far and away the best choice is going to be a GPS disciplined oscillator such as an HP 3801A or a Thunderbolt. A good GPSDO should be good to at least 1x10^-10 ? (1ppb) over the course of a day.
By bownes · #86126 ·
Re: Schematics for HP 8558B SA
As Dave from Artek says, it is helpful to know the serial number of the unit. What you most likely want is the "Operation and Service Manual" for this unit. The part number for the manual is
By Ken Nener · #86125 ·
Re: Frequency calibration?
I can't recall where, but someone posted a comment to the effect that the PPS output of their GPS unit had significant (~20 nS) jitter. I'd suggest feeding the output of the reference to be checked
By Reginald Beardsley · #86124 ·
Re: Frequency calibration?
Ok. So you have a Trrimble Thunderbolt GPS?
By Anders · #86123 ·