¿ªÔÆÌåÓý

  1. HP-Agilent-Keysight-Equipment
  2. Messages
Messages Topics Expanded
Date
Re: HP 141T Power Supply Help Needed
To amplify your comment, many times older linear supplies, when they are brute force recapped, with the best, long life, low esr caps you can find, will become beacons of chaotic oscillation. I put a
By Chuck Harris · #146630 ·
Re: HP 141T Power Supply Help Needed
Thanks, Dave B. "To slug" = "to make sluggish". Thought so. Still, I still have never heard the term in 50-plus years of electronics work, including college courses in control system theory. The base
By Dave Wise · #146629 ·
Re: Schottky Diode degradation / Replacement in instrument Sram Battery backup circuits ?
Is this failure is related to having a few uA running through the metal junction for decades? Personally, if it took 30+ years to get so leaky, then I would still replace it with a new schottky - and
By Edward Prest · #146628 ·
Re: Instrument Sram ( non Dallas ) Battery replacement: Original 3.0V Li+ >> To 3.6V Li+ & Schottky Diodes ?
The question is about substituting? a long life, low leakage 3.6V Li+ Solder Tab, 10+ year battery ( Such as Tadiran or SAFT LSH-14 cell ) .... of at least 1200 mAh to 1600mAh capacity, instead of
By gren · #146627 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
Hi all Yeas its a very nice tool.Mine came with https://www.hpmemoryproject.org/an/pdf/an_183.pdf High Frequency Swept Measurements. Hardy Fra: [email protected]
By hardyhansendk · #146626 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
Very good! This what I was getting at.? I have a little slide rule from HP that does the 20 LOG(1+rho1*rho2)^2? for the mismatch. Nice calculation tool. Helps when relating VSWR effects to amplitude
By Jeff Kruth · #146625 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
If it helps to add some numbers to all this then consider the case up around 22GHz where the sig gen source VSWR might be 1.8:1 typical. This is poor enough to add significant mismatch uncertainty
By jmr · #146624 ·
Re: HP 141T Power Supply Help Needed
Hi. It's just a generic term (damping is another) to slow down the response of a loop, to prevent it going unstable. Not an uncommon issue in some linear PSU's like those -12.6V or -100V regulator
By Dave_G0WBX · #146623 ·
Re: 8566B Can't Calibrate
I fully agree. Subbing a 10dB attn sounds like a plan to me. Unfortunately I don't have time this week, but perhaps next I'll give it a go. At any rate, it's clearly the first thing I should try.
By Jinxie · #146622 ·
Re: 8566B Calibration
Jack and Bruce - many thanks. It all helps to work out what's happening. I only posted a photo of what I saw with the default calibration where the SA is automatically set at 10dB. It's the exact same
By Jinxie · #146621 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
In my experience, and this is across many decades of using all kinds of lab sig gens, the signal generators that use a classic levelling loop do not give an infinitely low generator VSWR up at high RF
By jmr · #146620 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
Some of the responses did not answer the question you asked. To answer the question below: modern signal generators, like the 8340, have a leveling loop to maintain a preset level. If you investigate
By Jeff Kruth · #146619 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
If it helps, this is the setup I typically use to level a microwave signal source and provide a low source VSWR. This provides levelling to the accuracy of the power meter and the source impedance is
By jmr · #146618 ·
Re: 8566B Can't Calibrate
Never mind my previous question - the picture you sent confirms the problem is most likely the attenuator.? I like the idea of subing a 10dB fixed for the switched attenuator followed by RECALL 8 and
By Bruce · #146617 ·
Re: 8566B Calibration
One more question and then I'll "buzz off" and watch.? Did you see anything when you did RECALL 8. I read that you did not see anything when you did RECALL 9 If RECALL 8 worked and RECALL 9 did
By Bruce · #146616 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
These have a DC output, not RF so input impedance of the test equipment doesn't matter. They typically feed the vertical a scope or DC voltmeter . [email protected]> wrote:
By Michael A. Terrell · #146615 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
The input VSWR of the 8473C is quite good up to about 18GHz, but above this a decent attenuator will have a lower VSWR.? So the attenuator acts to isolate the less than perfect VSWR of the sig gen
By jmr · #146614 ·
Re: Crystal detector with 10dB attenuator in series - is it for matching purposes?
Crystal detectors are often used after a tuned circuit that drives a 50 ohm load. Without the pad, you can't [properly align the circuit by itself. [email protected]> wrote:
By Michael A. Terrell · #146613 ·
Re: 8566B Calibration
I had exactly the same problem. Bought a replacement attenuator on ebay and installed it ..Fairly simple procedure.? Now I have a very happy 8566B.
By Jack · #146612 ·
Re: HP 141T Power Supply Help Needed
Bill, I suggest removing the fuse F4 and measure the resistance to ground at the terminals where the white / violet wires come to the board. With the fuse out the resistance to ground should be very
By Michael Bafaro · #146611 ·
5301 - 5320 of 151461