Re: Semiconductor test set advice
Quite complete info on the Tek 575/175 is here:
including 1963 catalogue pages, the Op/Serv manuals and the 'Some Transistor Measurements Using the Type 575' app note I'm about halfway thru re-doing. There were two versions: one with 0 to 20/200V Peak Voltage Range and the mod 122C with 0 to 20/200/400V capability.
You might also want to dig up the three recent and quite good iterations of vacuum tube testers as they interface with a PC. They are the uTracer:
the eTracer:
and the much more ambitious, capable, costly and, I'm told, difficult to build RoeTest:
Best, Bill Perkins
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Re: Semiconductor test set advice
On 4/27/20 12:38 PM, David C. Partridge wrote: The lead developer was unbelievable; his stated position was that any API (yes, API!) that hasn't changed in the past few weeks "isn't being updated" and is therefore "dead". Believe it or not, it actually went downhill from there. OMG who hired that idiot!
He sold himself to the company's (largely nontechnical) management as a "cool" modern developer who could develop "cool" and "fresh" web interfaces. He went on to go from employee to contractor, then started his own consulting firm, still doing the same job for that same company, and bilked the company for large amounts of money. Beware the word "fresh" coming from "tweenager" software developers. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Semiconductor test set advice
...and we wonder these days why people have the attention span of a hyperactive gnat.? It aggravates me when they constantly make little changes to interfaces so that things that were there are either no longer there, or move a bit, or work differently.? It feels like gaslighting - I swear I did this last week, why does it not seem to work now?!? Design it then leave it the eff alone!!? There's something to be said for panels with knobs and switches on them - people are less inclined to rearrange them for? ?...reasons... -Pat
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On April 27, 2020 at 11:58 AM Dave McGuire <mcguire@...> wrote:
On 4/27/20 10:02 AM, Reginald Beardsley via groups.io wrote:Occulus, Thanks. Yahoo changed the interface so that it doesn't show unread messages in the SPAM bin :-(
As a consequence I've been forgetting to check and empty it as I used to do every day.
I do wish that "developers" would realize that people do *not* want the UI to change constantly. Actaully I think it's what a lot of the kids DO want. If it looks the same as it did yesterday, it's not "FRESH!"
I worked with some developers a few years ago that were of that mindset. They were doing the web app and back end that talked to firmware I was writing. The lead developer was unbelievable; his stated position was that any API (yes, API!) that hasn't changed in the past few weeks "isn't being updated" and is therefore "dead". Believe it or not, it actually went downhill from there.
-Dave
-- Dave McGuire, AK4HZ New Kensington, PA
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Re: Semiconductor test set advice
The team lead on the C++ project I alluded to in another thread was like that. I found delicious irony in the outcome of the story. When ARCO got bought, BP was not allowed to keep ARCO's North Slope assets. As a consequence ConocoPhillips bought them and got the system I'd worked on. I learned from friends that they kept all my code in C & FORTRAN and pitched the C++.
The part that really blew my mind was there was a 6x differential in productivity. It took them 6 weeks to build the UI for 1 week of my work. I saw why when I was asked to fix a piece of the UI code as I'd run out of things to do and they were behind. It was a single, several thousand line function created by a UI builder and then hacked. I fixed it, but was so disgusted I told the project manager I would not work on any more of it. I signed my name to my code and included my ACM email address in the header comment. I got laid off not long after and ARCO was sold to BP a few months later.
The saddest part of that project was sitting with another scientist while he was testing it. If you wanted to display 6 curves, it drew one, erased the screen, drew two, erased the screen and so forth until all of the traces had been drawn. This took about a minute and he would just giggle. And if you attempted to scroll up or down in the curves it repeated all the redraws. The team lead tried to get me to join LinkedIn so he could reference me. I declined.
My first contract project was in active use for 12-14 years with about 1/2 that unmaintained. We had 12 user bugs the first year and it went to near zero. There were a pair of 15,000 line libraries in that package that *never* had a bug found. The single change was when Sun broke the C stdlib and failed to correctly set errno on a call to getcwd(3c). The fix was to test for a null pointer return on Sun systems. It also ran from the same source on AIX, HP-UX, IRIX, Ultrix, CLIX (Intergraph) in addition to SunOS/Solaris. Except for things like the Sun gaff the only #ifdefs were byte sex and FORTRAN RECL= bytes or words. It was a 500,000 line port from VAX FORTRAN & VMS to Unix. Lots of it written by scientists who were not good programmers.
The coolest part of that project was the build system, YAMS, Yet Another Make System. You could create a directory, cd to it, and check out the source code. You could then open xterms on all the systems in that same directory and after making a change, could simultaneously compile and run the regression test suite on all platforms. This made everyone very sensitive to the language standards and portability. The IRIX and Ultrix ports were done as an afternoon lark by me when I didn't really have anything serious to do. Probably waiting for a staff meeting.
Good programmers never have to modify their code unless someone else breaks theirs.
Have Fun! Reg
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Re: Semiconductor test set advice
The lead developer was unbelievable; his stated position was that any API (yes, API!) that hasn't changed in the past few weeks "isn't being updated" and is therefore "dead". Believe it or not, it actually went downhill from there. OMG who hired that idiot! David
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Re: Semiconductor test set advice
Sean, the option for the Tek 575 that's eluding you is Mod 122C - it adds a third range of 0-400V @ 0.5A to the 0-20V @ 10A and 0-200V @ 1A collector sweep supply of the standard instrument. -Pat
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On April 27, 2020 at 11:52 AM [email protected] wrote: Yeah, complete UI/UX changes with web services seem to be par for the course these days. Farcebook is a leading example. But I digress... Another thing to keep in mind with the Tek curve tracers is some of them develop HV transformer difficulties (lots of info about this+repair strategies on TekScopes); however, they are indispensable if you need to characterize high power parts. The 575 with a particular special option (name and number escapes me) is even better for this. I'd personally like to find a good one with that option as it would be a great curve tracer and would satisfy the itch to have one glowing Tek with vacuum tubes and ceramic strip construction. :o) It doesn't have blanking though, so things like families of curves will show retrace unlike a 577 or 576. The 577 also has the advantage of basically being made of standard 5000 series oscilloscope parts, unlike the 576 which is large and more complicated with the fiber optics to light the display annunciators. You can also get the 577 with a storage crt, but whether that crt will have any life left is questionable most likely. As I understand it, the semiconductor parameter analyzer that HP marketed was really more intended to be an analytical lab instrument mainly focused on characterizing lower-power parts, while Tek curve tracers often were used on production lines for matching components and stuff like that. This at least partially explains why a lot of 577 and 576 curve tracers that come up for sale are beat up pretty badly. And as you observed, good condition examples command high prices. I understand where you are coming from wanting to be able to do whatever measurement you need. I'm working to build up to that and also be able to calibrate my own stuff. Perhaps we can have a discussion offline about what you've found indispensable, as I believe our interests align quite a bit in the microwave realm. Cheers! Sean On Mon, Apr 27, 2020 at 07:02 AM, Reginald Beardsley wrote:
Occulus, Thanks. Yahoo changed the interface so that it doesn't show unread messages in the SPAM bin :-( As a consequence I've been forgetting to check and empty it as I used to do every day. I do wish that "developers" would realize that people do *not* want the UI to change constantly. Keysight didn't have much on their stuff on the website, but I eventually found copies of the manuals at some of the repair shops. It appears that a 4145B is what I want (i.e. is cheap enough I can afford it ). Perhaps augmented by a Tek 576 or 577, but those look rather expensive and hard to find. In general I want to be able to make pretty much any test I might need. At the time I was most active designing and building stuff all I had was a 5 MHz recurrent sweep single channel scope (banana plug input), a VOM and a DMM. All my other test gear was DIY. Trying to build radios from scratch with that is pretty much a lost cause. But I was in my early 30's on my 2nd pass through grad school. So I had no budget for things other than books. Those were very expensive, though now it appears to be worse. Reg
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Re: Semiconductor test set advice
On 4/27/20 10:02 AM, Reginald Beardsley via groups.io wrote: Occulus, Thanks. Yahoo changed the interface so that it doesn't show unread messages in the SPAM bin :-(
As a consequence I've been forgetting to check and empty it as I used to do every day.
I do wish that "developers" would realize that people do *not* want the UI to change constantly. Actaully I think it's what a lot of the kids DO want. If it looks the same as it did yesterday, it's not "FRESH!" I worked with some developers a few years ago that were of that mindset. They were doing the web app and back end that talked to firmware I was writing. The lead developer was unbelievable; his stated position was that any API (yes, API!) that hasn't changed in the past few weeks "isn't being updated" and is therefore "dead". Believe it or not, it actually went downhill from there. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Semiconductor test set advice
Yeah, complete UI/UX changes with web services seem to be par for the course these days. Farcebook is a leading example. But I digress...
Another thing to keep in mind with the Tek curve tracers is some of them develop HV transformer difficulties (lots of info about this+repair strategies on TekScopes); however, they are indispensable if you need to characterize high power parts. The 575 with a particular special option (name and number escapes me) is even better for this. I'd personally like to find a good one with that option as it would be a great curve tracer and would satisfy the itch to have one glowing Tek with vacuum tubes and ceramic strip construction. :o) It doesn't have blanking though, so things like families of curves will show retrace unlike a 577 or 576. The 577 also has the advantage of basically being made of standard 5000 series oscilloscope parts, unlike the 576 which is large and more complicated with the fiber optics to light the display annunciators. You can also get the 577 with a storage crt, but whether that crt will have any life left is questionable most likely.
As I understand it, the semiconductor parameter analyzer that HP marketed was really more intended to be an analytical lab instrument mainly focused on characterizing lower-power parts, while Tek curve tracers often were used on production lines for matching components and stuff like that. This at least partially explains why a lot of 577 and 576 curve tracers that come up for sale are beat up pretty badly. And as you observed, good condition examples command high prices.
I understand where you are coming from wanting to be able to do whatever measurement you need. I'm working to build up to that and also be able to calibrate my own stuff. Perhaps we can have a discussion offline about what you've found indispensable, as I believe our interests align quite a bit in the microwave realm.
Cheers!
Sean
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On Mon, Apr 27, 2020 at 07:02 AM, Reginald Beardsley wrote:
Occulus, Thanks. Yahoo changed the interface so that it doesn't show unread messages in the SPAM bin :-(
As a consequence I've been forgetting to check and empty it as I used to do every day.
I do wish that "developers" would realize that people do *not* want the UI to change constantly.
Keysight didn't have much on their stuff on the website, but I eventually found copies of the manuals at some of the repair shops. It appears that a 4145B is what I want (i.e. is cheap enough I can afford it ). Perhaps augmented by a Tek 576 or 577, but those look rather expensive and hard to find.
In general I want to be able to make pretty much any test I might need. At the time I was most active designing and building stuff all I had was a 5 MHz recurrent sweep single channel scope (banana plug input), a VOM and a DMM. All my other test gear was DIY. Trying to build radios from scratch with that is pretty much a lost cause. But I was in my early 30's on my 2nd pass through grad school. So I had no budget for things other than books. Those were very expensive, though now it appears to be worse.
Reg
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Anyone from HP that worked on the design of the 1700 Series Scopes?
I am trying to find details on parts used in the design of the 1703A and the 1707B. Specifically the FET's used in Option 20 the Vertical Output Amplifier. These would be matched FET's HP Part number 1855-0085.
These parts are not found in the cross reference so it would be good to know what the base part number is and it someone might know what the matching parameters are.
I would like to clone this board (an perhaps make a wider bandwidth one) so having additional info on it would be great.
I have the schematics for both of the designs that were used the one from the 1707B OPT 300 military scope and one from the 1703A. The 1707B one used a 2N4044 matched NPN? in a TO-78 can followed by a pair of 2N3906's. The 1703A one uses a matched pair of N-Channel JFETS followed by a PNP/NPN for output drive with a 741 op-amp. It's a clever design for the time using the op-amp for the DC path and using AC coupling for the high frequency (such as it was then) path.
In any event finding the original parts in any quantity would be a problem so a re-design that uses modern parts would be better. I have already completed a PCB layout for the 1707B version using the original parts which got me thinking that others may want one as well so that led me to be thinking about something using modern op-amps, etc.
So I am hoping that some there are some members of the group that worked on these scopes.
Thank you,
Sam W3OHM
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Re: How to check the accuracy of an HP 5342A frequency counter
FWIW General Radio in the instructions for one of its early frequency measuring assemblies recommended the "three oscillator" method of measuring differences. Where a source is being compared to WWV the third oscillator can be the BFO in the receiver. The BFO is set for an audio beat and the waxing and waning of the beat from the other two can be heard plainly. It is possible where the signals are steady to detect and measure fractional cycle beats this way. Since your standard runs on a WWV frequency it should be trivial to determine if its on frequency. Since you have three measuring instruments all showing the same approximate error I rather think the standard is off. If its adjustable you can likely get it closer using this method. ?? My understanding from long ago is that a rubidium oscillator is used mainly as a filter to eliminate phase noise from a cesium clock.
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On 4/27/2020 8:22 AM, Edward Newman via groups.io wrote: First, make sure the Rb standard is locked. Second, couple the output of the Rb to a receiver and check it against WWV. ?Adjust the coupling so that the Rb signal is about the same strength as WWV. You should be able to detect errors of a few Hz pretty easily. Even without a recent cal the Rb standard, if locked, should be better than 1Hz at 10 MHz. ?If the standard checks out you can then adjust the ref oscillator in each counter to read exactly 10 MHz on the counter. However, I'm betting there is a problem with the standard, since all the counters show the same error. Remember all these Rb standards were pulled because they were pretty worn out. I had one stop locking, and now have two, checked against a GPSDO. ?I can set mine to about .001 Hz against the GPSDO. Finally, after using the Rb for a while I realized that none of the internal ref oscillators are as stable as the Rb, so I just feed the counter the Rb as a reference. Since I got my Rb reference GPSDO have gotten a lot less expensive, so if your Rb is misbehaving I'd suggest buying one of those.
Ed. W2EMN
On Apr 26, 2020, at 10:34 PM, Terry Maurice <ve3xtm@... <mailto:ve3xtm@...>> wrote:
I have two of these units, one has the oven the other does not.? The two units do not read exactly the same value when fed with a signal from a 10MHz FE-5680A, rubidium frequency standard.? I am monitoring the frequency standard with the two HP units and my Siglent SSA 3021X spectrum analyzer, all units being fed from the rubidium standard through a Downeast Microwave 10-4, 10MHz amplifier and filtered 4-way divider. The units have been on for about 5 hours before taking the readings below.
Unit A (with crystal oven) reads 9,999,828 Hz, +/- 2 Hz; unit B reads 9,999,830 Hz, +/-2 Hz and my spectrum analyzer reads 9,999,826 Hz.? Are these values within the expected values for these older frequency counters?? Is the FE-5680A correct? I checked both HP 5342As with their internal references and both show 10MHz.? How can I know, which unit(s) are correct, or do I assume my rubidium frequency standard is off by about 170 Hz?
The FE-5680A does generate some heat when left on for prolonged periods, however, It is mounted on an aluminum heatsink and sealed inside a solid metal box, but the metal case is only slightly warm to the touch.? On my oscilloscope, the output of the rubidium standard shows a distorted wave, but once it passes through the DEM 10-4 it is a clean sine curve.
Any help or comments would be much appreciated.
Terry
-- Richard Knoppow dickburk@... WB6KBL
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Re: How to check the accuracy of an HP 5342A frequency counter
First, make sure the Rb standard is locked. Second, couple the output of the Rb to a receiver and check it against WWV. ?Adjust the coupling so that the Rb signal is about the same strength as WWV. You should be able to detect errors of a few Hz pretty easily. Even without a recent cal the Rb standard, if locked, should be better than 1Hz at 10 MHz. ?If the standard checks out you can then adjust the ref oscillator in each counter to read exactly 10 MHz on the counter.? However, I'm betting there is a problem with the standard, since all the counters show the same error.? Remember all these Rb standards were pulled because they were pretty worn out. I had one stop locking, and now have two, checked against a GPSDO. ?I can set mine to about .001 Hz against the GPSDO. ? Finally, after using the Rb for a while I realized that none of the internal ref oscillators are as stable as the Rb, so I just feed the counter the Rb as a reference. Since I got my Rb reference GPSDO have gotten a lot less expensive, so if your Rb is misbehaving I'd suggest buying one of those.?
Ed. W2EMN
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On Apr 26, 2020, at 10:34 PM, Terry Maurice < ve3xtm@...> wrote: I have two of these units, one has the oven the other does not.? The two units do not read exactly the same value when fed with a signal from a 10MHz FE-5680A, rubidium frequency standard.? I am monitoring the frequency standard with the two HP units and my Siglent SSA 3021X spectrum analyzer, all units being fed from the rubidium standard through a Downeast Microwave 10-4, 10MHz amplifier and filtered 4-way divider.? The units have been on for about 5 hours before taking the readings below.?
Unit A (with crystal oven) reads 9,999,828 Hz, +/- 2 Hz; unit B reads 9,999,830 Hz, +/-2 Hz and my spectrum analyzer reads 9,999,826 Hz.? Are these values within the expected values for these older frequency counters?? Is the FE-5680A correct? I checked both HP 5342As with their internal references and both show 10MHz.? How can I know, which unit(s) are correct, or do I assume my rubidium frequency standard is off by about 170 Hz?
The FE-5680A does generate some heat when left on for prolonged periods, however, It is mounted on an aluminum heatsink and sealed inside a solid metal box, but the metal case is only slightly warm to the touch.? On my oscilloscope, the output of the rubidium standard shows a distorted wave, but once it passes through the DEM 10-4 it is a clean sine curve. ?
Any help or comments would be much appreciated.
Terry?
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Wanted: HP 8445b Preselector
hi,
Wanted: HP 8445b Preselector .
Please contact me off-list.
thank you, rick
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Re: How to check the accuracy of an HP 5342A frequency counter
Thanks Chuck for that information.? I suspect that my rubidium reference may be on the old side.? I bought it used over 8 years ago and I used it a fair amount as a frequency reference for my Flex 5000A, when I had that rig operational.
The locked light does come on after a few minutes of operation.
And thanks to all for the comments and suggestions.? I will work through them and see what I find.
Terry
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On 2020-04-27 7:47 a.m., Chuck Harris wrote: Atomic references are in general, short lived. Cs beam's run out of vacuum, or out of Cs (some debate about that!). Rb references plate out the Rb metal on the lamp's glass bulb, and get to a point where not enough light can get past the plated out Rb metal film for the detector to operate.
The Rb can very often be fixed when the lamp goes dark by using a heat gun to evaporate the Rb on the inside of the bulb where the light is emitted, and let it plate out somewhere else.
The biggest problem is gaining access to the Rb bulb. Many of the compact units are essentially assemble only devices.
When either a Cs beam standard, or a Rb reference runs out of "physics" to operate, its disciplined VCXO will end up against its rails too high, or too low in frequency (depending on how it was designed).
Also, crystal ovens are a reliability problem. They are electrically heated devices, and as such must be protected against thermal runaway situations... lest they catch fire.
[I have seen oven failures where the entire oscillator board melted its solder, and parts dropped out.]
In many cases, the thermal fuses installed inside of the oven will fail, even though there is nothing otherwise wrong with the oven. But again, they are usually assemble only devices, and replacing the fuse will require serious removal efforts.
-Chuck Harris
Dr. Frank wrote:
I fully agree to Ed Breya. Your Rb standard very probably is not locked, 17ppm off is a typical sign for that. All such OCXOs (10544 or 10811) can never be out that far, if they are operating correctly (i.e. getting warm, please check). As both OCXO agree to each other, they seem to be working. Please check the LOCK signal of your Rb clock.
After you identified the root cause, further hints how to correctly adjusti either of your clocks can be given.
Frank
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Re: Semiconductor test set advice
Occulus, Thanks. Yahoo changed the interface so that it doesn't show unread messages in the SPAM bin :-(
As a consequence I've been forgetting to check and empty it as I used to do every day.
I do wish that "developers" would realize that people do *not* want the UI to change constantly.
Keysight didn't have much on their stuff on the website, but I eventually found copies of the manuals at some of the repair shops. It appears that a 4145B is what I want (i.e. is cheap enough I can afford it ). Perhaps augmented by a Tek 576 or 577, but those look rather expensive and hard to find.
In general I want to be able to make pretty much any test I might need. At the time I was most active designing and building stuff all I had was a 5 MHz recurrent sweep single channel scope (banana plug input), a VOM and a DMM. All my other test gear was DIY. Trying to build radios from scratch with that is pretty much a lost cause. But I was in my early 30's on my 2nd pass through grad school. So I had no budget for things other than books. Those were very expensive, though now it appears to be worse.
Reg
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Re: How to check the accuracy of an HP 5342A frequency counter
Atomic references are in general, short lived. Cs beam's run out of vacuum, or out of Cs (some debate about that!). Rb references plate out the Rb metal on the lamp's glass bulb, and get to a point where not enough light can get past the plated out Rb metal film for the detector to operate.
The Rb can very often be fixed when the lamp goes dark by using a heat gun to evaporate the Rb on the inside of the bulb where the light is emitted, and let it plate out somewhere else.
The biggest problem is gaining access to the Rb bulb. Many of the compact units are essentially assemble only devices.
When either a Cs beam standard, or a Rb reference runs out of "physics" to operate, its disciplined VCXO will end up against its rails too high, or too low in frequency (depending on how it was designed).
Also, crystal ovens are a reliability problem. They are electrically heated devices, and as such must be protected against thermal runaway situations... lest they catch fire.
[I have seen oven failures where the entire oscillator board melted its solder, and parts dropped out.]
In many cases, the thermal fuses installed inside of the oven will fail, even though there is nothing otherwise wrong with the oven. But again, they are usually assemble only devices, and replacing the fuse will require serious removal efforts.
-Chuck Harris
Dr. Frank wrote:
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I fully agree to Ed Breya. Your Rb standard very probably is not locked, 17ppm off is a typical sign for that. All such OCXOs (10544 or 10811) can never be out that far, if they are operating correctly (i.e. getting warm, please check). As both OCXO agree to each other, they seem to be working. Please check the LOCK signal of your Rb clock.
After you identified the root cause, further hints how to correctly adjusti either of your clocks can be given.
Frank
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Re: How to check the accuracy of an HP 5342A frequency counter
I fully agree to Ed Breya. Your Rb standard very probably is not locked, 17ppm off is a typical sign for that. All such OCXOs (10544 or 10811) can never be out that far, if they are operating correctly (i.e. getting warm, please check). As both OCXO agree to each other, they seem to be working. Please check the LOCK signal of your Rb clock.
After you identified the root cause, further hints how to correctly adjusti either of your clocks can be given.
Frank
?
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Re: Maximum depth of HP rack mountable gear?
Avoid IKEA. Much of their furniture is hollow on the inside, especially the worktop desk surfaces. El Wife found that out painfully when drilling...
With best regards Tam HANNA
Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at
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On 2020. 04. 27. 3:21, Jim Ford wrote: Yeah, don't discount kitchen DIY furniture as found at places like IKEA. ?The wife and I redid our computer/music/scrapbooking room with kitchen cabinets rather than the office stuff about 7 years ago. IKEA had way better selection in the kitchen department than in the office department.? The office stuff they offered was really lame!? Of course now with the Corona Virus and working from home, my laptop computers and desk area get a lot more use!
Jim Ford
------ Original Message ------ From: "Tam Hanna" <tamhan@...> To: [email protected] Sent: 4/24/2020 10:55:02 PM Subject: Re: [HP-Agilent-Keysight-equipment] Maximum depth of HP rack mountable gear?
Wife introduced kitchen work surfaces (Kuechenarbeitsplatte). Cheap, can be had at home improvement store, works well here.
Tam
With best regards Tam HANNA
Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at
On 2020. 04. 25. 7:50, John Parkins G8KVP wrote:
Hello Dave,
No nothing bad at all, just making it more difficult for ourselves.
When we moved house I took over a room for my gear, so I was able to build benches, shelves etc as I wanted them. At first it was fine, but I think as we all do a flat surface is for putting things on. So the amount of available work area reduces and reduces until we're trying to work on a large bit of gear in a space which isn't quite big enough...... I've over come this by having a removable 'bench' which is only put into place when I need the extra room and removed afterwards. If it were left in place it would end up covered in stuff! We can't help it, I think it's in all our natures to collect.
Friday, April 24, 2020, 6:53:46 PM, you wrote:
DM> On 4/24/20 12:27 PM, John Parkins G8KVP wrote:
WORKBENCH! How ever wide you make them they just aren't wide enough. DM>?? Unfinished flat doors make very good workbenches. And desks, for that DM> matter.
Why do we do this to ourselves? DM>?? You say this as if there's something bad about it.
DM>???????? -Dave
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Re: RMS voltmeter HP 3400A - what does option C61 stand for?
Thanks, Jeremy,? Sean, Mine has C61 as well and it's no different from non-C61 version visually or in performance. Leo
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Re: How to check the accuracy of an HP 5342A frequency counter
The rubidium should be the most accurate of the bunch, except for the GPSDO. The method I have used is similar to the X-Y lissajous, but I use A, B ch, with B ch trig on a 100+MHz o-scope. Show both traces then adjust A freq source to stop the trace walking, decrease the sweep time down to the nsec. range, adjusting the A freq source for minimum trace walk. The faster sweep time gives you more resolution and allows you to adjust 10 MHz to within .001 Hz. Wait 10-30min. and recheck for A trace movement from the B triggered trace. I have achieved <1E-13 MHz separation from the 10 MHz reference source, using this method. Don Bitters
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Re: Semiconductor test set advice
Hello,
Tek 577 plus Stinkely Consumer Edition 577.
(around 1 grand, probably 400 bux or so)
Tek 577 plus Stinkely 577.
(around 1 grand, probably 1k2 bux or so)
Tam
With best regards Tam HANNA
Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at
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On 2020. 04. 27. 4:47, Dave McGuire wrote: On 4/26/20 10:02 PM, Reginald Beardsley via groups.io wrote:
I'd like to get a semiconductor test set. Preferably something that will send output to a printer. rather than have to photograph a screen. I've got a Peak Atlas DCA75, but I'd like something better. Building one is appealing, but time consuming.
McGuire commented on an HP unit he uses, but I can't find the post and my email to him apparently wound up in the spam bin. Uhh, check your own spam bin, Sparky. ;) I replied to that email, 4/24 12:05AM.
-Dave
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