Ken
probably your best option would be a GPIB - PCI interface card for your PC or LAN/USB adapter - and National Instruments LabView
NI LabVIEW - Improving the Productivity of Engineers and Scientists
This will provide for both programming your Instruments, recovering and manipulating the data they measure. Expensive though!
There is also a LAN or USB to GPIB adapter from:
GPIB-LAN Converter - Control Oscilloscopes, Logic Analyzers, Spectrum Analyzers and other test Instruments via Ethenet
have a look at their Software links at the bottom of the page for saving and displaying results
Am beginning to use an NI interface Card here with Software from:
Linux GPIB Package Homepage
big learning curve!
Some software supports RS232 and/or USB instead of GPIB; but this seems to restrict comms to only one instrument where GPIB (HP-IB is the name for the same for HP instruments) you can have up to 15 connected at one time......
hope this assists
Mik
probably your best option would be a GPIB - PCI interface card for your PC or LAN/USB adapter - and National Instruments LabView
NI LabVIEW - Improving the Productivity of Engineers and Scientists
This will provide for both programming your Instruments, recovering and manipulating the data they measure. Expensive though!
There is also a LAN or USB to GPIB adapter from:
GPIB-LAN Converter - Control Oscilloscopes, Logic Analyzers, Spectrum Analyzers and other test Instruments via Ethenet
have a look at their Software links at the bottom of the page for saving and displaying results
Am beginning to use an NI interface Card here with Software from:
Linux GPIB Package Homepage
big learning curve!
Some software supports RS232 and/or USB instead of GPIB; but this seems to restrict comms to only one instrument where GPIB (HP-IB is the name for the same for HP instruments) you can have up to 15 connected at one time......
hope this assists
Mik
A cluttered bench signifies a cluttered mind. What does an empty bench signify....................? 🙂
The GM70 PP amp is a work in progress for some months now. its well hidden somewhere in the picture.
The GM70 PP amp is a work in progress for some months now. its well hidden somewhere in the picture.
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I recognize those Tek scopes, especially the 465 or 475's. I troubleshot and calibrated those back in the late 70's at Tektronix here in the Portland Oregon area. It's interesting that you are analyzing power factor on those speaker drivers. I've never heard of anyone doing that. In effect it's a measure of reactance if I understand what you're doing properly. High feedback poweramps are sensitive to that, especially at supersonic frequencies, where their feedback rolls off and introduces phase shift, thereby shrinking up the phase margin and setting up conditions for spurious oscillations, especially if the load is significantly reactive. I've found that no neg feedback anywhere works very good in guitar amps. I think the sound of the distortion, should you want it, is significantly better than with the high feedback circuits. This is of coarse very subjective.
A good friend of mine (Matt Kamna) here in Portland Oregon designed and built two 50 watt GM70 single ended poweramps. He bought about 100 GM70's from some guy in Russia, about 2/3 of them tested good, and they appear to be one of the better tubes out there, except that you need to have B+ of over 1kV. I guess there's not a lot of power trannys and filter caps to choose from up at that voltage. I think he said that the filiment dissipated 60 watts. It's like turning on a small lamp. They do sound great to my ear. I love your quote: "A cluttered bench signifies a cluttered mind. What does an empty bench signify.....?"
Yes, it is a very hungry tube. I have bought 26 tubes from someone in Ukraine so I have a private stash for my experiments.
The first one I build is vertical Nagra style and is working alright for two years now. This one is an experiment with a interstage transformer.
The first one I build is vertical Nagra style and is working alright for two years now. This one is an experiment with a interstage transformer.
Thanks Mik. I also found Pete Millett's info on this: HP 8903 Software so, I just picked up an HP GPIB - PCI card on ebay and will see what happens. Maybe with the plot interface listed on one of the sites you referenced.
Ken
A new test bench of course. The tradition around here used to be all benches clean on Friday or it gets thrown out. The prank came to be to leave a few charged capacitors out on Friday!
Always nice to look at other peoples stuff and then try to sort out all the shiny boxes🙂.
Just found the Anatech pictures.
Great to see a stereocoder from Radiometer Copenhagen on one of the pictures, or am I mistaken?
Just found the Anatech pictures.
Great to see a stereocoder from Radiometer Copenhagen on one of the pictures, or am I mistaken?
Humdinger
yup, the 465's and 468's I have are certainly good for Audio and the 7000 series mainframes for more specialized measurements....
Some early results on effects of reactive loads for some different Power Amplifiers here:
Amplifier Damping Factor - Dynamic Testing - Speakerplans.com Forums - Page 1
includes some results on detectable changes in distortion and other effects
and a follow up looking more at Amplifier dissipation with adverse Power Factors here:
Power Factors for 'Speakers - Speakerplans.com Forums - Page 1
When I get to having some more and better collated results then I'll post them on here as well; but for now these parameters are something I came across many years ago whilst designing High Power Amplifiers and only really have the time now I'm retired to properly investigate.....
Mik
They used to do inspections for proprietory material on Frifay afternoons. Everything we work on runs on 15 volts or less, so charged caps weren't much of a threat. I did find out that you can charge up a copy machine transparency sheet with an ESD gun and it will bite you good. The transparency must be placed on a conductive surface. If you are really evil sandwitch an old ESD bag (the kind with a conductive metal coating inside) between two transparencies placed on a conductive surface. After about 3 weeks the inspector simply bypassed my cube.
Hi George,
Please let me know what you think of the new U8903A once you've had time to play. The price seems to be very good (I'm out of money, so not for me) and the features excellent. I have not seen one in the flesh as yet. So they only use them for SINAD? Do you think they'll do a trade for something that only does SINAD? After all, too many functions can confuse people to no end.
As for benches, I had the cleanest bench in the cal lab when I was working there. It was cleaned twice a day, or if needed after working on filthy instruments. The Friday afternoon clean (is that common for every lab?) didn't cause me any concern, so I wandered around cleaning other assets and shelves.
Hi Mik,
Nice setup there! You can almost never have too many meters on a bench - well, maybe you can! 🙂
Hey Ken,
Agilent has free software for download on their site. I use GPIB for the older stuff. If I ever get anything new, LXI (ethernet) for sure. Tried it, love it.
Also on the Agilent site are all the manuals for the gear, and the software. My card is made by Conexant (?) and works well using the NI driver. You will find some software drivers and help screens with the 8903A information. Then download Intuitlink (I think) and another (IO Suite?). My bench 'puter is down right now, so I can't easily look at what I have running right now. Needless to say, not a problem.
Hi sycorax,
Does anyone have a manual for this thing? I've been flying blind for years now.
Many of you have an amazing collection of test equipment. You should all know that what many of you are using is well beyond what the average audio service shop has. That means you people are not fooling around. You all have the capability to do some amazing work.
-Chris
Please let me know what you think of the new U8903A once you've had time to play. The price seems to be very good (I'm out of money, so not for me) and the features excellent. I have not seen one in the flesh as yet. So they only use them for SINAD? Do you think they'll do a trade for something that only does SINAD? After all, too many functions can confuse people to no end.
As for benches, I had the cleanest bench in the cal lab when I was working there. It was cleaned twice a day, or if needed after working on filthy instruments. The Friday afternoon clean (is that common for every lab?) didn't cause me any concern, so I wandered around cleaning other assets and shelves.
Hi Mik,
Nice setup there! You can almost never have too many meters on a bench - well, maybe you can! 🙂
Hey Ken,
Agilent has free software for download on their site. I use GPIB for the older stuff. If I ever get anything new, LXI (ethernet) for sure. Tried it, love it.
Also on the Agilent site are all the manuals for the gear, and the software. My card is made by Conexant (?) and works well using the NI driver. You will find some software drivers and help screens with the 8903A information. Then download Intuitlink (I think) and another (IO Suite?). My bench 'puter is down right now, so I can't easily look at what I have running right now. Needless to say, not a problem.
Hi sycorax,
It's a Radiometer Copenhagen SMG1 FM Stereo generator. I've had it for years and rebuilt the power supply so far. The rest seems to be solid, and the distortion is pretty low too. I'm sure there are other better generators out there, but this is what I have. The MPX output can be fed into my HP generators to modulate the output in stereo, so that solves the problem of being stuck close to 100 MHz. I found a hole at 101.1 MHz in my neck of the woods that the SMG1 just reaches. The HP generators are far more stable and don't drift like the SMG1 does. Really excellent unit, especially when you consider when the SMG1 was in production.
Does anyone have a manual for this thing? I've been flying blind for years now.
Many of you have an amazing collection of test equipment. You should all know that what many of you are using is well beyond what the average audio service shop has. That means you people are not fooling around. You all have the capability to do some amazing work.
-Chris
I worked in the cal lab at Motorola for 10 years 1974 to 1984. Mostly doing factory floor support, hot swap outs of NFG (Non Functional Gear). My bench was always messy, that way the boss can't tell what I am doing. It's still a mess today. The phone camera picture cuts off the mess on the desk.
I spent the day walking the swap meet at the Dayton Hamfest, mostly buying tubes, but a 5KW RF amp followed me out to the car. OK I carried the damn thing.
There has been a vendor selling test equipment by the pound every year. This year the $1 per pound bin was full of the TEK 7000 series scopes like the ones in the picture on post #219. I have camera phone pictures but no easy way to get them out of the phone untill I get home (Monday).
The primary sensitivity measurement for the high tier two way radios we make is the RF level needed to make 12 db of SINAD. For the last 25 years the measurements were made on an 8903A or 8903B. Since these are no longer made we have switched to the U8903A. They do get used for distortion or AC level every once in a while.
I spent the day walking the swap meet at the Dayton Hamfest, mostly buying tubes, but a 5KW RF amp followed me out to the car. OK I carried the damn thing.
There has been a vendor selling test equipment by the pound every year. This year the $1 per pound bin was full of the TEK 7000 series scopes like the ones in the picture on post #219. I have camera phone pictures but no easy way to get them out of the phone untill I get home (Monday).
The primary sensitivity measurement for the high tier two way radios we make is the RF level needed to make 12 db of SINAD. For the last 25 years the measurements were made on an 8903A or 8903B. Since these are no longer made we have switched to the U8903A. They do get used for distortion or AC level every once in a while.
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Hi George,
Drool ...
What a lovely collection you have there!
I've always wanted to check that swap meet out. It's a stretch for me, but I really want to get down there some day. The tubes, the gear and I imagine the manuals.
-Chris
Drool ...
What a lovely collection you have there!
I've always wanted to check that swap meet out. It's a stretch for me, but I really want to get down there some day. The tubes, the gear and I imagine the manuals.
-Chris
So, A thread that started in 2006 and just came back to life. 🙄 I read the whole thing about a year ago, and forgot how to find it,😱 So glad its back. 😛
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That's my bench at work, My home workbench has a lot of good stuff, but not 1/2 a million dollars worth.
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I will have driven over 3000 miles by the time I get home.
You should spend more time on EBay -- it's entirely too neat!
Here's about 2/3rd of 'stuff' in my shops. I come from a long line of users of tools. Retired from Beech Aircraft in 2007 . . . my basement shop was the last of the 'skunk werks' facilities available to Beech . . . and now there are none.
Have acquired a good array of RF/AF/digital/analog electronics test equipment and materials in 40+ years as a professional. The recent addition of a well fitted woodworking shop adds a new dimension for cabinets and fixtures.
Have acquired a good array of RF/AF/digital/analog electronics test equipment and materials in 40+ years as a professional. The recent addition of a well fitted woodworking shop adds a new dimension for cabinets and fixtures.
Woodworking is more dangerous than electronics, but smells better.
My son flies a Hawker 800.