It looks like I'm now the proud (?) owner of a Quan-Tech 5173 semiconductor noise analyzer. It looks like it will come with a fixture for checking opamps. I guess it'll be my burden to come up with a jig of some sort for checking 3-legged beasties. Does anyone have any documentation/advice for running one of these?
Well, the fixture that comes with the analyzer is configured for measuring quad op amps of some sort. I suspect that there's some sleight of hand going on inside the fixture that allows it to be used with the basic analyzer (there's switches and a knob, as well as a zif socket for the UUT). What I'll be mostly needing is information on how to use the analyzer and how to hook into the ribbon cable connectors on the back side of the analyzer, which I suppose would be the connection to whatever fixture is used with the main box. If I'm spouting doo-doo here and another major piece is needed, let me know. What I'm getting is the box with the displays, and a separate fixture built into a slope-front box.
I purchased a 5173 from an automotive electronics firm in Michigan back when the industry was its nadir. Here's a block diagram:
An externally hosted image should be here but it was not working when we last tested it.
I put the pin assignments up on this web-page: DIY Test Equipment for Audio and Ham Radio Enthusiasts
I have a QuanTech 5173 as well. The manual is really light on details on the interface modules. Mine has a bipolar plugin and I made an IC interface for it. There are a few tricks to making them. First, the edge connector is .1" spacing. I used a connector chopped from an old ISA computer board. The transistor fixture needs some ferrite beads or you can have oscillations. The IC side supports up to 4 sections, the transistor only a single transistor. Dual transistors require opening and flipping the dual around. The other pain is the cost of transistor test sockets. The good 3M sockets are $30 ea. or more. There are other types on eBay etc but they don't work well with TO92 packages. And test sockets for surface mount parts are even more of a problem.
The cable between the test fixture and the main box is a standard cable, mine came from a surplus store.
The cable between the test fixture and the main box is a standard cable, mine came from a surplus store.
The whole thing is special. The test box is separate so the noise from the main circuitry won't degrade it I think and has the low noise preamp and the AGC in it. The main box has the power supplies and filters and readouts.
If you get stumped getting it running we could meet since you aren't far away.
If you get stumped getting it running we could meet since you aren't far away.
Mr. Watt-Sucking Fireball at Linear Systems in Fremont has the same analyzer with the test box I'd actually like to have. Between the three of us, I think I can work something out. I haven't even gotten the blasted thing yet, so it'll be a while before I get busy on it, especially as my plate (as always) is piled high and overflowing...
I got the Quan-Tech box today. The interface module is definitely for Quad opamps, so I'll have to trick it out to handle 3-legged critters as well.
No cables came with the box. I suspect the interconnects might use shielded ribbon cable, but I'd like some confirmation if that is true... I need to know, as it looks I'll be stuck putting my own cables together.
No cables came with the box. I suspect the interconnects might use shielded ribbon cable, but I'd like some confirmation if that is true... I need to know, as it looks I'll be stuck putting my own cables together.
Mine came without a cable as well. A trip to Halted solved that issue. Shielding is not necessary since the signal level is quite high across the wire.
The module under the lid unplugs and that's where you plug in the transistor fixture. You may need several for different pinouts, or bend the pins which is what I do. My transistor fixture is rigged for N Jfets for now. The space is pretty small but it may be possible to kludge a pair of switches for different pinouts and two transistors in that space.
I have a really low noise Jfet that came from Quan-Tech for checking the calibration.
The module under the lid unplugs and that's where you plug in the transistor fixture. You may need several for different pinouts, or bend the pins which is what I do. My transistor fixture is rigged for N Jfets for now. The space is pretty small but it may be possible to kludge a pair of switches for different pinouts and two transistors in that space.
I have a really low noise Jfet that came from Quan-Tech for checking the calibration.
go to below and click on Go Advanced. then go to the paper clip symbol on the top line. It will bring up a brouser to find your scan and upload it.
Then go back to your message and click on the same paper clip and then you will find your scan... click on it and it will appear in your message.
-RNM
Then go back to your message and click on the same paper clip and then you will find your scan... click on it and it will appear in your message.
-RNM
So this is Mr. Watt Sucking Fireball at UpstairsAmps and I have two of these 5173's, one with the transistor adapter and one with a single 741 type pinout op-amp fixture. I would be interested in seeing the Quad op-amp fixture if we could get together. I'm planning on having blank module assemblies made up to facilitate testing everything and would like to see if there is any hidden trick to the quad. The single op-amp fixture is configured as a non-inverting gain of 20db and driven with the calibrate oscillator on pin 6 of the connector. I'm interested in whether the quad is set up with each amp having a resistor pair on each amp as well. the resistors on the single fixture are 100 ohm inverting input to ground and 909 ohm inverting input to output. 20 db non-inverting gain
The quad opamp fixture is really simple. The mechanicals of the fixtures is the pain. For the quad the plus input pins are all tied together and each output has its own feedback resistors with the outputs tied to each output pin on the connector. Add power supply bypass caps and you are on the air.
I used edge connectors chopped from old ISA cards for the connector. It will have the right pin spacing. Dealing with the right angle connection is more of an issue.
I could stop by on my next trip to San Jose and review my experience if you want.
I used edge connectors chopped from old ISA cards for the connector. It will have the right pin spacing. Dealing with the right angle connection is more of an issue.
I could stop by on my next trip to San Jose and review my experience if you want.
I'd be up for some comparative viewing of test fixture innards - I haven't had the time to crack the lid on mine, as I've been struggling to finish a lot of other outstanding projects. However, I'd eventually like to set up my fixture to somehow accept 3-legged critters, as I have a lot of new/NOS jfets (and a few mosfets) that I'd like to screen for noise.
5173
OK, so I figured out the secret of the conversion of a single op-amp test fixture to accomodate a dual as well. Came up with the conclusion you illustrated. plus in's tied together, 20db of gain on each amp using a 100 and 909 ohm resistor in the neg in. and a couple bypass caps. also had to add a switch to only connect a couple leads for the dual case, so it has a switch now for single or dual parts. I have a FET/Transistor adapter for the other one. For the record there are some Quan Techs here : two 5173's one 2173 with trans and IC heads, a 310 trans unit a 312 FET unit and a resistor noise unit. When I was working with Stansbury on a guarded remote for vacuum triodes I learned from him an odd phenomenen regarding the 5173 head. You cant put it on top of the readout or it causes a noise increse bump in the 1KHz readout. the head is always at ease to the left of the readout or on another plane. He thought there was a possible loop current caused by the capacitance between the two chassis and the circuit sensitivity would see it. I was able to improve the cable by wrapping it with copper screen and grounding it at both ends. Cell phones wreak havok on the readout and so should be as far away or turned off when making measurements. I have the 5173 on a copper clad bench and an isolation transformer to the AC so the chassis can be made common mode to the test bench alone. Heavy Duty Aluminum foil bonded to a bench top with contact cement or double sided sticky tape works as well. The Iso helps a lot when ultra low noise parts are being tested. Thanks for the sanity check on the Quad amp fixture, one check point is always a good thing.
OK, so I figured out the secret of the conversion of a single op-amp test fixture to accomodate a dual as well. Came up with the conclusion you illustrated. plus in's tied together, 20db of gain on each amp using a 100 and 909 ohm resistor in the neg in. and a couple bypass caps. also had to add a switch to only connect a couple leads for the dual case, so it has a switch now for single or dual parts. I have a FET/Transistor adapter for the other one. For the record there are some Quan Techs here : two 5173's one 2173 with trans and IC heads, a 310 trans unit a 312 FET unit and a resistor noise unit. When I was working with Stansbury on a guarded remote for vacuum triodes I learned from him an odd phenomenen regarding the 5173 head. You cant put it on top of the readout or it causes a noise increse bump in the 1KHz readout. the head is always at ease to the left of the readout or on another plane. He thought there was a possible loop current caused by the capacitance between the two chassis and the circuit sensitivity would see it. I was able to improve the cable by wrapping it with copper screen and grounding it at both ends. Cell phones wreak havok on the readout and so should be as far away or turned off when making measurements. I have the 5173 on a copper clad bench and an isolation transformer to the AC so the chassis can be made common mode to the test bench alone. Heavy Duty Aluminum foil bonded to a bench top with contact cement or double sided sticky tape works as well. The Iso helps a lot when ultra low noise parts are being tested. Thanks for the sanity check on the Quad amp fixture, one check point is always a good thing.