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Rohde and Schwarz AMIQ Modulation Generator Teardown

tomverbeure.github.io

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Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#11

Post by tverbeure »

avidiax wrote: post #6
raziel2701 wrote: post #5

Does anyone know what company auctions this stuff? The author doesn't say.

I had the same question. Seems the UC schools use Publicsurplus.com, but last time I looked, I didn't see anything interesting.

I bought it through edispositions.com.

Extremely good deals are rare and the chance that there’s something broken is very real. I often consider that a feature: fixing test equipment is a bit of a hobby, but be prepared to end up with a doorstop that cost a few hundred dollars.

Here are some examples that I bought though them:

- HP 8650E spectrum analyzer: works but intermittent shutdowns

- TDS 794D: works, but CRT is broken. A well know failure mode. Need to install a $75 LCD replacement.

- this R&S AMIQ: totally broken. Needed many days of work to revive.

It’s high risk buying these things.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#12

Post by tverbeure »

CamperBob2 wrote: post #2

Great disassembly job. There's yet another branch of the rabbit hole that Tom almost fell down: ... the multiplier is based on a classic form, having a translinear core, supported by three (X, Y, and Z) linearized voltage-to-current converters, and the load driving output amplifier. I have no clue how the thing works! The 'translinear' school of design was founded (or at least popularized) by Barrie Gilbert at Analog…

That’s for that info! I’ll give that links a good read.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#13

Post by tverbeure »

Junk_Collector wrote: post #9
jandrese wrote: post #7

Earlier quoted context omitted.

R&S equipment is pretty common in the cellular industry. There is more of it out there than you would think. While this particular signal generator is maybe not the most common piece of equipment you will see lots of R&S spectrum analyzers and the like.

It's technically not a signal generator but an Arbitrary Waveform Generator. It provides a base-band modulated signal to the signal generator which the sig gen upconverts to the RF carrier. If you purchased a Vector Signal Generator this would be built in but you can still buy them stand alone and they are pretty common. NI, R&S, Tek, and Keysight all have product lines of them. Another way to think about it, this wo…

What you call a signal generator is what most would call an RF signal generator. Both an AWG and an RF signal generator belong to the generic signal generator family. :-)

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#14

Post by myself248 »

raziel2701 wrote: post #5

Does anyone know what company auctions this stuff? The author doesn't say.

You'll find whole labs full of it once in a while on Bidspotter, set a saved-search for some names like Rohde and Tektronix and Keysight and you'll get emails once in a while.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#15

Post by myself248 »

I'm amused that it's just a PC motherboard, and that it uses ISA to talk to the generator hardware itself. Makes perfect sense; nothing needs high data rates there, and it's really easy to interface with. I just wouldn't have necessarily predicted it before seeing the case open.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#16

Post by teleforce »

Wonderful article and I don't even know that this device existed perhaps due to Agilent/Keysight bias laboratory/shop.

R & S AMIQ Modulation Generator general specs is available here [1].

Fun facts, the venerable Silicon Valley was started by Hewlett-Packard (HP, then Agilent, now Keysight) that mainly supplying function/signal/waveform generator for the then booming radar and electronics industry.

HP Garage is now a designated landmark and marked with a plaque calling it the "Birthplace of 'Silicon Valley' " [2].

[1] Rohde & Schwarz – AMIQ04 I/Q Modulation Generator:

https://testworld.com/product/rohde-schwarz-amiq04-iq-modula...

[2] Hewlett-Packard:

https://en.wikipedia.org/wiki/Hewlett-Packard

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#17

Post by dusted »

I'm trying really hard not to want to turn this into a dac for my stereo system. They build really nice boxes..

I have a PSL-3 industrial controller (well, two, but one is broken) on the shelf behind me that I'm using for the noble purpose of playing Theme Hospital in Windows 98.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#18

Post by lnsru »

myself248 wrote: post #15

I'm amused that it's just a PC motherboard, and that it uses ISA to talk to the generator hardware itself. Makes perfect sense; nothing needs high data rates there, and it's really easy to interface with. I just wouldn't have necessarily predicted it before seeing the case open.

Many modern measurement hardware is built this way - motherboard with custom PCIe boards. It dramatically simplifies GUI design using standard tools and keeps the complexity separated on the external boards. The PCIe boards also can be designed for one/two measurement channels making the equipment rather modular and customizable.

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#19

Post by myself248 »

lnsru wrote: post #18
myself248 wrote: post #15

I'm amused that it's just a PC motherboard, and that it uses ISA to talk to the generator hardware itself. Makes perfect sense; nothing needs high data rates there, and it's really easy to interface with. I just wouldn't have necessarily predicted it before seeing the case open.

Many modern measurement hardware is built this way - motherboard with custom PCIe boards. It dramatically simplifies GUI design using standard tools and keeps the complexity separated on the external boards. The PCIe boards also can be designed for one/two measurement channels making the equipment rather modular and customizable.

Yeah, but PCIe is a bit harder to DIY an interface for! ;)

Re: Rohde and Schwarz AMIQ Modulation Generator Teardown

#20

Post by HeyLaughingBoy »

lnsru wrote: post #18
myself248 wrote: post #15

I'm amused that it's just a PC motherboard, and that it uses ISA to talk to the generator hardware itself. Makes perfect sense; nothing needs high data rates there, and it's really easy to interface with. I just wouldn't have necessarily predicted it before seeing the case open.

Many modern measurement hardware is built this way - motherboard with custom PCIe boards. It dramatically simplifies GUI design using standard tools and keeps the complexity separated on the external boards. The PCIe boards also can be designed for one/two measurement channels making the equipment rather modular and customizable.

A lot of hardware is built like this. Separating the GUI from the real time or safety-critical aspects of the system is a common enough need that there are many System-on-Module (SoM) boards that can run Linux or Windows and also include an ARM processor for real time behavior on the same die.

Your UI can be built in Python/Qt/Tk while the safety critical stuff is programmed in C running on an RTOS.

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