Aybody have a good reference/tutorial on noise and double balanced mixers?

Random Google hits that look interesting:

Try the old HP AppCAD 3.0.2 as a sanity check: Signals-Systems -> NoiseCalc

You can plug in models of various mixers, fill in the boxes with some specs, wrap the mixer with isolation amps, and see the effect of NF on the entire receiver system. It's not exactly what you're asking for, but I think you'll find it useful.

Wes Hayward, "Introduction to Radio Frequency Design", Prentice Hall,

There's lots of different kinds of double balanced mixers. I don't know much about the others, but a diode ring mixer basically does nothing to the noise, but cuts the signal amplitude by a factor of 2. So it adds

Am 14.04.2014 06:34, schrieb RobertMacy:

regards, Gerhard

Gerhard,

THANK YOU! That's a great piece of literature from Cornell University.

Suspected that what is described in the noise section, Section 9, was EXACTLY what was happening to me: folding multiple spectral noise contributions into the mix. But I have to say, the author laid it out much better.

thanks!

Thanks, only 14MB and runs on a 'range' of Windows OS's.

Looks like a handy tool for making presentations, too.

Thanks for the reference.

Diode rings generate EVERY ODD harmonic of the carrier, which because they do NOT get filtered out, will get in the way. I know, I know. People give a solution and I respsond with, "Oh, thre's one more thing" I hate that too. Then again, *if* diode rings can be used, they have to be cheaper/simpler, maybe there's still some way to do that. Thanks for the 'food for thought'

Am 14.04.2014 16:14, schrieb RobertMacy:

You may also be interested in his book and search his web site.

cheers, Gerhard

website URL? ...didn't find it at the Amazon URL

...DOT_de_ ...Jim Thompson

Am 14.04.2014 18:10, schrieb RobertMacy:

Enter "Enrico Rubiola" into google and the first answer is:

;-) Gerhard

Thanks. Quite a website, will have to look through the 'available' literature.

I use it a lot for PCB trace impedance calcs. It doesn't do differential pairs, so I use TXLINE for those.

tried this?

-Lasse

I don't recall you mentioning exactly what you're up to with this mixer, other than you wanted it to work in both directions.

I do know that most mixers give better dynamic range (defined as the dB change in a signal that ranges from the noise floor to unacceptable distortion) when they're driven with a square wave, or hard enough that the carrier may as well be a square wave.

If it's a radio, there's ways around that -- usually the way around that is to filter the incoming intended signal with a filter broad enough to catch a whole band, but narrow enough that you don't get spurious mixing products of either noise or unintended signals. Then you amplify that in the RF and apply the result to the mixer.

But you've got a specific idea in mind, and I don't know whether the above helps or not.

Wow! pure gold! thank you.

Any of Amazon loads me down with tracking cookies and pictures upon pictures that don't allow me to use the PC while Amazon deems themselves more important. These websites are like having a nagging child keep taking your attention away. Just enough 'pause' to irritate, but not enough to cause killing it, euphorically, or is that euphemistically?

Private note: any progress on getting a sample mixer problem for me to analyze using my .tranoise feature? Heopfully, smallish in size.

Every bit helps. At the risk of hijacking my own thread...True that a long time ago I learned the hard way that the best way to reduce noise in a digital system is to make it faster, more abrupt, which was EXACTLY the opposite from quieting down analog systems. Analog systems add a cap, but add a cap in digital and you have major problems, rather speed up the transitions and there's less time for the logic gates to 'think' about it. Thus, probably a quiet mixer will be one that makes super fast transitions from full ON to full OFF, like a diode ring. From looking at the NF's seems to be correct. see a few with NF=7.5dB and some an incredibly low

I'll try to make time to find something you can use. I'm heavily loaded at the moment. ...Jim Thompson

Also runs on Linux under WINE.

I've done that, but using slides, not the actual program. I use AppCAD mostly for calculating receiver gain distribution and the IP3 calculator.