RFDesign Magazine article--Tayloe

Indeed. I think a lot of people (including myself) come up with the idea behind the Tayloe detector independently... and in my case I can attribute it to some Forrest M. Mims book I read back in the '80s (he was applying the idea to modulators instead of demodulators though)...

Further discussion of Tayloe's detector not being all that horribly new:

---Joel Kolstad

I'm looking at info on the Tayloe detector, I have found the article below, however, the article is missing the figures. Anyone know how I can get them, or does anyone have them to send me.

Thanks Mike

I've been out of the receiver design game for about fifteen years, concentrating on audio processors and some other stuff (like keeping at least a week ahead of my college students).

Tell me, in a VHF AM double sideband world, how do you implement a zero-IF receiver? Seems to me that if the on-frequency "local oscillator" needed to be spot on the carrier drifted just a few hundred Hz. that it would show up in the detected signal as a howling audio tone. I guess you could implement a phase-lock arrangement of some sort, but phase locking to submicrovolt signals ain't all that trivial.

At this point, just of academic interest, but I hope to retire out of academia next year and would really like to get my hands back on the design bench. It's been too long ...

(So? What was WRONG with the 6U8 mixer design?)

Jim

In a receiver, it's better to decimate against a frequency that brings the image down to a low IF, rather than a zero I.F., to avoid the DC offset issue and to improve the dynamic range of the detector. In this case, the absolute value of the IQ vector sum (after low-pass filtering) is the AM demodulated output. For phase demodulation, the offset must be subtracted from the result.

For a transmitter, offset is introduced for a different purpose, usually to prevent injection locking of the VCO with the modulated carrier.

Frank Raffaeli

What means "decimate"???

against a frequency that brings

Well, shucks, that's just a single conversion superhet.

In this

Are you saying then to use a zero-IF to detect the first IF?

Jim

This reminds me of a dozen years ago when I was an engineer at Texas Instruments.... I was on the Patent Committee , and it was our job to review the NUMEROUS invention disclosures that were submitted by several hundred engineers in order to determine which ones would be useful to the company to file.....

Much of the time, the "invention" would be something that one of us had used 20 years before, and could now be bought from Digikey or Newark for a couple dollars from their catalog........ These , of course, were not approved for filing, and caused great disappointment to the inventors, who were very proud of their GREAT IDEA....

In fact, most of the ideas were GOOD IDEAS, .... it's just that someone else had them before, and , while that doesn't diminish the intellectual kudos for the new inventor, it did mean that filing for a patent was of no use, since it was prior art...... You need a lot of old-timers who are also electronics hobbyists on a patent committee to weed out this stuff......

So, let's don't "dis" Mr Tayloe -- he had a good idea, and may have come up with it on his own...... Just like the other guy did 20 years ago...... It shows he is a , thinking, innovative person....... sometimes you eat the bear, sometimes the bear eats you....

Andy

PS My first patent application, ( a half century ago ) was for a T notch filter which used a transistor as a feedback emitter follower. It was denied because, 30 years earlier, a fellow had done the same thing with vacuum tubes........ I was disappointed, of course, since a person's "first " patent is the one which validates his personal sense of innovative genius. I recovered, and had a nice career in spite of it.......... .......... end of nostalgic reverie ........

You take a stream of numbers and insert a bunch of zeroes inbetween them. :-)

Seriously, that's what you do. It 'squishes' (compresses) the frequency response... see something like section 9 of

Tutorials/450968421DDS_Tutorial_rev12-2-99.pdf, your favorite DSP book, Google, etc.

[snip]

I was on Motorola's and GenRad's patent committees.

I have that as a wood placque over my office door ;-)

I've only had one patent application where the examiner tried to deny it. I replied he was too dumb to understand the concept. He then allowed it ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

Hello Jim,

They employ two balanced mixers in an I-Q structure. Sounds easier than it is in reality. In theory none of the LO energy gets out. In reality some does. Then it produces the effect you mentioned or, worse, gets modulated and re-radiated somewhere and then brings in a nice 120Hz rattle.

Here is a paper on it:

Nothing wrong with these, except that right now I am happy that there is no tube heating up the office. I don't like AC in there so it's a cozy

96F. The ECC81 was my favorite and you could make a nice balanced mixer with these. With a dynamic range from here to Alaska.

Regards, Joerg

Hello Jim,

Many patents seem to be written to build a thick portfolio. When drilling down the claims it often takes less than 1/2 hour to find serious prior art that would potentially blow it out of the water.

Regards, Joerg

Hello Andy,

My personal sense of innovative genius gets validated when the client is happy, made money with it, and I made money with it ;-)

Regards, Joerg

I've served on one of these "boards" for twelve years. It's quite interesting to see how inventors think. It's also quite interesting to see what motivates the best of them. It's not what I would have expected a decade ago. ;-)

Wooden plaque! Ick! Does your dentist know?

Times have changed. Now they're all too dumb, but must reject them anyway. The USPTO is now a government profit center and rejections make them more money (think: performance reviews).

--
  Keith

I also went looking for the figures (pretty sure it was the same article). Dan Tayloe was good enough to send me an earlier manuscript

- I think I found him on rec.radio.amateur.homebrew.

Steve Kavanagh

amdx wrote:

On 20 Jul 2005 14:33:31 -0700, "Andy" wrote:

My name is on two patents, and other than actually contributing to the design covered by the patents, I had very little to do with it (If that sounds clear as mud, I hope my explanation below clears it up). I'm sure I'm a thinking, innovative person, unfortunately that has little to do with my name being on these patents. My employer at the time, a quite large company, said they wanted another patent (which quickly became two patents), and it was going to be on the product I was co-designing. The managers talked to the patent attorney, then tje attorney talked to the other engineer and me for a couple of hours, asking us about the operation of the areas to be covered by the two patents. What was being applied for had already been determined by the managers. Between the other engineer and myself, there were about half a dozen OTHER parts of the circuit or methods of operation of the device that we would have chosen one or two to be patented (had we been asked). We would not have thought of what was being proposed for the patents. But to management it wasn't so much about protecting innovative ideas as it was about the company cutting out as big a turf of IP as it can for each patent, so that it is more likely to find competitors' products infringing. As was explained to me, this is done as much in defense as in offense: If another company finds one of our devices infringes, if we have enough patents so that we can find where they infringe one of ours, we can cross-license the patents to each other and go on like nothing happened. A few months later the attorney sent a draft of the application for us to comment on. We changed a couple sentences and sent it back. About a year or two later I got this blurb in the mail saying "Congratulations! For only $65 you can get the first page of your patent application with the date it was approved on this extra-nice plaque!" A couple months later I learned the same way that the second patent was approved.

Before all this happened, this company had a seminar on patents, describing some of the ones they had, from the usual things to business method patents. The one I most remember was where an engineer patented the addition of a resistor to a circuit when this was obviously not a big innovation - he was telling his manager he though it would be approved, the manager didn't think so but let him apply for it, and of course it WAS approved. So yes, you CAN get a patent on virtually anything, but of course enforcing something like that is another matter.

-----

adding zeros and lowpass filtering is upsampling or interpolation, lowpass filtering and removing sample is downsampling or decimation ....

-Lasse

yep, I know atleast on company very much encourage employes too try a get patents on pretty much anything they can come up with to meet they annual gold of filing atleast as many patents as the competition and give bonuses for every patent filed...

-Lasse

Could you post it on a.b.s.e.?

--
 Thanks,
    - Win

But he WAS too dumb. It was the Sample and Hold circuit done using tri-stateable PECL.

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

| 1962 | I love to cook with wine. Sometimes I even put it in the food.

Not on MY copy ;-)

Free to me because I was an author, but the flyleaf says $16.50.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.