Design Time Domain Reflectometer (TDR) to Sell, New Startup

Electronics
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All right everybody. I’m feeling ambitious, and this is a project I have been wanting to do for years. Run a quick google search on TDR to understand what one is if you don’t already know.

Bottom line is this: I want to make a high end dual channel TDR with specs that improve upon the instruments on the market. Note that some of these instruments are very expensive. I see about $300 to $20000 price tags for a TDR. Now this may seem like an overly ambitious project. Well, its not as tough as you might think. I have made three prototypes through the years, and now I am ready to go pro.

The TDR I envision developing will be much more flexible than any of the instruments I see online, and will cost much less to make, so I’m expecting some healthy margins. Also, I have some special connections, a partnership with a very large respected instrumentation company that I have a good idea will help promote it if we can build it.

I want to spin it into a business, and there are many differing form factors and target platforms I want to plan to interface with. I believe that with some effort, this has a good chance of becoming a new instrumentation company. The best companies started in garages, we have makerspace!

I am comfortable designing the mixed signal front end of the device, but would be happy to distribute the work as there will be plenty of it. Now here is the kicker, I will also distribute ownership percentages in the company to those who contribute their time and energy. There are pieces I will need help with (mechanical enclosure for starters), but you don’t have to be an expert to grab a piece of this startup. I am happy to share my knowledge. And I am hopeful that we will find the answers to the portions of this design that I will need help with.

Here is a very rough listing of what needs to be done:

-competition comparison matrix
-crowdfunding? other sorts of funding help
-specifications
-electronic front end component evaluations
-selection of PCB fabrication facility (hopefully with design entry and layout capability)
-power supply design
-actual PCB design
-bring up/debug
-mechanical enclosure
-cabling selections
-software development
-firmware development
-test system development
-company website
-marketing
-sales

Now I am sure I am missing quite a bit, but as you can see, there is a lot to this. I need help if I want to get this to market quickly, which I do. I am comfortably experienced with mixed signal circuit development, software development, cabling, test system development, Ive even written a couple wordpress and dreamweaver sites in my day. But I would love to have some help with this one. I think if we can pull it off, we will find it to be quite lucrative.

If you have never done anything like this before, relax, neither had I the first time I did it. You can learn about electronic hardware development AND become co-owner of a technology startup if you want to buddy up with me and help figure this one out.

So I am hoping to set up a class soon to see who all is interested in this concept, but I thought I might write into here first to guage interest level. I need to do this project for a whole lotta reasons, but I really would like to share some knowledge I have accumulated over the years, and I also would like to show the world what is possible in a place like Makerspace.

Does this sound interesting to anyone?

Of course I can help mentor anyone wants to learn about mixed signal PCB design. And I need help with mechanical enclosure, marketing, website, and a whole bunch of other stuff. Even you are not that skilled but interested, let me know your interest level, as I am happy to work with anyone daring enough to roll with me on this ambitious but do-able project and company development.

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Oh, and here are a few more items for the list:

-technical publications
-packaging for sales
-UL listing, emissions testing, safety testing, electrical interference, static, etc.
-other testing-shock & vibe,

…there is more, this onion will shed layers for a minute, hence the request for help…

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I also want to clatify what a TDR is:

It started out being a method for detecting cable faults on maybe a telephone line or a power line. The idea is that with a certain source termination, when you apply a rapidly changing voltage across the input terminals to the cable (2conductor) which isopen at the far end, at two times the propagation latency of the cable, a reflection will arrive at back at the end of the cable where the voltage change was applied.

So if you cut the cable shorter, the ‘reflection’ would come back sooner. In fact, if you measured the time it takes to get reflection back, then /2, you can determine where the break in the cable is. Pretty useful if it’s a buried cable, huh?

So now, various folks have made all sorts of variations upon this notion creating TDRs, Differential TDRs, TDTs, etc. It turns out that you can extract all sorts of info about all sorts of circuits (not just cables) using the iDea behind TDR.

So I want to srart a production of TDRS business, and I need help from anyone willing to work for slice of ownership. BTW, TDRS are quite pricey. It’s good to be in businesses with pricey products.

1 Like
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Here is a new idea for excitation for TDR direct from National Instruments website. Traditionally, Ive seen edges/pulses, half sine tones, even durac fucntions used as stimulus applied at cable end. But check this out:

Overview
This example shows the application of the Time Frequency Analysis VIs in Time Domain Reflectometry (TDR). A TDR is an instrument that characterizes and locates faults in cables. You can transmit a chirplet along a cable and receive the reflected signal. The reflected signal also is a chirplet but has different time center, amplitude, and others. You can characterize and locate faults in the cable based on the difference between the transmitted chirplet and the reflected chirplet. A TDR signal contains both the transmitted and the reflected chirplets. One of the challenges in the applications of TDR is how to separate and extract parameters of the transmitted and the reflected chirplets. This example simulates the TDR signal from a cable and uses the TFA Adaptive Transform VI to extract the parameters of these two chirplets. This program is a shipping example VI included with the Advanced Signal Processing Toolkit for NI LabVIEW.

This software is written in LabVIEW, a graphical programming language designed for scientists and engineers. For more information about LabVIEW, visit What is NI LabVIEW? Graphical Programming for Test & Measurement - NI.

Advanced Signal Processing Toolkit Example Programs
The National Instruments Advanced Signal Processing Toolkit is a suite of high level VIs, libraries, software tools, example programs, and utilities for time-frequency analysis and digital filter design. With this toolkit, you can experiment and develop with modern analysis techniques that include wavelets, super resolution (model-based) spectral analysis, and joint time-frequency analysis (JTFA). Also included is the National Instruments LabVIEW Digital Filter Design Toolkit, which allows you to interactively design and characterize finite impulse response (FIR) and infinite impulse response (IIR) filters.

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