×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Modulating 10 GHz motion detector for Amateur Use

Modulating 10 GHz motion detector for Amateur Use

Modulating 10 GHz motion detector for Amateur Use

(OP)
I want to get started with 10 GHz communications with custom made gear. Looking at the schematic for the C900503 10.525 GHz planar transceiver this looks possible.

Spec Sheet: http://pdf1.alldatasheet.com/datasheet-pdf/view/33...

As far as I can understand , the only think needed for a modulator to work is a change in voltage across a varactor that is in the same mechanical cavity as the dielectric resonant oscillator.

I think having the transmitter as the local oscillator also simplifies things. If I get two of these module linked together they can occupy two channels for full duplex communications.

What would be the most efficient way for me to make a modulator for this specific transmitter?

RE: Modulating 10 GHz motion detector for Amateur Use

Hi. Your thread title includes "Amateur" with a uppercase A, so I presume you mean Amateur (Ham) Radio. Last time I checked, the Amateur X band allocation was 10.000 to 10.500 GHz. The 10.525 GHz gadgets are just outside the Ham allocation. You can double check my recollection if you wish.

Of course, the 10.525 GHz devices are already on a licence free assignment, so you can probably still use them within reason. It's usually designated for Field Disturbance equipment, include Doppler effect door openers, and police X band traffic radar.

Modulating wideband FM for Transmit is very straightforward. Detecting at the Receiver end is slightly more complicated.

There should be plenty of example circuits on the Internet already. Ideally, you might want to also retune below 10.500 GHz.

I'll search around and see if I can find any examples.

Disclaimer: I never progressed past On-Off keying with my Gunn diode Doppler door opener. Used a commercial radar detector at the other end.

RE: Modulating 10 GHz motion detector for Amateur Use

I've reviewed the linked data sheet. Similar gadgets are on eBay for several dollars. Search: 10.525 GHz

You could try imposing the signal onto the power supply. If the device includes a built in voltage regulator, then impose the signal after the regulator. The required input might be tiny, so start very low. Watch the limits.

I'm not sure it's feasible, but it probably is. For $3, that's what I'd try first.

Keep in mind, you don't necessarily need much deviation. Even a few kHz (on 10.5 GHz) might (?) be sufficient, depending on your project.

RE: Modulating 10 GHz motion detector for Amateur Use

(OP)
Thank you for the information VE1BLL. People are telling me that I can use a cheap FM broadcast radio as the IF receivier and that the AFC would prove helpful.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper - The Evolving Landscape of Commercial Battery-Powered Trucks
What’s driving the evolving landscape of truck electrification? What are the barriers, motivators and strategies for accelerating the electric transition? What insights and resources are available for today’s design engineers working to achieve industry disruption and evolution? For answers to these and other pertinent questions, read this white paper. Download Now
eBook - Rethink Your PLM
A lot has changed since the 90s. You don't surf the Web using dial-up anymore, so why are you still using a legacy PLM solution that's blocking your ability to innovate? To develop and launch products today, you need a flexible, cloud-based PLM, not a solution that's stuck in the past. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close