Would a tracker like the one in 1960s spy movies be possible?

[Skipper]

I was seeing this scene in an old episode of Mission Impossible (but you've probably seen it in many other films of the time). Our heroes stick a box the size of a cigarette pack on the bad guys' car. Then our heroes manage to follow the villains' car to some device, where a red dot moves on a map. Obviously I know it's a fiction, but I wonder, before GPS, would such a device have been theoretically possible? I imagine maybe something that fired a continuous pulse on a certain frequency, but this pulse would have to be triangulated by at least two antennas right? And I wonder what the precision of such a device would have been.

 

[Santaman]

Of course in movies you have the exact accuracy you need by plot.. there were all kinds of radio triangulation methods, might be even one with the desired accuracy.
https://en.wikipedia.org/wiki/Direction_finding

 

[publiusr]

You might get away with that more easily in the western states or Australia where there aren’t as many cars.

Even today, some can be quite large…and these are used more frequently than you might imagine:
https://abcnews.go.com/amp/US/california-student-finds-fbi-tracking-device-car/story?id=11841644

Repo men use them all the time:

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You can fight back:
https://arstechnica.com/tech-policy...-device-from-your-car-isnt-theft-court-rules/
https://spy-spot.com/blogs/news/how-to-find-and-disable-a-gps-tracker-on-your-car

Repo men will take your car if you don’t make the last payment if you are sick or hurt just like they’d grab it if you never made the first payment.

The best evasion is getting a contact out of state to get a car you like and vice versa…and swap as soon as the black boxes are trashed.

The repo men will be helpless.

 

[XCV330]

This is what 1960's radio direction finding equipment looked like:
https://www.rigpix.com/specialized/heathkit_df1.htm

There were more advanced things like the ADF-940, that governments had access to, but they were mostly stationary. The link above would have been used for radio fox-hunting (I think it was called something to the effect of radiosport in eastern Europe where it was more popular). I did radio fox hunting, just a little, in the 90s. By then we had hand-held radios, hand held yagis and strength meters. It could take all day to find the hidden transmitter, even worse if the person hiding it had put it under a bridge or culvert.

 

[publiusr]

Loops sticking up out of vans then?

My uncle had a ratcheting dial that would turn the antenna atop his house.

 

[XCV330]

Loops sticking up out of vans then?

My uncle had a ratcheting dial that would turn the antenna atop his house.

I had one of those for my old tribander quad. My folks had one for the TV antenna atop their house. Lately I don't have any kind of permanent outdoor antenna setup. I'm in a bit of transition at the moment. I will, hopefully, be taking novice vows as a Franciscan this summer, and well.. time to simplify! So I'm getting rid of things, including a lot of old radio hardware.

I directional loop might work, though got VHF/UHF radio direction finding I generally saw people use small handheld Yagis. At microwave freq's you could probably use a parabolic dish, or even a cheap horn antenna brazed from double sided circuitboard attached to the feedhorn and whatever you were using for a receiver (some kind of IF mixer going to a broadcast fm receiver back when 10ghz stuff was in its infancy. I am sure people have much better gear now, but I no longer know what is state of the art. Such is life. )

 

[publiusr]

Being colorblind, it all looked like spaghetti to me…the wires.