Back in the '60s and early '70s I did some work with Impatt and Gunn diodes,
building a little self-detecting doppler for speed sensing. However, 35
years have passed and my notebooks for that stuff are somewhere in a dusty
archive along with my venerable sliderule.

Is there a cheap source for onesies-twosies of a radar front-end that will
give me doppler audio as a function of a large metal object's speed at a
range of 20 meters or so? I don't need to go into production on this thing,
just build one. A surplus source would be ideal.

It seems that the little kids on our rural country lane have all become
teenagers at once and are trying to outdo the others in how fast they can
drive daddy's car up and down the lane. We've lost one dog this week and
unless I can put up some sort of a siren that goes off when they exceed some
agreed upon limit, the carnage will continue.


Regards,


Jim

RST Engineering wrote:

Back in the '60s and early '70s I did some work with Impatt and Gunn diodes,
building a little self-detecting doppler for speed sensing. However, 35
years have passed and my notebooks for that stuff are somewhere in a dusty
archive along with my venerable sliderule.

Is there a cheap source for onesies-twosies of a radar front-end that will
give me doppler audio as a function of a large metal object's speed at a
range of 20 meters or so? I don't need to go into production on this thing,
just build one. A surplus source would be ideal.

It seems that the little kids on our rural country lane have all become
teenagers at once and are trying to outdo the others in how fast they can
drive daddy's car up and down the lane. We've lost one dog this week and
unless I can put up some sort of a siren that goes off when they exceed some
agreed upon limit, the carnage will continue.


Regards,


Jim





Yep they are available. I have about a dozen or so of Gunn units that
came from
10 GHz door opening bits They have the Gunn diode and a detector diode.
The rest of the
electronics I threw away.

Two of them can be sent for the cost of postage.

Bill K7NOM

Bill Janssen wrote:

RST Engineering wrote:

Back in the '60s and early '70s I did some work with Impatt and Gunn
diodes,
building a little self-detecting doppler for speed sensing. However, 35
years have passed and my notebooks for that stuff are somewhere in a dusty
archive along with my venerable sliderule.

Is there a cheap source for onesies-twosies of a radar front-end that will
give me doppler audio as a function of a large metal object's speed at a
range of 20 meters or so? I don't need to go into production on this
thing,
just build one. A surplus source would be ideal.

It seems that the little kids on our rural country lane have all become
teenagers at once and are trying to outdo the others in how fast they can
drive daddy's car up and down the lane. We've lost one dog this week and
unless I can put up some sort of a siren that goes off when they exceed
some agreed upon limit, the carnage will continue.


Regards,


Jim





Yep they are available. I have about a dozen or so of Gunn units that
came from
10 GHz door opening bits They have the Gunn diode and a detector diode.
The rest of the
electronics I threw away.

Two of them can be sent for the cost of postage.

Bill K7NOM
I suggest modifying a readily available sports radar, it is very sensitive,
outputs speed digitally and is inexpensive.
--
JosephKK

RST Engineering wrote:
It seems that the little kids on our rural country lane have all become
teenagers at once and are trying to outdo the others in how fast they can
drive daddy's car up and down the lane. We've lost one dog this week and
unless I can put up some sort of a siren that goes off when they exceed some
agreed upon limit, the carnage will continue.

I realize this is way off the subject, and I do honestly wish you
success in getting the neighborhood speed demons under control, but...

as a bicyclist, I find it necessary to point out... that if the
neighborhood dogs are being hit by speeders, those dogs are obviously in
the road. They shouldn't be.
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

Neither should little kids, but poo happens. With dogs it's "I'm sorry".
With kids it's manslaughter.

Jim



"Doug Smith W9WI" wrote in message
...

as a bicyclist, I find it necessary to point out... that if the
neighborhood dogs are being hit by speeders, those dogs are obviously in
the road. They shouldn't be.
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

Hello Jim,


Neither should little kids, but poo happens. With dogs it's "I'm sorry". ...


Not necessarily. It can become wrongful death but you'd have to have
proof of grossly excessive speed. Skidmarks can be such proof if a car
doesn't have ALB. But, of course, the experts for that usually only come
out when a person has been hit.

Regards, Joerg

http://www.analogconsultants.com

"Joerg" wrote in message
. net...
Hello Jim,


Neither should little kids, but poo happens. With dogs it's "I'm sorry".
...


Not necessarily. It can become wrongful death but you'd have to have proof
of grossly excessive speed. Skidmarks can be such proof if a car doesn't
have ALB. But, of course, the experts for that usually only come out when
a person has been hit.

Regards, Joerg

No idea what you mean by ALB as abbreviations are only good for those who
all have an understanding of what is meant.
If you refer to a car with antilock brakes then they DO leave marks that can
be identified. I have investigated enough accident scenes that leave the
same tell tale signs. Boy racers with antilock brakes all assume they can
go faster and no one will know. How wrong they are.

Hallo Brian,


No idea what you mean by ALB as abbreviations are only good for those who
all have an understanding of what is meant.


I used ALB because it was on the insurance papers. They give a discount
for that feature. In Europe they mostly call it ABS.


If you refer to a car with antilock brakes then they DO leave marks that can
be identified. I have investigated enough accident scenes that leave the
same tell tale signs. Boy racers with antilock brakes all assume they can
go faster and no one will know. How wrong they are.


True, they do leave regulation patterns. But an accident investigator
told me they are pretty faint and wear off faster by traffic.

Regards, Joerg

http://www.analogconsultants.com

"RST Engineering" wrote in message
...
Neither should little kids, but poo happens. With dogs it's "I'm sorry".
With kids it's manslaughter.

Jim



"Doug Smith W9WI" wrote in message
...

as a bicyclist, I find it necessary to point out... that if the
neighborhood dogs are being hit by speeders, those dogs are obviously in
the road. They shouldn't be.
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com



RESPONSIBLE parents do not let their children run out in the road, idiots
that allow dogs to run free in the road need to be aware that they can cause
accidents. I do hope the pathetic owner is held responsible when a dog
which is out of control runs out and causes an accident.
Two seperate arguments, you need to be clear of what it is you want.
Jealousy is a terrible thing, so if that's all it's down to then give up.
That is wht it comes across as. The people concerned probably have their
own cars and don't expect some idiot to allow a dog to run infront of them
in the hope they will hit it. Were you after an insurance claim?
Keep the dogs under control as responsible people keep their children under
control.

Hello Brian,


Keep the dogs under control as responsible people keep their children under
control.


Even then it can still happen and we all have to use our cars carefully.
One kid didn't get injured because I was going 15mph in a 25mph zone
(the street where we live). It dashed out when the garage was opened,
zooming into the road from behind a van. Couldn't see it coming but I
never go faster on that street, for that very reason. I came to a stop
about one foot before the child.

Regards, Joerg

http://www.analogconsultants.com