Bob Pease of National Semi mentioned a ONE AND ONLY transistor circuit
above/under voltage rail converter (with detailed theory). I cannot remember
the details. But interesting if sometime a slightly voltage behind the power
rail is needed. For example to power a CMOS Opamp now doing rail-input.

- Henry

In article ,
Henry Kiefer wrote:
Bob Pease of National Semi mentioned a ONE AND ONLY transistor circuit
above/under voltage rail converter (with detailed theory). I cannot remember
the details. But interesting if sometime a slightly voltage behind the power
rail is needed. For example to power a CMOS Opamp now doing rail-input.

For a good discussion of Bob Pease's "April Fool" negative voltage
generator, see:

http://www.edaboard.com/viewtopic.php?p=423522

Unfortunately you have to log in to the site to see the drawings & photos.

I don't think it produces nearly enough current to power an opamp.

When I was a teenager and my brothers started bothering me with their loud
TV, I took a 220V relay, put one of the coil leads through its normally
closed contact group, and plugged the relay into the mains behind the wall
where the TV was. Made an exelent TVI/RFI generator, I thought the TV is
going to blow up.


"Henry Kiefer" wrote in message
...
Hi all -

After my first thread going from "standard" cheap parts for up to vhf
frequency to a discussion about the usefulness of Spice simulator...... I
try it another time hopefully get attention of frustrated co-readers:

For example the rechtifier diode 1N4007 can be used as a rf switching
diode,
for example as rx/tx-switch. This is because it is a pin structure diode.
This type is cheap and you can get it almost everywhere. It shows good
performance for the price. Surely for high-end you should do it with
another
type tuned to the application it is made for. But anyway it works in some
circuits.

Do you know of other interesting devices or circuits good for misuse?

Best regards -
Henry

In article ,
Ivan Makarov wrote:

When I was a teenager and my brothers started bothering me with their loud
TV, I took a 220V relay, put one of the coil leads through its normally
closed contact group, and plugged the relay into the mains behind the wall
where the TV was. Made an exelent TVI/RFI generator, I thought the TV is
going to blow up.

#chuckle#

Back when I was living in a college dorm, the guy in the next room had
pretensions of being a musician - specifically, a drummer. His way of
"practicing" was to turn up his stereo - really loud - so he could
feel the bass, then put on headphones (so that the highs wouldn't hurt
his ears) and then drum along with the music.

Needless to say, this did not make him popular with me or my roommate,
the people on the other side of his room, or the folks downstairs (or,
I suspect, people in the next county). Numerous complaints were filed;
he kept on drumming.

The guy on the other side realized that the drummer's stereo was
plugged into an outlet on one side of their shared wall, and that he
had an outlet on the same circuit. The next time the booming started
up, he plugged his old fluorescent desk light into the outlet, and
then started vibrating his thumb on the pushbutton make/break "start"
switch.

BRRZZBuzzzBZAP.

Stereo goes off suddenly. Two minutes of blessed silence. Stereo
goes back on and the drumming starts again.

BURZZRfffBUZZT.

Lather, rinse, repeat. Eventually, the drummer gives up for the day.

I understand that the drummer never did figure out what was wrong with
the stereo, despite two trips to the repair depot. He left the dorm
at the end of the quarter (I suspect he was "asked" to depart by the
Powers That Be) and we could sleep and study in peace once again.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Many years ago, I lived on the 2nd floor of a 3-story apartment
building. A guy moved in above me who worked some strange shift such
that he generally slept during the day, and at night, when the rest of
us were trying to sleep, he'd blast his stereo until the early dawn. I
tried reasoning with him a few times, but when it became evident that he
didn't care about anyone but himself, I decided that he needed a taste
of his own medicine.

I wired up a 555 timer, a driver transistor, and a 12-volt solenoid that
I had harvested out of an old VCR. The body of the solenoid was fitted
with a couple of alligator clips, so that the coil could be attached to
grill of a heating duct near the ceiling of my apartment. Every half
minute or so, (adjustable with a pot) the timer would fire and the
solenoid would contract, making a loud, obnoxious ker-chunk that
resonated through the furnace duct.

Whenever I left the apartment for work, I'd install the gizmo on the
vent, and let it run all day while the guy upstairs was trying to sleep.
The beauty of it was that the guy above could not complain about
anything I was doing, he could only complain that the "furnace was
making strange noises" that kept him awake.

A couple of times the management asked to inspect my furnace, and of
course, I let them. Needless to say, the gizmo was turned off and had
been removed from the vent in preparation for their visit.

Eventually, in true Pavlov-ian fashion, the guy upstairs learned that
the strange "furnace noises" seemed to coincide with the abuse of his
stereo. He noticed that when his stereo kept me up at night, the
"furnace" kept him up during the day. Hmmm..... An unspoken
understanding was reached and everyone lived happily ever after.



Dave Platt wrote:
In article ,
Ivan Makarov wrote:


When I was a teenager and my brothers started bothering me with their loud
TV, I took a 220V relay, put one of the coil leads through its normally
closed contact group, and plugged the relay into the mains behind the wall
where the TV was. Made an exelent TVI/RFI generator, I thought the TV is
going to blow up.


#chuckle#

Back when I was living in a college dorm, the guy in the next room had
pretensions of being a musician - specifically, a drummer. His way of
"practicing" was to turn up his stereo - really loud - so he could
feel the bass, then put on headphones (so that the highs wouldn't hurt
his ears) and then drum along with the music.

Needless to say, this did not make him popular with me or my roommate,
the people on the other side of his room, or the folks downstairs (or,
I suspect, people in the next county). Numerous complaints were filed;
he kept on drumming.

The guy on the other side realized that the drummer's stereo was
plugged into an outlet on one side of their shared wall, and that he
had an outlet on the same circuit. The next time the booming started
up, he plugged his old fluorescent desk light into the outlet, and
then started vibrating his thumb on the pushbutton make/break "start"
switch.

BRRZZBuzzzBZAP.

Stereo goes off suddenly. Two minutes of blessed silence. Stereo
goes back on and the drumming starts again.

BURZZRfffBUZZT.

Lather, rinse, repeat. Eventually, the drummer gives up for the day.

I understand that the drummer never did figure out what was wrong with
the stereo, despite two trips to the repair depot. He left the dorm
at the end of the quarter (I suspect he was "asked" to depart by the
Powers That Be) and we could sleep and study in peace once again.

Hello Henry,

Do you know of other interesting devices or circuits good for misuse?


Six sawed off pieces of the pole of a busted market umbrella allowed me
to move a 1/2ton piece of furniture all by myself.

Oh wait, wrong category....

Regards, Joerg

http://www.analogconsultants.com

On Wed, 21 Dec 2005 01:42:16 GMT, Joerg
wrote:

Hello Henry,

Do you know of other interesting devices or circuits good for misuse?


Six sawed off pieces of the pole of a busted market umbrella allowed me
to move a 1/2ton piece of furniture all by myself.

Oh wait, wrong category....

Regards, Joerg

http://www.analogconsultants.com

I've done that with 1" oak dowel.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

"Winners never quit, quitters never win", Jack Bradley Budnik ~1956

Hello Jim,

I've done that with 1" oak dowel.


But if you bought those I bet my solution was cheaper. About one cent
worth of elctricity to saw it ;-)

Regards, Joerg

http://www.analogconsultants.com

On Wed, 21 Dec 2005 01:57:43 GMT, Joerg
wrote:

Hello Jim,

I've done that with 1" oak dowel.


But if you bought those I bet my solution was cheaper. About one cent
worth of elctricity to saw it ;-)

Regards, Joerg

http://www.analogconsultants.com

I don't know, I save all my scrap ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

"Winners never quit, quitters never win", Jack Bradley Budnik ~1956

Jim Thompson wrote:
On Wed, 21 Dec 2005 01:42:16 GMT, Joerg
wrote:

Hello Henry,

Do you know of other interesting devices or circuits good for misuse?

Six sawed off pieces of the pole of a busted market umbrella allowed me
to move a 1/2ton piece of furniture all by myself.

Oh wait, wrong category....

I've done that with 1" oak dowel.

I've done it with sheer adrenaline (I'm 6'0", 150#) after watching
three big bruisers horse around and get nowhere with an air conditioner
that was IN MY ****ING WAY!!! I stomped up, said "MOVE IT!", grabbed a
corner, shoved hard and walked past. And no, I didn't so much as bend a
fingernail.


Mark L. Fergerson

PS I once used a $150 multimeter as a non-resettable fuse, but I
don't think that's what the OP had in mind...