Unusual functions of cheap parts
Henry Kiefer
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
Stefan Heimers
>
> Do you know of other interesting devices or circuits good for misuse?
I never tried it myself, but I heard that some people abused opened memory
chips as cameras, back when CCD camera chips were too expensive for
hobbyists.
http://www.classiccmp.org/pipermail/cctalk/2004-May/042581.html
Henry Kiefer
Yes, I know that. Even EPROM devices can be used. That works principally
with almost any semiconductor, e.g. LED used as photdiode. The efficiency is
poor but the wavelength depend efficiency have interesting properties. There
even exist LED constructed to work reasonable as in AND out device. That is
a benefit if you want duplex fiber line communications....
I mentioned LED:
Here is another one:
If you need a zener diode with very low noise you can use LEDs. That has the
added benefit of having an indicator what is going-on on the board. A common
technique for High-fidelity amps.
- Henry
"Stefan Heimers" <stefan...@heimers.ch> schrieb im Newsbeitrag
news:4385...@news1.ethz.ch...
R.Freitag
[...]
> Do you know of other interesting devices or circuits good for misuse?
Take away the hat of a 2N3055 and use it as a light sensor (sensitive).
Robert
>
> Best regards -
> Henry
--
'Vom Standpunkt eines Beamtenrechtlers aus betrachtet ist der Tod die
schärfstwirkenste aller bekannten, langfristig wirkenden Formen der
vollständigen Dienstunfähigkeit.'
aus: Kommentar zum Beamtenrecht.
Jorgen Lund-Nielsen
Tuner Switching Diodes like the european BA244 (NOT PIN-Diodes!) work
well as medium fast Step Recovery Diodes.
Jorgen
John Larkin
A 1N4007 can also be used as a drift step-recovery diode and as a
plasma avalanche diode. Together, two can generate a kilovolt edge
with a 100 ps risetime.
GAASfets make good fast analog switches; they behave pretty much like
jfets.
Wide-open LDO regulators make nice resettable fuses.
Ferrite beads do all sorts of interesting stuff.
Power mosfets make good heaters, and TO-220 bipolar transistors make
nice temperature sensors.
LVDS line receivers are surprisingly good comparators, and *fast*
I could go on...
John
CA
The LM317 as a radio transmitter
http://web.telia.com/~u85920178/tx/317-tx.htm
John Larkin
I know a guy who uses surface-mount resistors as explosive detonators.
John
Jim Thompson
<otc_f...@gmx.net> wrote:
>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.
[snip]
>
>Best regards -
>Henry
>
That's an interesting use of the 1N4007. I've not tried that, what
kind of off capacitance do you get?
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
John Larkin
Cool. 3T regulators, 317 and LM1117 types, can be neat power amps, for
driving unipolar loads like motors and such. Sort of a follower with a
largish offset.
Hmmm, an LM1117 followed by a monster darlington becomes a
super-follower with roughly zero offset.
John
John Larkin
<jorgen.lu...@xxxxxxxxxxxxdesy.de> wrote:
Tell me about it. I tried some pins to see if they would snap, and
they turn out to have incredibly mushy reverse recovery, Slop Recovery
Diodes.
I'll have to try the varicaps.
John
Phil Hobbs
> A 1N4007 can also be used as a drift step-recovery diode and as a
> plasma avalanche diode. Together, two can generate a kilovolt edge
> with a 100 ps risetime.
Okay, so I'm intrigued already. I have all the hardware available--two
1N4007s and a 3 kV adjustable power supply! How do I build one?
Cheers,
Phil Hobbs
Boris Mohar
Gamma radiation which can be an advantage because it will detect Beta in
presence of Gamma. You have to paint it black. Horrible temperature
sensitivity but you can use another CdS as reference.
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca
void _-void-_ in the obvious place
John Larkin
Google "Grekhov diode." A lot of the papers are for members only, but
this one gives the general idea:
http://www.ece.jhu.edu/~pps/ECE777/ADMAT/CircDev/Pulse-GENERATORS-SHAPERS/sub-nano-pulse1.pdf
Grekhov discovered both the DSRD and the plasma avalanche effects in
cheap power diodes. The core of the DSRD effect is that, if a PIN
diode is forward biased for not too many nanoseconds, the carriers
don't have time to float all around the place so the charge profile is
good for a nice reverse snap. HP did the same thing in their classic
1430 12-GHz sampling head, circa 1965 roughly.
This box used the DSRD effect, in a semiconductor that one would not
expect to be used in an application like this...
http://www.highlandtechnology.com/DSS/T220DS.html
We bias the snap diode +48 volts (yes, forward direction) for about 80
ns before we turn the drive around for the snap. It was originally
designed for use in a LEAP atom probe.
John
Robert Obermayer
2N3055: one-time trigger diode with abt. 160v triggering voltage
[had some ones of unknown state left from a PSU that blew one of 5
transistors, replaced them with MJ15003]
various, sometimes expensive components: firecrackers, smoke bombs,
lamps (most of the time unintended ;) )
old EPROMs: Lamp.Find some pins with low resistance and apply .5-2A.
the IC/transistor that was broken and took you some hours to find the
trouble:
Get 1-5 large caps (like 12 000µF 350V), charge them, and apply the
voltage to the part with a very large relay.
LOUD!
Roy Lewallen
voltage and higher the power dissipation rating, the higher the C. As
someone else mentioned, transistor emitter-base junctions can be used as
either zeners (typical zener voltage around 5 volts) or varicaps.
A zener can be used as a broadband noise source. I've had the best luck
with zeners of 10 - 15 volt breakdown, with around 100 uA current. Some
are noisier than others, and they often have a critical current where
the noise is the greatest.
Tektronix used selected transistors to generate high voltage (~100
volts) fast steps (~100 ps rise time if I recall correctly) by
avalanching the collector. Some fraction of some common transistor types
worked satisfactorily in this application.
1N914 type diodes can be used as step recovery diodes to generate a step
with about a ns risetime -- maybe faster with a chip component and some
care. This could be the basis of a broadband harmonic generator.
Roy Lewallen, W7EL
Jon Yaeger
Wash off the carbon rods. Put each in a wooden clothes pin and connect the
attached ends to the mains voltage (US customers only, please).
Tap the free ends of the rods together. Move them apart as necessary. Very
bright! Much brighter than you are.
Jon
ehsjr
An LED as a shunt regulator. Also, as a varicap.
Ed
Bob Monsen
One of the MIT EE course videos on the web shows a demonstration of AC
across a pickle... it is an interesting effect. Not sure how the pickle
tastes afterward. Cooking hotdogs with AC is similar, but the pickle gives
off a much nicer translucent flickering glow. Very pretty.
---
Regards,
Bob Monsen
The question of the ultimate foundations and the ultimate meaning of
mathematics remains open; we do not know in what direction it will find its
final solution or even whether a final objective answer can be expected at
all. "Mathematizing" may well be a creative activity of man, like language
or music, of primary originality, whose historical decisions defy complete
objective rationalization.
- Hermann Weyl in 1944
Pooh Bear
John Larkin wrote:
> TO-220 bipolar transistors make nice temperature sensors.
I like that trick. Esp the isolated tab type.
Graham
Frithiof Andreas Jensen
"Henry Kiefer" <otc_f...@gmx.net> wrote in message
news:4385b3b1$1$27887$9b4e...@newsread4.arcor-online.net...
> Do you know of other interesting devices or circuits good for misuse?
LED's work both ways, as a light emitter and a photodiode.
The inbuilt colour filter can be used to distinguish between Grass and Not
grass f.ex. by comparing output from a red and a green LED using white light
as illumination.
Back when fiber was ex$$$pensive one often saw clever circuitry using two
transmitters to form a duplex connection over a single fiber.
The USD 10 solar powered garden lamps will, with a little persuation, yield
a nice solar cell well below the price of a similar unit in the shops -
and - two 600 mAh NiMh batteries and a grotty circuit for switching the LED.
John Devereux
> Henry Kiefer wrote:
> > Do you know of other interesting devices or circuits good for misuse?
> > Best regards -
> > Henry
>
> An LED as a shunt regulator. Also, as a varicap.
> Ed
Also a photodetector that is insensitive to long wavelengths (because
of the high bandgap).
--
John Devereux
Ban
At a leading Ultrasonic flaw detector company we used simple low frequency
Motorola sot23 transistors in avalance mode for making a nice pulse
generator for 100MHz probes. These were better than the Zetex avalance
specified transistors.
--
ciao Ban
Apricale, Italy
Jorgen Lund-Nielsen
Hello John,
I wrote: NOT PIN - Diodes - as they wouldn't snap.
i mean Band Switching diodes for TV-Tuners like the BA244 and the BA682.
BA682 Datasheet:
http://www.vishay.com/docs/85530/85530.pdf
- and they snap! Try it!
Jorgen
dj0ud
Jorgen Lund-Nielsen
2N2369 for fast pulses.
2N2222 and even 2N2219 works, but a bit slower and they requiring more
voltage to avalance, but still < 1nS rt
The Zetex are slower but can deliver much more current (up to 60A, ZTX
415 family).
Jorgen
skavanag...@yahoo.ca
there is a well publicized British design for a frequency tripler that
will put out 2 watts at 1.3 GHz and uses five 1N914's in parallel.
I once built an HF transceiver that used CMOS logic chips for all
functions except an audio low noise amp and a voltage regulator...with
further thought those two could likely be done with CMOS logic too.
RST Engineering
large fixed resistor) you can make them into nifty phase shifters.
Jim
Frithiof Andreas Jensen
"Henry Kiefer" <otc_f...@gmx.net> skrev i en meddelelse
news:4385b3b1$1$27887$9b4e...@newsread4.arcor-online.net...
> Do you know of other interesting devices or circuits good for misuse?
Unbuffered logic gates can make a really bad but still useful analogue
amplifier by adding feedback and bias.
John Larkin
<jorgen.lu...@xxxxxxxxxxxxdesy.de> wrote:
I got that!
>i mean Band Switching diodes for TV-Tuners like the BA244 and the BA682.
>
>BA682 Datasheet:
>
>http://www.vishay.com/docs/85530/85530.pdf
>
>- and they snap! Try it!
OK, I'll try some.
Thanks
John
John Larkin
There's also an LM35 in a TO-220 package! Ideal way to monitor a
heatsink.
John
Paul Keinanen
wrote:
>Take apart a couple of D cell carbon-zinc batteries.
>
>Wash off the carbon rods. Put each in a wooden clothes pin and connect the
>attached ends to the mains voltage (US customers only, please).
The problem is that the carbon rod conducts heat quite well, so after
a while, any wooden object will catch fire :-).
>Tap the free ends of the rods together. Move them apart as necessary.
You must have quite slow fuses in 110 V land if you can do a reliable
ignition without blowing the fuse. For 230 V operation, I would
suggest using a current limiting resistor (such as a large heater) or
an inductance (such as fluorescent light ballast) during the ignition.
When there is a solid arc, the current limiter can be shorted out.
Paul
Ron G
Also, for model rockets, burning up an ordinary resistor can be used as a
super-cheap ignitor.
Best---
Ron
John Larkin <jjla...@highNOTlandTHIStechnologyPART.com> wrote in message
news:361co1pavjfi56f0k...@4ax.com...
meow...@care2.com
> A 1N4007 can also be used as a drift step-recovery diode and as a
> plasma avalanche diode. Together, two can generate a kilovolt edge
> with a 100 ps risetime.
>
> GAASfets make good fast analog switches; they behave pretty much like
> jfets.
>
> Wide-open LDO regulators make nice resettable fuses.
>
> Ferrite beads do all sorts of interesting stuff.
>
> Power mosfets make good heaters, and TO-220 bipolar transistors make
> nice temperature sensors.
>
> LVDS line receivers are surprisingly good comparators, and *fast*
>
>
> I could go on...
>
> John
tell us more John
NT
Roy Lewallen
> . . .
> You must have quite slow fuses in 110 V land if you can do a reliable
> ignition without blowing the fuse. For 230 V operation, I would
> suggest using a current limiting resistor (such as a large heater) or
> an inductance (such as fluorescent light ballast) during the ignition.
> When there is a solid arc, the current limiter can be shorted out.
>
Aren't you in danger of damaging your eyes from the UV emitted from the arc?
Roy Lewallen, W7EL
Al
Paul Keinanen <kein...@sci.fi> wrote:
I would put a 100 watt lamp in series thereby limiting the current. I
would shave the ends down to points so they heated up rapidly. I put
them into a hollowed out fire brick and made a cheap furnace. Of course
don't look at it; it's like looking at the sun.
PS: I was 16 at the time ;-)
Robert Obermayer
sorry if you didnt like everything, but sometimes some voilence against
parts that cost you half a day of time and gave you a bad headache while
troubleshooting is necessary...
For more useful things, FETs actually can work as quite useful
one-component HF oscillators if wires and connection points are properly
chosen.With a second transistor one can build a working shortrange AM
transmitter.
A rather useful (works perfectly for SMPS uses) AC current probe for a
scope can be made by using a small UI cored RFI filter coil from a
monitor, connecting its windings in series and terminating with a 1ohm
resistor, to which a coax cable with BNC connector is soldered to.
The wire you want to measure the current in simply is fed trough the
core one time.
This only gives quantitative measurements unless calibrated but can be
very useful if you cant afford a real current probe.
The known resonant royer circiut used for CCFL inverters can be used for
larger inverters if appropriate parts are chosen, and can produce some
high frequency/high voltage with a transformer from a old TV (with no
internal rectifier).
This has its uses, besides connecting it to a old light bulb that works
as plasma globe or connecting both outputs to a large neon bulb
[Bienenkorbglimmlampe], which simply looks very nice but also produces
lots of RFI, so dont run it for too long.
FET gate drivers make nice TTL output stages for function generators, as
these can drive rather high currents and are fairly robust.
If a slowly, steadily changing linear voltage is necessary (for ex.
confirming the linearity of something) a 10turn precicion pot copuled
with a slow syncronous motor (a old microwave oven has a nice 2.5u/min
one) by some tape (so it slips/breaks when the pot is at its endpoint)
works nicely.
Si Ballenger
The current limiter I saw used a glass pie pan with pieces copper
metal on each side with salty water as the electrolyte. It would
start to steam some when in operation. The furnace was a small
clay flower pot with holes in each side with the carbon rods
sticking inside until they touched.
Phil Hobbs
>>I would put a 100 watt lamp in series thereby limiting the current. I
>>would shave the ends down to points so they heated up rapidly. I put
>>them into a hollowed out fire brick and made a cheap furnace. Of course
>>don't look at it; it's like looking at the sun.
>
>
> The current limiter I saw used a glass pie pan with pieces copper
> metal on each side with salty water as the electrolyte. It would
> start to steam some when in operation. The furnace was a small
> clay flower pot with holes in each side with the carbon rods
> sticking inside until they touched.
>
As a boy, I used an electric teakettle as a ballast for a two-D-cell carbon
arc lamp--worked great.
Cheers,
Phil Hobbs
Ralph Barone
Al <no....@wanted.com> wrote:
I used a 0.5 or 0.7 mm pencil lead gently torqued down across the
terminals of a regulated DC power supply. Set the current limit very
low, crank the voltage up all the way and increase the current limit
until the center of the lead starts glowing red. Due to the heatsinking
effect of the binding posts, the lead will always heat up the most in
the center, then the carbon will start to evaporate and the remaining
lead will gradually neck down in the center until it is glowing white
hot. As soon as the lead breaks in the middle, you convert from
incandescent to carbon arc lamp, which usually surprises everybody
watching. The arc is good for about 5 seconds until the voltage drop
across the arc exceeds the capability of the power supply.
**THE-RFI-EMI-GUY**
for a crystal oven.
Joe Leikhim K4SAT
"The RFI-EMI-GUY"
"Follow The Money"
Pooh Bear wrote:
--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"
"Follow The Money"
Paul Keinanen
wrote:
Certainly.
I used arc welding glasses when conducing these experiments.
Some trivia:
In the silent film era, actors had eye problems due to the UV
radiation from arc studio lamps.
Most of the usable illumination from the arc lights is actually from
the glowing carbon electrodes.
"Automatic arc lights" used a solenoid in series with the arc to keep
the distance constant between the poles regardless of carbon electrode
burnout. I assume that if this is to be used with a AC arc light, both
the moving coil as well as the static coil should carry the arc
current.
Paul OH3LWR
Murray
E.G the CMOS 4007. See the old handbooks for a '100dB
amplifier' based on a RCA chip - there was a wiring
error in that old description - IIRC it was 3800? -
whatever, the 4007 is the same chip.
Murray vk4aok
Paul Keinanen
>Frithiof Andreas Jensen wrote:
>E.G the CMOS 4007. See the old handbooks for a '100dB
>amplifier' based on a RCA chip - there was a wiring
>error in that old description - IIRC it was 3800? -
>whatever, the 4007 is the same chip.
The Motorola McMOS handbook (2nd edition 1974) warns about this usage
by pointing out that by cascading three such AC coupled stages, the
last stage will be saturated by the noise from the first stage.
Paul OH3LWR
wa2mze(spamless)
> Henry Kiefer wrote:
>
>
>>Do you know of other interesting devices or circuits good for misuse?
>
>
> chips as cameras, back when CCD camera chips were too expensive for
> hobbyists.
>
> http://www.classiccmp.org/pipermail/cctalk/2004-May/042581.html
>
> http://groups.google.com/group/comp.robotics.misc/browse_thread/thread/652cc4b0e1ccee57/f84b0f2d5c0b6da7?lnk=st&q=opened+RAM+chips+used+as+camera&rnum=6#f84b0f2d5c0b6da7
>
Yes, a co-worker at a former job and myself peeled the top off a 22pin dram chip
(we went through several brands to find one that had the memory array in one
large area rather then 4 smaller areas) and then replaced the top with a microscope
slide cover. By re-reading the array and timing how long it took for the
ones to decay to zeros (or visa versa) we were able to get about 4 levels of
gray scale. A tiny lens from a broken camera view finder was mounted above the
chip and I rigged up a way to move the chip back and forth to focus. Our first
'subject' was a 60w light bulb. We were using an AppleII (gives you an idea
of how long ago this was) to do the image processing. We both went 'crazy'
when we saw the '60 Watt' from the top of the bulb on the screen!
The resolution of our camera wasn't even as good as early SSTV (maybe 64 x 64
pixels) but it did work.
wa2mze(spamless)
> 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.
>
>
> Henry
>
>
Take one P channel Jfet and one N channel Jfet and connect them
in series so the two sources are together, connect the gate of
each transistor to the other one's drain. This is known as a lambda
connection, and if you plot the voltage vs current from drain to drain
you will see a negative resistance region, usually around 3v
(depending on the transistors). The circuit will work as a tunnel
diode oscillator up to 100-200mhz.
wa2mze(spamless)
> ignition without blowing the fuse. For 230 V operation, I would
> suggest using a current limiting resistor (such as a large heater) or
> an inductance (such as fluorescent light ballast) during the ignition.
> When there is a solid arc, the current limiter can be shorted out.
>
> Paul
>
Did you know that a carbon arc acts as a negative resistance? Run the
arc on DC and put an LC tuned circuit in series with the arc (coil of
heavy copper tubing) and you have a powerful oscillator.
Rick
"Si Ballenger" <shb*NO*SPAM*@comporium.net> wrote in message
news:4387be6d....@news.comporium.net...
Exactly-when I was a kid we made them like this all the time. As I
recall, it came from "700 scientific experiments, with
illustrations"...
>
Jim Thompson
I've used a light bulb in series with a rectifier to charge a car
battery (just make sure that line ground goes to chassis ground ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Matthias Weingart
news:8764qh8...@cordelia.devereux.me.uk:
> ehsjr <eh...@bellatlantic.net> writes:
>> Henry Kiefer wrote:
>> > Do you know of other interesting devices or circuits good for
>> > misuse? Best regards -
>> > Henry
>>
>> An LED as a shunt regulator. Also, as a varicap.
>> Ed
>
> Also a photodetector that is insensitive to long wavelengths
> (because of the high bandgap).
To save power, use the LEDs of a backlight to measure the ambient light
to decide to switch the backlight on or not.
M.
--
Bitte auf mwn...@pentax.boerde.de antworten.
John Larkin
wrote:
We worked with a company that was developing an xray imager, and was
buying very expensive electrically conductive glass (gigohms per
square sort of range.) They discovered that certain welding glass was
identical and about 1/20 the price.
John
Oliver Betz
[...]
>If you need a zener diode with very low noise you can use LEDs. That has the
you mean forward biased? Reverse breakdown of most cheap LEDs is IIRC
around 100V.
Oliver
--
Oliver Betz, Muenchen (oliverbetz.de)
Winfried Salomon
Jorgen Lund-Nielsen wrote:
[.....]
> 2N2369 for fast pulses.
btw, do you know a standard complementary pnp-transistor for the 2N2369,
such like 2N3905 but with higher ft and less feedback capacitance? It
seems that the manufactorers have almost no data on their internet pages.
mfg. Winfried
John - KD5YI
> On Fri, 25 Nov 2005 22:13:38 -0500, Phil Hobbs
> <pcdhSpamM...@us.ibm.com> wrote:
>
>
>>Si Ballenger wrote:
>>
>>
>>>>I would put a 100 watt lamp in series thereby limiting the current. I
>>>>would shave the ends down to points so they heated up rapidly. I put
>>>>them into a hollowed out fire brick and made a cheap furnace. Of course
>>>>don't look at it; it's like looking at the sun.
>>>
>>>
>>>The current limiter I saw used a glass pie pan with pieces copper
>>>metal on each side with salty water as the electrolyte. It would
>>>start to steam some when in operation. The furnace was a small
>>>clay flower pot with holes in each side with the carbon rods
>>>sticking inside until they touched.
>>>
>>
>>As a boy, I used an electric teakettle as a ballast for a two-D-cell carbon
>>arc lamp--worked great.
>>
>>Cheers,
>>
>>Phil Hobbs
>
>
> I've used a light bulb in series with a rectifier to charge a car
> battery (just make sure that line ground goes to chassis ground ;-)
>
> ...Jim Thompson
Going the other direction, I used the elements from a toaster as a load to
discharge wet-cell lead-acid batteries. It was a discharge/charge cycling test.
John
Jim Thompson
A 2N2369 is a gold-doped NPN, gold-doped to kill storage time and
improve recovery from saturation. I don't recall any PNP device with
gold-doping... or the equivalent.
Henry Kiefer
room felt that the tv was going crazy. The pins had long wires...
- Henry
<skavanag...@yahoo.ca> schrieb im Newsbeitrag
news:1132928901.2...@g43g2000cwa.googlegroups.com...
> As an addition to the various mentions of common diodes as varactors
> there is a well publicized British design for a frequency tripler that
> will put out 2 watts at 1.3 GHz and uses five 1N914's in parallel.
>
> I once built an HF transceiver that used CMOS logic chips for all
> functions except an audio low noise amp and a voltage regulator...with
> further thought those two could likely be done with CMOS logic too.
>
Henry Kiefer
Don't forget the temperature characteristics!
- Henry
"Murray" <m...@erewhon.net> schrieb im Newsbeitrag
news:43884488$0$12455$5a62...@per-qv1-newsreader-01.iinet.net.au...
Henry Kiefer
Is the oscillator useful at 150MegHz? Modulable? Maybe I can make
transmitter...
Tell us more, please.
cu -
Henry
"wa2mze(spamless)" <"wa2mze(spamless)"@bellsouth.net> schrieb im Newsbeitrag
news:tT_hf.27576$s92....@bignews6.bellsouth.net...
Henry Kiefer
control. Some high-fidelity enthusiasts use this in good audio amplifiers.
- Henry
"ehsjr" <eh...@bellatlantic.net> schrieb im Newsbeitrag
news:R3thf.9922$BU2.983@trndny01...
> Henry Kiefer wrote:
> > 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
> >
> >
>
Henry Kiefer
operation.
- Henry
"Frithiof Andreas Jensen" <frithiof.jensen@die_spammer_die.ericsson.com>
schrieb im Newsbeitrag news:dm6msq$bvk$1...@news.al.sw.ericsson.se...
>
> "Henry Kiefer" <otc_f...@gmx.net> wrote in message
> news:4385b3b1$1$27887$9b4e...@newsread4.arcor-online.net...
>
> > Do you know of other interesting devices or circuits good for misuse?
>
> LED's work both ways, as a light emitter and a photodiode.
>
> The inbuilt colour filter can be used to distinguish between Grass and Not
> grass f.ex. by comparing output from a red and a green LED using white
light
> as illumination.
>
> Back when fiber was ex$$$pensive one often saw clever circuitry using two
> transmitters to form a duplex connection over a single fiber.
>
> The USD 10 solar powered garden lamps will, with a little persuation,
yield
> a nice solar cell well below the price of a similar unit in the shops -
> and - two 600 mAh NiMh batteries and a grotty circuit for switching the
LED.
>
>
John Larkin
<frithiof.jensen@die_spammer_die.ericsson.com> wrote:
>
>"Henry Kiefer" <otc_f...@gmx.net> wrote in message
>news:4385b3b1$1$27887$9b4e...@newsread4.arcor-online.net...
>
>> Do you know of other interesting devices or circuits good for misuse?
>
>LED's work both ways, as a light emitter and a photodiode.
>
And optocouplers can do interesting things:
Very simple high-voltage opamp, up to 400 volts p-p.
Isolated totem-pole driver, from a few volts up to 400.
Current limiter.
Low-leakage diode, sort of like an LED painted black.
John
Ken Smith
Henry Kiefer <otc_f...@gmx.net> wrote:
>Don't forget the LED as an low-noise zener diode with integrated function
>control. Some high-fidelity enthusiasts use this in good audio amplifiers.
It also works for this:
Vcc
!/c
--/\/\/\---+------!
! !\e
V !
--- ----/\/\/--+--- too load
! !
--------------------
You get a current limit and an indicator light.
--
--
kens...@rahul.net forging knowledge
Henry Kiefer
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
Henry Kiefer
- Henry
"Oliver Betz" <OB...@despammed.com> schrieb im Newsbeitrag
news:438da5d3....@z1.oliverbetz.de...
Henry Kiefer
- Henry
"John Larkin" <jjla...@highNOTlandTHIStechnologyPART.com> schrieb im
Newsbeitrag news:nasho1do5hpdjfa6i...@4ax.com...
John Larkin
I posted some opamp schematics to abse a while back. I guess I could
do it again if they're no longer available.
The others chould be fairly obvious.
John
Martin
> As an addition to the various mentions of common diodes as varactors
> there is a well publicized British design for a frequency tripler that
> will put out 2 watts at 1.3 GHz and uses five 1N914's in parallel.
>
> I once built an HF transceiver that used CMOS logic chips for all
> functions except an audio low noise amp and a voltage regulator...with
> further thought those two could likely be done with CMOS logic too.
>
At least the audio amp, this is nice to build with some Inverters (4069)
with resistive Feedback.
--
Martin
Boris Mohar
A latch.
--
Boris Mohar
Martin
<pcdhSpamM...@us.ibm.com>:
> Si Ballenger wrote:
>
>>> I would put a 100 watt lamp in series thereby limiting the current. I
>>> would shave the ends down to points so they heated up rapidly. I put
>>> them into a hollowed out fire brick and made a cheap furnace. Of
>>> course don't look at it; it's like looking at the sun.
>> The current limiter I saw used a glass pie pan with pieces copper
>> metal on each side with salty water as the electrolyte. It would
>> start to steam some when in operation. The furnace was a small
>> clay flower pot with holes in each side with the carbon rods
>> sticking inside until they touched.
>>
>
> As a boy, I used an electric teakettle as a ballast for a two-D-cell
> carbon arc lamp--worked great.
>
An electric arc with just 3V from two D-cells? I thought the arc needs at
lesat 20V burning voltage.
--
Martin
Phil Hobbs
It ran off 120 V. Parse the sentence as "two D-cell-carbon arc lamp." An
earlier poster talked about building AC-powered arc lamps using the carbon
rods from dry cells.
Cheers,
Phil Hobbs
John Larkin
Right, if CTR > 1.
John
Martin
<mwn...@pentax.boerde.de>:
But how to decide to switch it off? I think there you have to sample -
switch of for a short time and test. This could give a flickering
backlight.
--
Martin
David DiGiacomo
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.
Matthias Weingart
news:ops0vsn1...@news.gmx.at:
>> To save power, use the LEDs of a backlight to measure the ambient
>> light to decide to switch the backlight on or not.
>>
> But how to decide to switch it off? I think there you have to
> sample - switch of for a short time and test. This could give a
> flickering backlight.
Ok, you found the skeleton in the closet. :-) You can not use
this method to switch it off - but it is not required in most cases.
Think of a cell phone - the backlight goes on every time you press a
key, and it is going off after 10 seconds.
Martin
<mwn...@pentax.boerde.de>:
> Martin <marti...@gmx.at> wrote in
OK, so you can decide to not switch it on and save some mAs.
--
Martin
skavanag...@yahoo.ca
Martin wrote:
> > I once built an HF transceiver that used CMOS logic chips for all
> > functions except an audio low noise amp and a voltage regulator...with
> > further thought those two could likely be done with CMOS logic too.
> >
> At least the audio amp, this is nice to build with some Inverters (4069)
> with resistive Feedback.
Most of the audio section was done that way. But the product detector
had low impedance output and the CMOS amp was too noisy at 50 ohms. A
transformer might have done the job but a common-base amp seemed more
practical and less prone to picking up hum.
Steve
Martin
<pcdhSpamM...@us.ibm.com>:
OK :-) I liked to do that myself, but not from our 230V mains power, but
with a transformer, 22V, and 30A short circuit.
--
Martin
Winfried Salomon
Jim Thompson wrote:
[...]
>>btw, do you know a standard complementary pnp-transistor for the 2N2369,
>>such like 2N3905 but with higher ft and less feedback capacitance? It
>>seems that the manufactorers have almost no data on their internet pages.
[...]
>
>
> A 2N2369 is a gold-doped NPN, gold-doped to kill storage time and
> improve recovery from saturation. I don't recall any PNP device with
> gold-doping... or the equivalent.
thank you, then I suppose the 2N3905 oder 2N2905 are fitting for a large
signal amplifier.
mfg. Winfried
Rich the Newsgroup Wacko
> Take apart a couple of D cell carbon-zinc batteries.
>
> Wash off the carbon rods. Put each in a wooden clothes pin and connect the
> attached ends to the mains voltage (US customers only, please).
>
> Tap the free ends of the rods together. Move them apart as necessary. Very
> bright! Much brighter than you are.
I put mine in series with Mom's iron, but the thermostat kept turning
it off.
--
Cheers!
Rich
------
"I don't drink water; fish fuck in it."
-- W.C. Fields
Rich Grise
> On Thu, 24 Nov 2005 18:49:24 -0500, Jon Yaeger wrote:
>
>> Take apart a couple of D cell carbon-zinc batteries.
>>
>> Wash off the carbon rods. Put each in a wooden clothes pin and connect the
>> attached ends to the mains voltage (US customers only, please).
>>
>> Tap the free ends of the rods together. Move them apart as necessary. Very
>> bright! Much brighter than you are.
>
> One of the MIT EE course videos on the web shows a demonstration of AC
> across a pickle... it is an interesting effect. Not sure how the pickle
> tastes afterward. Cooking hotdogs with AC is similar, but the pickle gives
> off a much nicer translucent flickering glow. Very pretty.
>
But who wants a cooked pickle? ;-)
Thanks,
Rich
John Perry
> ...
>
> But who wants a cooked pickle? ;-)
>
My ethnic Russian daughter-in-law, just arrived from Tatarstan, made a
Russian soup, into which she chopped several dill pickles.
Wonderful stuff!
John Perry
Spehro Pefhany
Recipe? ;-) It's getting into soup/curry/stew weather here in the
frozen* north.
* Actually just cold nasty rain, but there was some snow earlier this
week.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
lang...@ieee.org
Jim Thompson skrev:
> On Fri, 25 Nov 2005 22:13:38 -0500, Phil Hobbs
> <pcdhSpamM...@us.ibm.com> wrote:
>
> >Si Ballenger wrote:
> >
> >>>I would put a 100 watt lamp in series thereby limiting the current. I
> >>>would shave the ends down to points so they heated up rapidly. I put
> >>>them into a hollowed out fire brick and made a cheap furnace. Of course
> >>>don't look at it; it's like looking at the sun.
> >>
> >>
> >> The current limiter I saw used a glass pie pan with pieces copper
> >> metal on each side with salty water as the electrolyte. It would
> >> start to steam some when in operation. The furnace was a small
> >> clay flower pot with holes in each side with the carbon rods
> >> sticking inside until they touched.
> >>
> >
> >As a boy, I used an electric teakettle as a ballast for a two-D-cell carbon
> >arc lamp--worked great.
> >
> >Cheers,
> >
> >Phil Hobbs
>
> I've used a light bulb in series with a rectifier to charge a car
> battery (just make sure that line ground goes to chassis ground ;-)
>
I've seen several speakers where there was a light bulb, in series with
the tweeter, as a power limiter
-Lasse
Jim Thompson
<spef...@interlogDOTyou.knowwhat> wrote:
>On Mon, 28 Nov 2005 18:24:52 -0500, the renowned John Perry
><j...@no.spam> wrote:
>
>>Rich Grise wrote:
>>> ...
>>>
>>> But who wants a cooked pickle? ;-)
>>>
>>
>>My ethnic Russian daughter-in-law, just arrived from Tatarstan, made a
>>Russian soup, into which she chopped several dill pickles.
>>
>>Wonderful stuff!
>>
>>John Perry
>
>Recipe? ;-) It's getting into soup/curry/stew weather here in the
>frozen* north.
>
>* Actually just cold nasty rain, but there was some snow earlier this
>week.
>
>
>Best regards,
>Spehro Pefhany
Expect more nasty weather... it's heading your way. Here on Saturday
night... very windy, Sunday night plunged to about 25°F.
Got in the wife's car on Saturday and backed out into the street, and
commented, "Why is the AC blowing warm air?"
Wife replies, " I don't know, it did that for awhile yesterday, too."
I pushed the Ambient button on the dash... it was 65°F outside...
winter has arrived in Arizona ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Spehro Pefhany
Ha. Well, there's a nice dry maple log in the fireplace, an ice-cold
Sapporo in one of my Royal Selangor double-wall frozen pewter
tankards, my VHDL code is working with minimal tweaking and all is
right with the world. ;-)
Jim Thompson
<spef...@interlogDOTyou.knowwhat> wrote:
We burned a log in the fireplace last night also. It was sufficient
to keep the inside temperature above 68°F. Don't know yet if I'll
need to turn on the heat this year or not.
Martin
<g...@example.net>:
> On Thu, 24 Nov 2005 18:49:24 -0500, Jon Yaeger wrote:
>
>> Take apart a couple of D cell carbon-zinc batteries.
>>
>> Wash off the carbon rods. Put each in a wooden clothes pin and connect
>> the
>> attached ends to the mains voltage (US customers only, please).
>>
>> Tap the free ends of the rods together. Move them apart as necessary.
>> Very
>> bright! Much brighter than you are.
>
> I put mine in series with Mom's iron, but the thermostat kept turning
> it off.
One time I used an old Iron as a dummy-load for a 230V/1kW TRIAC power
control circuit (we had it in the lab for improvised BGA soldering). To
"satisfy" the thermostat I used a 30cm room fan.
--
Martin
Jon Yaeger
> I've seen several speakers where there was a light bulb, in series with
> the tweeter, as a power limiter
>
> -Lasse
I once owned a Knight transistorized amp that used incandescent bulbs in the
output stage to limit current. When you had some brighteness, you had a
problem.
I remember that it was the very worst-sounding amplifier that I ever owned.
jon
Rich Grise, Plainclothes Hippie
> Rich Grise wrote:
>>
>> But who wants a cooked pickle? ;-)
>
> My ethnic Russian daughter-in-law, just arrived from Tatarstan, made a
> Russian soup, into which she chopped several dill pickles.
>
> Wonderful stuff!
You must have to cook the bejabbers out of them - I chopped up a dill
pickle once into a stew I was concocting from leftovers ane expired stuff
in the pantry, and it was kind unnerving every time I bit into a pickle
chunk. Or maybe I didn't chop them finely enough. (more like I "cubed"
them.) My Mom [RIP] used to put weiners and sweet pickles through the meat
grinder. Simultaneously. I refused to even taste the stuff. ;-)
Thanks!
Rich
Rich Grise, Plainclothes Hippie
> On Mon, 28 Nov 2005 18:24:52 -0500, the renowned John Perry
> <j...@no.spam> wrote:
>
>>Rich Grise wrote:
>>> ...
>>>
>>> But who wants a cooked pickle? ;-)
>>>
>>
>>My ethnic Russian daughter-in-law, just arrived from Tatarstan, made a
>>Russian soup, into which she chopped several dill pickles.
>>
>>Wonderful stuff!
>>
>>John Perry
>
> Recipe? ;-) It's getting into soup/curry/stew weather here in the
> frozen* north.
>
> * Actually just cold nasty rain, but there was some snow earlier this
> week.
Recipe? For _STEW_??!!?????
You brown some meat, throw it into a pot with some veggies, add enough
water so it doesn't boil dry, cover it, and simmer it until it starts to
smell like food. ;-)
(Then again, I used to watch Mom cook. ;-) )
Cheers!
Rich
Tim Williams
news:BFB132A4.43C18%jon...@bellsouth.net...
> I once owned a Knight transistorized amp that used incandescent bulbs
> in the output stage to limit current. When you had some brighteness,
> you had a problem.
>
> I remember that it was the very worst-sounding amplifier that I ever
> owned.
Heh heh. I have a Knight kit-built amp that glows too, but that's a bias
problem in the tube output...
...No, I don't use it regularly...
Tim
--
Deep Fryer: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms
Spehro Pefhany
I think I remember something like that, maybe with ground beef.
Here's a recipe for 'Solianka' soup with dill pickle, pickle juice and
a bunch of hearty stuff. They might make it differently in Tartarstan
though (home of Tartar sauce, I presume):
http://soup.allrecipes.com/AZ/SoliankaRussianBeefSoup.asp
From other recipes for Solyanka (or however it's spelt/spelled) the
common factors are beef broth, pickles, olives, capers, onions, garlic
and some kind of meat-- other winter veggies are fair game. And a
dollop of sour cream.
John Perry
> On Tue, 29 Nov 2005 03:23:06 GMT, the renowned "Rich Grise,
> Plainclothes Hippie" <f...@example.com> wrote:
>
>
>>On Mon, 28 Nov 2005 18:24:52 -0500, John Perry wrote:
>>
>>>Rich Grise wrote:
>>>
>>>>But who wants a cooked pickle? ;-)
>>>
>>>My ethnic Russian daughter-in-law, just arrived from Tatarstan, made a
>>>Russian soup, into which she chopped several dill pickles.
>>>
>>>Wonderful stuff!
>>
>>You must have to cook the bejabbers out of them - I chopped up a dill
>>pickle once into a stew I was concocting from leftovers ane expired stuff
> From other recipes for Solyanka (or however it's spelt/spelled) the
> common factors are beef broth, pickles, olives, capers, onions, garlic
> and some kind of meat-- other winter veggies are fair game. And a
> dollop of sour cream.
>
Well, Galya's was all vegetable except for a cube or two of bouillon (I
don't know what kind). She had chopped the vegetables so finely that I
didn't notice the pickles until she showed me the jar she took them from
(I couldn't understand her description of "spiced cucumbers" :-).
I don't know how she made it, since I had put her son, my step-grandson,
to work with me raking a ton or so of oak leaves from my six 100+-foot
trees.
Even a lovely season like autumn has its price.
John Perry
Highland Ham
> winter has arrived in Arizona ;-)
Winter ? That's a comfortable Summer temp. here in northern Scotland.
Frank GM0CSZ / KN6WH
Jorgen Lund-Nielsen
Winfried Salomon wrote:
> Hello Jorgen,
>
> Jorgen Lund-Nielsen wrote:
>
> [.....]
>
>> 2N2369 for fast pulses.
>
>
> btw, do you know a standard complementary pnp-transistor for the 2N2369,
> such like 2N3905 but with higher ft and less feedback capacitance? It
> seems that the manufactorers have almost no data on their internet pages.
>
> mfg. Winfried
Maybe 2N4261 ? Have not looked into the datasheet, but as i remember,
i have seen them sometimes in complementary with the 2N2369
Jorgen
Henning Paul
> I think I remember something like that, maybe with ground beef.
You mean Labskaus?
http://en.wikipedia.org/wiki/Labskaus
Here in Bremen/Germany we usually leave away the fish and use just Corned
Beef (the brazilian Corned Beef is just fine). And sometimes, you find
diced pickles in it. Tastes even better, then.
regards
Henning
--
henning paul home: http://www.geocities.com/hennichodernich
PM: henni...@gmx.de , ICQ: 111044613
Spehro Pefhany
I know how to make stew, without a recipe, but it wouldn't taste like
Russian stuff with capers, olives and pickles. I guess you have to
make it only from stuff that would be available in the Russian
countryside in February, and spice it up with the appropriate
crunchy/salty bits.
>(Then again, I used to watch Mom cook. ;-) )
>
>Cheers!
>Rich
Spehro Pefhany
<henni...@gmx.de> wrote:
>Spehro Pefhany schrieb:
>
>> I think I remember something like that, maybe with ground beef.
>
>You mean Labskaus?
>http://en.wikipedia.org/wiki/Labskaus
Noo.... I think I would have remembered something which looked like
*that*.
>Here in Bremen/Germany we usually leave away the fish and use just Corned
>Beef (the brazilian Corned Beef is just fine). And sometimes, you find
>diced pickles in it. Tastes even better, then.
>
>regards
>Henning
Sounds basically like corned beef hash with sides of fried egg, pickle
and perhaps rollmop herring. Though more gooey with mashed potatoes
used rather than chopped.
Oliver Betz
>You mean Labskaus?
>http://en.wikipedia.org/wiki/Labskaus
Uh, real Labskaus doesn't contain fish. And the picture is
unappetizing.
Oliver
--
Oliver Betz, Muenchen (oliverbetz.de)