BLACK HOLE ANTENNA

[mikebg]

Maikl, you know that for me this circuit is incompetent design.
Resistor R2 is top of incompetency. It reduces TX current and draws useless DC current 3mA. This can be easy improved by a capacitor C5 to stop DC. The TX current can be increased by connecting not used gates IC1d, IC1e and IC1f in parallel to IC1a . Capacitor C4 should be electrolytic and circuit will operate with 9V battery. Try this and measure operating point in pin 2. Voltage measured with DC voltmeter should be almost half of battery voltage.

[maikl]

mikebg. So to me, and you agree that Thomas Scarborough "genius" for electronics in general and that he gave a great contribution in the field of metal detectors (and practically and not just theoretical philosophy).A man has invented a simple design CCO that is known to you (no radio, no receiver BFO). TL071 mixer and "crystal Earpiece"replace the entire receiver BFO.

[mikebg]

Sonar target detector

While I've tried to discover myself what amplifies a sound oscillator containing an audio frequency amplifier, microphone and loudspeaker, and whether it can be used as search oscillator for location of different obstacles, it turned out that Rev. Scarborough ahead of me and has already published the circuit diagram of a super simple sonar. Will burst of anger.

[mikebg]

The new edition of electronic Bible in Jan. 2011

"The art of electronics" is sometimes referred to as the "electronics bible", and remains a popular text. Its most
recent (2nd) edition in English was released in 1989 and has been regularly reprinted afterwards: 1990 (twice),
1991, 1993, 1994 (twice), 1995, 1996, 1997, 1998 (twice), 1999, 2001.
I have downloaded for free a scan in *djvu format. The file is 15.2MB zip.
The 2nd edition is in some respects out of date, referencing obsolete electronic components and omitting
technologies developed since it was written. Because of this, the third edition is widely anticipated. In an
undergraduate physics course at Harvard lectured by Paul Horowitz, the January 2010 syllabus mentions that there is
a "new edition coming by Jan. 2011" - 22 years afther last edition. However radio amateurs in Russia insist that the
book has 5 editions in Russian. Surely these are reprints (not edited).
Here is another page with bad circuits.
Search WEB for the old edition. It contains not only bad circuits.

[mikebg]

The category BAD CIRCUITS

To become an amateur a good designer of electronic circuits, he must have read, studied and understood not only
the basic principles of electricity, but few textbooks for electronics. Otherwise, even the Lord does not agree to such
a fate, the incompetent designed circuits will fall into the category "BAD CIRCUITS", which you can see in the
textbook "The Art of Electronics" by Paul Horowitz and Winfield Hill - a popular textbook dealing with analog and
digital electronics. The first edition was in 1980.

[mikebg]

The Rev. and the Bible

Participants in this forum, who can not translate the title of "Rev" in their native language, should know that it stands
for the word "Reverend" - a title used before the name of a minister of the Christian church. In american English
there is a point after abbreviation, ie "Rev.", but there is no point in British English and sometimes is written as
"Revd".
Rev. Thomas Scarborough was the world's most widely published electronics designer for last year. He has well
over 100 designs in print, as well as many in circulation on the Internet. Here is abstract from an interview:
"I began to do electronics in my teens. I had been in ministry for more than ten years before I had my first break as a
writer. Alan Winstanley of Everyday Practical Electronics magazine had been commissioned with reviving a popular
column, and I had many small designs published there. Then Alan suggested that I should try a constructional article
-- a "spread". My first major article was the world's first capacitor-powered flashlight, which was just possible with the
technology of the time."

"I did wonder what God had in mind with my electronics -- it didn't seem to relate to my calling. But it all came
together when I was accepted for a postgraduate degree at Fuller Theological Seminary in Los Angeles. If it hadn't
been for the determination and the skills that I learnt through electronics, and the funding, I doubt that I would have
been able to do it. I think God may often work like that. "
Here is another page from the electronic bible:

[mikebg]

AN ELECTRONIC BIBLE

An of electronics bible is: "The Art of Electronics" by Paul Horowitz and Winfield Hill
In this 30 years old electronic bible there are pages with BAD CIRCUITS.
Note Fig. K in the attached page. Now Maikl knows that here should be connected a resistor. Soon Maikl will know how to calculate the resistance of this resistor, because he will start to read textbooks. But what knows for this circuit an "expert" who was the world's most widely published electronics designer for last year. He has well
over 100 designs in print, as well as many in circulation on the Internet.

[maikl]

I'm not even interested in the development of BFO.TARSOS'm interested to make (your answer will be no good to block diagram). The CCO in the picture is one of many designs (coin from 27mm to 150mm detected). Some CCO with transistors. Design of # 1 is the best (the last in a series) by the author.

[mikebg]

Maikl, the search oscillator is only a part of BFO type metal detector. The circuit in posting #1 is not metal detector, despite the misleding title. Search this forum or WEB for block diagram of BFO metal detector to understand what should contain the whole circuit. In designs made by Rev. Thomas Scarborough, the MW radio operates as BFO (beat frequency oscillator) to produce audible signal. However there are other solutions without BFO despite the name remains (for example with buzzer or LEDs instead BFO). The correct name of these designs should be "frequency shift metal detector".
If you wish to build a complete operating BFO type detector (without MW radio) you can make HOUNDOG or the circuit of Macario (variant with CD4046).
Here is attached another circuit of search oscillator designed by Rev. Thomas Scarborough. This is not bad circuit. Current can flow though TX coil and operating point in pin 5 is allways half of supply voltage because there are resistors inside IC. The circuit is simplified variant of HOUNDOG.

[maikl]

This last is most interesting. Tell me what is the value of R =? and in which BFO to join? Is the picture 2 part of the answer to my question?

[maikl]

Maikl, this is not true! The puzzle says "This is a bad circuit".
Do not mix up an well working principle with an incompetent designed circuit diagram.
BAD CIRCUIT means that because lack of knowledge, its designer did not observe basic rules.
Each oscillator is an amplifier with positive feedback. If it is properly designed, when the feedback is interrupted, the amplifier will have an operating point and will give a great amplification of noise.
The circuit diagram in posting #1 can not do that because of the incompetence of its designer. In fact the circuit oscillates at high frequency only because of stray capacitances and protection diodes in input of opamp. For proper design, TX coil L1 should not be connected to pin 2, but to a point where can flow TX current. Furthermore, pin 3 should receive intermediate voltage 6V via a resistor to establish operating point. Even the 12V supply voltage is choosen incompetent. A properly designed such circuit can operate with smaller voltage.
The principle of operation CCO or IBR (induction balanced regenerator) provides many more opportunities than you indicate in your posting. Leslie Goddard began to use this principle in amateur projects since 60's. I improved her design HOUNDOG achieving results with this principle as a conventional VLF metal detector. I posted on the forum so much information about the benefits of this principle and its use for improving of BFO, that I wonder why you not have read them.

Hi mikebg. I regularly read the new posts on Geotech. I thought you were in "general" against CCO design. You have a lot of interesting ideas:

[mikebg]

Your puzzle says "CCO" = "BAD circuit"

Maikl, this is not true! The puzzle says "This is a bad circuit".
Do not mix up an well working principle with an incompetent designed circuit diagram.
BAD CIRCUIT means that because lack of knowledge, its designer did not observe basic rules.
Each oscillator is an amplifier with positive feedback. If it is properly designed, when the feedback is interrupted, the amplifier will have an operating point and will give a great amplification of noise.
The circuit diagram in posting #1 can not do that because of the incompetence of its designer. In fact the circuit oscillates at high frequency only because of stray capacitances and protection diodes in input of opamp. For proper design, TX coil L1 should not be connected to pin 2, but to a point where can flow TX current. Furthermore, pin 3 should receive intermediate voltage 6V via a resistor to establish operating point. Even the 12V supply voltage is choosen incompetent. A properly designed such circuit can operate with smaller voltage.
The principle of operation CCO or IBR (induction balanced regenerator) provides many more opportunities than you indicate in your posting. Leslie Goddard began to use this principle in amateur projects since 60's. I improved her design HOUNDOG achieving results with this principle as a conventional VLF metal detector. I posted on the forum so much information about the benefits of this principle and its use for improving of BFO, that I wonder why you not have read them.

[maikl]

I have an image for attachment in this thread, but I have not a draft with an explanation of circuits below. This is visual answer to this puzzle. If
someone does not understand the answer made by attached image or have any other questions for "black
hole antenna" of NASA, let ask. I am obliged to seek answers.

Your puzzle says "CCO" = "BAD circuit". That "bad circuit" detects old Victorian penny at a distance of 180mm (coil is a 2 * 120mm), as the average TGSL almost twice higher coil (coil is a 2 * 200mm). Do not insult someone TGSL is a good and stable machine. The CCO is a very unstable (due to the radio), but is given as an experimental idea. TGSL = capacitors-28 pcs., diodes-10 pcs., resistor-54 pcs., transistor-9 pc., integrated circuits-14 pcs. "CCO = integrated circuit-1 pc., capacitor-1 pc."

[mikebg]

The answer

I have an image for attachment in this thread, but I have not a draft with an explanation of circuits below. This is visual answer to this puzzle. If
someone does not understand the answer made by attached image or have any other questions for "black
hole antenna" of NASA, let ask. I am obliged to seek answers.

[mikebg]

SPICE table of NASA

I see an error made by (R)EMI group because the original is not clear. The capacitor 110pF shown above as C6 - COIL (AND TRIM) CAPACITANCE should be noted as C5 according the following SPICE table: