Talk:Crystal detector

message: January 22, 2018 - "Cat's whisker" refers ONLY to the fine wire or needle that contacts the crystal. The entire device, which this article is about, is a crystal detector. Publications contemporary to common use of this type of detector refer to it as a "crystal detector". For examples see "The Principles Underlying Radio Communication", 2nd Ed., Radio pamphlet no. 40. USA: Prepared by US National Bureau of Standards, United States Army Signal Corps. 1922. pp. 421–425 and F. J. Camm, "Practical Wireless Circuits", 1931, p.5.
LSMFT (talk) 17:43, 22 January 2018 (UTC)
thread_title:  Verifiable Name: Crystal Detector 

message: Suggest we move this to Cat Whisker Detector.
—Preceding unsigned comment added by JA.Davidson (talk • contribs) 
:You mean "Cat-whisker detector"? Dicklyon 05:15, 27 March 2007 (UTC)
thread_title:  Move 

message: Are you sure about the hyphen in cat's-whisker.  I understand the logic, but I don't recall ever seeing a hyphen with a possessive.  Hyphens normally go between compound adjectives to avoid ambiguity.  I guess there could be ambiguity:  the cat's (whisker detector) or the (cat's whisker) detector.  Still, I don't recall ever seeing this construction.  SDC 05:07, 27 March 2007 (UTC)
replies: text: I checked first with Google Book Search.  It is of course common for many books to omit the hyphen in such constructions, since book authors and editors aren't completely literate on the whole, but since a fair number of them did use the hyphen, and since many of the ones that did use the hyphen used quotation marks as in "cat's whister" detector, it seemed clear that there was a consensus that this was not to be written as a detector of cat's whishers as we had before (or was it a detector of whiskers, of by or for the cat?).  I thought the conventional hyphen made more sense than putting quotation marks into the title. Dicklyon 05:13, 27 March 2007 (UTC)
thread_title:  Hyphenation 

message: My purpose in adding the circuit(cct) diagram :file:Detector receiver rus standart.svg was to supplement the technical description in the de-modulation diagram above it. I believe that it makes more sense with a diagram to show what the description says. Another editor removed it, another added it again, and they had an edit summary 'discussion' on the merit of having a cct. diagram. I think a circuit, perhaps with a legend saying what the components are/do, as per the de-mod diagram, has value.  Any comments welcome!  - 220.101 talk\Contribs 07:00, 4 October 2010 (UTC)
replies: text: If you cite a source that mentions crystal detector or cat's whisker and shows such a schematic, then that should be sufficient justification.  I find plenty of books like this one and this one.  The latter illustrates waveforms at different points in the circuit. Dicklyon (talk) 23:04, 4 October 2010 (UTC)
replies: text: It would be best if one could find a schematic of an actual cat's whisker detector set - I don't think the variable capacitor beloved of 21st century textbook authors was a common component of a cat's whisker receiver. --Wtshymanski (talk) 00:54, 5 October 2010 (UTC)
replies: text: The variable capacitor was a mid 20th century innovation.  The radios I built around 1960 used a variable coil, more like this one.  Dicklyon (talk) 03:49, 5 October 2010 (UTC)

text: This one from 1943 (see this search with snippet) says "comprises a fixed inductance, a variable tuning capacitor, an adjustable 'cat- whisker' type of crystal".  Dicklyon (talk) 03:54, 5 October 2010 (UTC)

text: Here's one, but the coil is a transformer.  Dicklyon (talk) 03:56, 5 October 2010 (UTC)
replies: text:  Can't see anything in the snippet view of the first and don't have access to a paper copy.  The transformer in the second is important; from what I've read, most of the capacitance of a typical cat's-whisker receiver is between the antenna and ground, so a variable capacitor is useless in affecting the tuning. When cat's whisker detectors were a viable product, as opposed to the demonstration of principles that they must have been by 1943, one would not have manufactured a crystal set with a variable capacitor. My point ( and I do have one), is that it is misleading to the reader to show a "modern" LC tuned circuit as if this was the circuit actually used when cat's whisker detectors were used in earnest, not as hobby demonstrations of a concept. --Wtshymanski (talk) 13:10, 5 October 2010 (UTC)
replies: text:  And for completeness...I also don't think that schematic drawings have much explanatory power to the general reader not already familiar with the symbols and conventions. If you've been reading Turkish all your adult life, you may not even notice how incongrous it is to have a Turkish paragraph in the middle of an English-language article. --Wtshymanski (talk) 13:25, 5 October 2010 (UTC)
replies: text: One of the things I tossed out as a kid that now I wished I'd saved was a real "cat's whisker" set found in an old house my parents tore down when we bought the place. I don't know if it was a commerical product or very good  home brew (it had no nameplate on it that I recall), but it had a wound coil with a slider for a tuner. The coil former wasn't a piece of an oatmeal box, but was about that size, mounted in some nicely rabbeted wooden end pieces. The galena crystal was in a little metal pot in solder, on a bakelite base with a lever and whisker to probe the surface. All the parts were mounted on a little board with Fahnestock clips (of course we have an article on that) for antenna, ground, and headset connections. For sure it had no variable capacitor but I no longer recall if it had any fixed capacitors. In school shops I built almost a replica with a much smaller coil and a 1N34 diode; as I recall it could only get one station no matter where I put the "tuner", but worked OK for that station. I suspect now that the coil was too small for the antenna I was using, though as a kid I never figured this out. Someone gave me a kit for Christmas which was the same idea; slider on a coil, no capacitors, but a very elaborate plastic case (and a useful high impedance headphone which may still be sitting in a box somewhere in my junk collection). Three crystal sets, one honest-to-Jimbo cat's whisker set, and no tuning capacitors in the lot. --Wtshymanski (talk) 13:50, 5 October 2010 (UTC)

text: (outdent) Problem solved!  Crystal set had the correct diagram. Pictorial, so it doesn't obscure with runic symbols. And authentic, so we don't lie to the reader. --Wtshymanski (talk) 14:04, 5 October 2010 (UTC)
replies: text: You mean this one?: :File:CrystalRadio.jpg I missed out on this discussion, but I did find this excellent PDF of "The 'P.W.' Crystal Experimenters Handbook" which came with the October 1923 issue of "Popular Wireless" . Fig.8 p.22 is a more complicated cct than the one I added, but has a variable cap. and certainly appears to refer to a cats whisker (Galena) as the detector. See also Fig.8 p.20 Variable caps seem to have been around in the early 1920S. See See Page 5 (Fig. E) of Crystal Clear: Vintage American Crystal Sets, Crystal Detectors, and Crystals By Maurice L. Sievers. nb. Variable capacitor has no history information at all. :-( But it appears they were used as early as 1923.  ☢ 220.101 talk\Contribs 08:34, 6 October 2010 (UTC)
replies: text:  The notion of a variable capacitor probably goes back to the Leyden jar when the size of the spark depended on the water level in the jar. --Wtshymanski (talk) 13:16, 6 October 2010 (UTC)

text: Whoops, didnt notice you had already put it in! Layout needs work though!- 220.101 talk\Contribs 08:45, 6 October 2010 (UTC)
thread_title:  Crystal Radio circuit 

message: Does this topic deserve to be separate from the article on Crystal Radio?  John (talk) 21:32, 5 October 2010 (UTC)
replies: text: If Crystal radio wasn't already 75 k (mostly due to a surfeit of low-value citations that could be combined), I'd agree with you.  That article needs to have some of the redundant text about materials moved to this article, at least. --Wtshymanski (talk) 01:21, 6 October 2010 (UTC)
thread_title:  Redundant? 

message: IIRC, the a German worked on microwave detectors, but stopped that research for ethical reasons. British radar developers needed better detectors and somehow stumbled upon the research. Glrx (talk) 17:09, 25 June 2012 (UTC)
thread_title:  German microwave detector 

message: Not even a 100 years ... That word references the centuries B.C. of the Greek and Roman empires and Wikipedia is assumed to be a serious publication ... I would rather tend to use words like "outdated" or "1. generation" or so ... JB. --92.195.103.219 (talk) 03:48, 29 March 2015 (UTC)
thread_title:  Antique ? 

message: Rewrote and expanded "History" section.  I'm not quite done adding sources. --ChetvornoTALK 23:38, 9 August 2018 (UTC)
replies: text: Awesome job, Chet!  Thanks for taking this on. I made some superficial edits; hope that's all OK. Dicklyon (talk) 01:07, 10 August 2018 (UTC)
replies: text:  Thanks for the cleanup! There's a lot of other stuff in there that probably needs work.  I left the citation template markup in expanded format with one field per line, which I know many editors object to; I'll get to that. --ChetvornoTALK 21:45, 24 August 2018 (UTC)
replies: text: I prefer it as you did it.  Dicklyon (talk) 03:08, 25 August 2018 (UTC)
thread_title:  History section 

message: The article says: the wire whisker is the anode, and the crystal is the cathode.  This obviously depends on whether the crystal is n or p type. It might be that some crystals tended one way, so that the rule applied. During WW2, silicon point-contact rectifiers were used with microwave radar at 3GHz and 10GHz. At one point after the war, someone had a Si crystal that was p-type on one end, and n-type on the other. That is, when used as a point contact rectifier, one end conducted one way, and the other end the other way. Understanding this effect led to the beginning of modern semiconductor device physics, including the point contact transistor and pn-junction diode. Gah4 (talk) 06:58, 4 January 2020 (UTC)
thread_title:  ''the wire whisker is the anode, and the crystal is the cathode'' 

message: The section "Cat Whisker" correctly identifies the "buzzer" used to aid in activating the detector, but is incorrectly linked to Buzzer rather than Spark-gap transmitter.  The "buzzer" on early receivers was a spark-gap transmitter in miniature and was called a "buzzer" because it made an audible clicking and buzzing noise because the relay would open/close anywhere from 400 to 2,000 times per second.  With each sparking at the relay contacts, a jolt of radio static was generated.  When the operator could hear the static through the detector then he knew he had corrected .  It is not at all related to the "beeper" or "buzzer" at Buzzer.  This is not original research, please see attached schematic.
When switch S1 closes current flows through coil BZ, which establishes a magnetized field, which opens it's relay contact, which interrupts the circuit and causes a spark across it's terminals.  Because current has stopped, the magnetic field collapses, which returns the relay contacts to their Normally-Closed position, which causes a spark between the contacts and, since current may again flow through coil BZ, the cycle continues.  Gnomenklatura (talk) 02:10, 21 February 2022 (UTC)
thread_title:  Cat Whisker Buzzer 

message: A penny and a safety pin makes a good poor mans Crystal Detector. 2601:408:503:58F0:B586:B9D6:A66F:F354 (talk) 18:21, 23 February 2022 (UTC)
thread_title:  Alternate crystal detector materials. 

message: A tuning system is not required, need only  antenna (50 feet),  ground rod,  high imp earphone, Crystal Detector (penny and safety pin). You'll hear all the stations simultaneously but who cares ?  One will usually overpower the rest  significantly . 2601:408:503:58F0:B586:B9D6:A66F:F354 (talk) 18:33, 23 February 2022 (UTC)
thread_title:  Bare bones.