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.... to think it possible!
Now all the CB'ers are doomed to failure! Surely the concept and workings of a phase locked loop are beyond their comprehension! evil-protectionist-chuckle Heee-he-he-he-he! John "Caveat Lector" wrote in message news:Sw7Ge.22116$HV1.13942@fed1read07... A PLL question is on the extra exam See question E7D07 -- CL -- I doubt, therefore I might be ! "John Smith" wrote in message ... How about PLL? John "Caveat Lector" wrote in message news:nH6Ge.22103$HV1.10801@fed1read07... Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? -- CL -- I doubt, therefore I might be ! Someone wrote Draw a Colpitts Oscillator What is a swinging choke |
CL:
If you run into any cb'ers having a problem with that question, it is included on this URL, containing the questions, and the CORRECT answers: http://www.craigr.com/subelement7.htm John "Caveat Lector" wrote in message news:Sw7Ge.22116$HV1.13942@fed1read07... A PLL question is on the extra exam See question E7D07 -- CL -- I doubt, therefore I might be ! "John Smith" wrote in message ... How about PLL? John "Caveat Lector" wrote in message news:nH6Ge.22103$HV1.10801@fed1read07... Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? -- CL -- I doubt, therefore I might be ! Someone wrote Draw a Colpitts Oscillator What is a swinging choke |
Caveat Lector wrote:
A PLL question is on the extra exam See question E7D07 How about "Twiddle factor"? -- 73, Cecil, http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
In article nH6Ge.22103$HV1.10801@fed1read07,
Caveat Lector wrote: Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? I believe that a goodly percentage of fixed-frequency quartz crystal oscillators use a Colpitts configuration in their feedback circuitry. Pierce topologies are likely used, as well. The L in such oscillators is the motional inductance of the crystal, rather than the inductance of a wire-wound inductor, but the principle is still the same. Then why ask these questions on a 2005 Ham test ?? Because the circuits are still relevant, to either modern ham gear, or to the older gear that many hams refurbish and use, or to both. Maybe ask about a VCO or a crowbar circuit ?? VCOs require some form of positive feedback in order to oscillate. This can be in a Colpitts configuration just as well as in any other. Questions about a crowbar would certainly be relevant as well. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
Dave:
I have seen designs used which use a "white noise generator" at their osc. Simply filter the freq you want from it and off you go... John "Dave Platt" wrote in message ... In article nH6Ge.22103$HV1.10801@fed1read07, Caveat Lector wrote: Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? I believe that a goodly percentage of fixed-frequency quartz crystal oscillators use a Colpitts configuration in their feedback circuitry. Pierce topologies are likely used, as well. The L in such oscillators is the motional inductance of the crystal, rather than the inductance of a wire-wound inductor, but the principle is still the same. Then why ask these questions on a 2005 Ham test ?? Because the circuits are still relevant, to either modern ham gear, or to the older gear that many hams refurbish and use, or to both. Maybe ask about a VCO or a crowbar circuit ?? VCOs require some form of positive feedback in order to oscillate. This can be in a Colpitts configuration just as well as in any other. Questions about a crowbar would certainly be relevant as well. -- 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! |
Caveat Lector wrote:
Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? -- CL -- I doubt, therefore I might be ! Someone wrote Draw a Colpitts Oscillator What is a swinging choke The Ameritron ALS-600 solid state amplifier uses a swinging choke in its 50 volt 20 amp power supply. The choke is essentially the regulating element because it swings in and out of core saturation. I understand they now have a SMPS that they will offer with the ALS-600. Maybe they should have some questions about SMPS on the exam. Gary N4AST |
Caveat Lector wrote:
Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? You miss the point! Totally missed the point!! In the 'olden days', the exams were not multiple guess questions; and, they were answered in front of an FCC Engineer. In the olden days one had to commit to some real effort to get a license. In human nature we VALUE that which we work for or invest for. The crime in ham radio today is the 5 hour Saturday morning cram session followed by a VE session; followed by a license; followed by loss of interest in a year or so. I live in a small town with 14 licensed 'hams' with only one active [me] and only one HF station [mine]. IMO there is a significant difference between number of licenses issued or valid and how many hams are on the air. |
.... in the "olden days" it was expected you would be building that equipment
you were being tested on ... .... of course logic and reason now demands the removal of those questions ... John "Ham op" wrote in message ... Caveat Lector wrote: Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? You miss the point! Totally missed the point!! In the 'olden days', the exams were not multiple guess questions; and, they were answered in front of an FCC Engineer. In the olden days one had to commit to some real effort to get a license. In human nature we VALUE that which we work for or invest for. The crime in ham radio today is the 5 hour Saturday morning cram session followed by a VE session; followed by a license; followed by loss of interest in a year or so. I live in a small town with 14 licensed 'hams' with only one active [me] and only one HF station [mine]. IMO there is a significant difference between number of licenses issued or valid and how many hams are on the air. |
Caveat Lector wrote:
Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? Then why ask these questions on a 2005 Ham test ?? Maybe ask about a VCO or a crowbar circuit ?? All of them!!! The reference oscillator in every phase locked loop is generally a Colpitt's oscillator. I suspect that every oscillator in the VCO circuit is also Colpitt's. By simply asking the question you make the point!!! The required level of knowledge for a license today is significantly poorer than 40 or 50 years ago. |
White noise is a critical requirement of the Colpitts/Hartley oscillator
design. Nothing new here! You say you don't know why White noise is required. Better go read Terman or other credible designers. John Smith wrote: Dave: I have seen designs used which use a "white noise generator" at their osc. Simply filter the freq you want from it and off you go... John "Dave Platt" wrote in message ... In article nH6Ge.22103$HV1.10801@fed1read07, Caveat Lector wrote: Just out of curousity -- what modern Ham gear uses a Colpitts oscillator or a swinging choke ?? I believe that a goodly percentage of fixed-frequency quartz crystal oscillators use a Colpitts configuration in their feedback circuitry. Pierce topologies are likely used, as well. The L in such oscillators is the motional inductance of the crystal, rather than the inductance of a wire-wound inductor, but the principle is still the same. Then why ask these questions on a 2005 Ham test ?? Because the circuits are still relevant, to either modern ham gear, or to the older gear that many hams refurbish and use, or to both. Maybe ask about a VCO or a crowbar circuit ?? VCOs require some form of positive feedback in order to oscillate. This can be in a Colpitts configuration just as well as in any other. Questions about a crowbar would certainly be relevant as well. -- 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! |
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