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Oscillator design 0-12 MHz
Hello
If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom |
On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote:
Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. 73 de Leigh W3NLB |
Leigh W3NLB writes:
On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. Are you kidding? almost all my attempted oscillators run at 0Mhz.. |
In message , Leigh W3NLB
writes On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. I've seen them in little boxes in Woolworths. Mike -- M.J.Powell |
"Leigh W3NLB" wrote in message
... On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. 73 de Leigh W3NLB ------------------------------------------------ Nah for 0 MHz -- have a switch labeled 0 MHz -- fed by a battery. Its the 0.00000000000000000000000000000001 Hertz that will be a problem All in good fun. Seriously you need to decide on accuracy and stability first which will dictate whether you will be building an analog, or synthesized unit. For an analog homebrew project -- see URL: http://www.vintage-radio.com/project...enerator.shtml Covers 150kHz to 12 MHz. For the lower frequencies -- get a hold of some of the later solid state Heathkit Audio generator manuals. Or from scratch -- consider the following books: http://www.sss-mag.com/cosc.html#books |
Leigh W3NLB ) writes:
On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. 73 de Leigh W3NLB The workaround is to have a variable oscillator beating against a fixed oscillator. So you have your variable oscillator going from 30 to 42MHz (I just picked those out of my hat), a fixed oscillator running at 30 MHz, and a mixer fed with both oscillators. The output of the mixer will be 0 to 12MHz (plus some other things). Michael VE2BVW |
I need to get one of the MAX038EVKIT oscillator evaluation kits shown at the website below but can't check the price nor order it without being a logged-in member, and don't believe that would work out for a one piece hanm radio use purchase. Where/how can I just order a single unit? Dick Maxim has an enlightened purchasing policy and will sell at a small premium, 1 or 2 of anything in their product line direct. W4ZCB |
"Tom" wrote in message ... Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. A DDS chip like the Analog Devices AD9850 will give you something close to that. It won't quite go down to 0 MHz, though. You could just switch it off, of course. Leon -- Leon Heller, G1HSM http://www.geocities.com/leon_heller |
W7TI ) writes:
On Fri, 18 Jul 2003 14:05:06 +0200, "Tom" wrote: If you read my original post again or at least the topic, it says 0-12 (not 0, 12) MHz. And that would mean something in the range between 0 and 12. I don't remember when and WHERE i said that i need 0 MHz oscilator. The only one who talks about 0 MHz osc is you. __________________________________________________ _______ Perhaps English is a second language for you, but when you say 0-12 that will be taken to mean those two frequencies and everything in between. -- Bill, W7TI And of course, even if such a full range oscillator was not intended by the original poster, I'd say there often is a big difference between oscillators in the KHz range and those in the MHz range. Obviously, the concept of an oscillator doesn't change, but the specific design does. You can use resistors and capacitors to set the frequency down near the audio range, and do your best to avoid coils down there due to their size, while once you get into radio frequencies, one tends to use coils for the frequency control element. Time after time, I see people asking questions about oscillators, and often they are coming to radio frequencies from an audio background. So they think in terms of just scaling some favorite audio oscillator up to radio frequencies, when a simpler solution would be to use an LC oscillator. Somewhere in this thread, the 8038's more recent spawn was mentioned. Obviously, it will work over that full range, but I'm suspicious about how good it will be at radio frequencies, as I would about any RC oscillator. It seems a stretch to expect it to work as well at 12MHz as at 10KHz. Michael VE2BVW |
Michael Black wrote:
Somewhere in this thread, the 8038's more recent spawn was mentioned. Obviously, it will work over that full range, but I'm suspicious about how good it will be at radio frequencies, as I would about any RC oscillator. It seems a stretch to expect it to work as well at 12MHz as at 10KHz. I agree. But on the other hand if you controll this 8038 with another PLL synthesizer, i think the overall performance should be ok from 10 kHz to 12 MHz. I think that is the way how most of "pro stuff" works. |
Leigh W3NLB wrote: On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. Zero MHz is real easy, just throw a capacitor, transistor, resistor, tube, or any other electronic component on the bench. There, an oscillator that oscillators at zero MHz. |
The ARRL Handbook (any edition).
The Art of Electronics. Two of the best basic electronics books ever written Rob Tom wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom |
On Fri, 18 Jul 2003 07:16:07 -0700, W7TI wrote:
On Fri, 18 Jul 2003 14:05:06 +0200, "Tom" wrote: If you read my original post again or at least the topic, it says 0-12 (not 0, 12) MHz. And that would mean something in the range between 0 and 12. I don't remember when and WHERE i said that i need 0 MHz oscilator. The only one who talks about 0 MHz osc is you. _________________________________________________ ________ Perhaps English is a second language for you, but when you say 0-12 that will be taken to mean those two frequencies and everything in between. 0 hz is hardly a 'frequency.' |
On Fri, 18 Jul 2003 14:05:06 +0200, "Tom" wrote:
Leigh W3NLB wrote: 12 MHz is easy. 0 MHz is really difficult. If you read my original post again or at least the topic, it says 0-12 (not 0, 12) MHz. And that would mean something in the range between 0 and 12. I don't remember when and WHERE i said that i need 0 MHz oscilator. The only one who talks about 0 MHz osc is you. Big thanks to all other people who gave me good starting points. I was thinking about some CMOS devices, but most of them are square output. Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. |
Paul Burridge wrote:
Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. Thank you Paul! This is a good hint. Can you tell me in which book did you learn it? I would really like to get into this stuff. Regards Tom |
Rob Judd wrote:
The ARRL Handbook (any edition). On its way here... The Art of Electronics. I have this one and im not too happy with oscillator chapter. However, this is still one of the best books i've seen. Regards Tom |
On Sat, 19 Jul 2003 06:47:32 -0700, W7TI wrote:
On Sat, 19 Jul 2003 12:42:02 +0100, Paul Burridge wrote: 0 hz is hardly a 'frequency.' __________________________________________________ _______ Of course zero Hz is a frequency. Have you ever had a checkbook balance of zero? Is that not a balance? :-) Frequently!!! :-) -- Ken Knox N1JRO -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- |
A perfectly symmetrical square wave doesn't contain any even harmonics.
For best results when using this technique to generate even harmonics, the square wave needs to have a longer "on" period than "off" period or vice-versa. Roy Lewallen, W7EL Paul Burridge wrote: Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. |
"Tom" wrote in message ... Paul Burridge wrote: Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. Thank you Paul! This is a good hint. Can you tell me in which book did you learn it? I would really like to get into this stuff. IMO you are being led astray. I don't see why the emphasis on frequency multiplication. It is fairly simple to make an LC oscillator cover a 2 to 1 frequency range, or even 3 to 1. That could mean 4 to 12 MHz in one tuning range and 1.3 to 4 in another. The problem is lower frequencies. These days it is hard to find a large-enough variable capacitor for operation down in the few-hundreds of kilohertz range, let alone lower. I know of only two ways that will cover the whole zero to 12 MHz range without bandswitching or switched filters. One is the direct digital synthesizer DDS. Single chip DDS units are available [Analog Devices Inc] fairly cheaply, but they are tiny and require a computer or equivalent to control them. You get "perfect" frequency accuracy and stability and a sine-wave output. The other is a beat-frequency method with two oscillators operating considerably above 12 MHz. One crystal controlled, the other knob controlled tuning from the crystal frequency to 12 MHz higher. Feed them into a double-balanced mixer (MiniCircuits) followed by a low-pass filter that passes 0 to 12 MHz, and strongly rejects the crystal osc frequency and all higher. One knob, no switching, no computer needed for control - but also much poorer frequency accuracy and stability. |
"Leigh W3NLB" wrote in message ... On Thu, 17 Jul 2003 19:11:57 +0200, "Tom" wrote: Hello If anyone can recommend me a good book from which i will learn to construct oscillator that for example covers range 0-12 MHz. Thanks in advance! Tom 12 MHz is easy. 0 MHz is really difficult. I have a couple of those. They put out significant power. -- ... Hank Hank: http://horedson.home.att.net W0RLI: http://w0rli.home.att.net |
On Sat, 19 Jul 2003 17:39:23 GMT, John Popelish
wrote: Paul Burridge wrote: Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. This works pretty good at the third and fifth harmonics, but there is no second or fourth harmonic in a perfect square wave. Good point, John. But fortunately, I've never generated a *perfect* square wave! :-) In practice, it's probably more accurate to say that the even harmonics are well down on the odds. Blame it on dv/dt. |
On Sat, 19 Jul 2003 17:56:55 +0200, "Tom" wrote:
Paul Burridge wrote: Feed the square output to a coil+capacitor in parallel and you'll get a sine wave. Tune the this 'tank' circuit for harmonics of the funamental and you can double, triple, quadruple and so on the original square wave's frequency. Thank you Paul! This is a good hint. Can you tell me in which book did you learn it? I would really like to get into this stuff. Check out 'RF Circuit Design', by Chris Bowick. It's an excellent read on the subject of RF in general. |
Ken Knox wrote:
On Sat, 19 Jul 2003 06:47:32 -0700, W7TI wrote: On Sat, 19 Jul 2003 12:42:02 +0100, Paul Burridge wrote: 0 hz is hardly a 'frequency.' __________________________________________________ _______ Of course zero Hz is a frequency. Have you ever had a checkbook balance of zero? Is that not a balance? :-) Frequently!!! :-) I believe this proves that negative frequencies exist!! Rob |
Rob Judd wrote:
Ken Knox wrote: On Sat, 19 Jul 2003 06:47:32 -0700, W7TI wrote: On Sat, 19 Jul 2003 12:42:02 +0100, Paul Burridge wrote: 0 hz is hardly a 'frequency.' _______________________________________________ __________ Of course zero Hz is a frequency. Have you ever had a checkbook balance of zero? Is that not a balance? :-) Frequently!!! :-) I believe this proves that negative frequencies exist!! Rob Yes, it does. I just now sent you a message from the future on a negative frequency. You should be getting it yesterday. Hey, I should make a movie! Called "Frequency"! 73, Dave KZ1O -- Please yank that last "t" from my email address. It's "net", not "nett". You know how to do that, but the spammers won't. |
"W7TI" wrote in message ... On Mon, 21 Jul 2003 19:34:55 GMT, Dave Bushong wrote: I'm still stringing up my 0 MHz half-wave dipole. 468/f db kz1o __________________________________________________ _______ You will never finish. Sorry. :-) -- Bill, W7TI It could be shortened by the use of N turn loading coils, where N - infinity. -- ... Hank Hank: http://horedson.home.att.net W0RLI: http://w0rli.home.att.net |
Dave Bushong wrote:
I believe this proves that negative frequencies exist!! Yes, it does. I just now sent you a message from the future on a negative frequency. You should be getting it yesterday. Errm.... can i get a copy ? |
Old DXer wrote:
Yes, it does. I just now sent you a message from the future on a negative frequency. You should be getting it yesterday. Errm.... can i get a copy ? Careful -- you may end up in swaddling clothes and have to do it all over again. Kirk Over!! Picard - Make It So! Ok, see you on USS Eldridge. I can't wait to finally meet Tesla, Townsend Brown and Einstein. They must be somewhere on the ship! |
Tom wrote:
Old DXer wrote: Yes, it does. I just now sent you a message from the future on a negative frequency. You should be getting it yesterday. Errm.... can i get a copy ? Careful -- you may end up in swaddling clothes and have to do it all over again. Kirk Over!! Picard - Make It So! Ok, see you on USS Eldridge. I can't wait to finally meet Tesla, Townsend Brown and Einstein. They must be somewhere on the ship! Sure. They're down in the games room, watching the 3D television that Philo T. Farnsworth just invented. :) |
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