Comments are moderated before they will appear on the website, this is a manual process and may take some time. Please be patient.
Author Name is a required field.
Email Address is optional, but without one I won't be able to contact you back. It is never shown or linked on the website. You can always just email me if you'd rather not post a public comment. I generally reply in-line with a comment rather than email you back, unless I want to discuss something in private or off topic. Please check back to see when I reply.
Website URL is optional, if supplied the Author Name will be hyperlinked to this URL.
You may use wikitext in the body, preview may be handy here. Don't worry if you can't figure them out, just give me a hint what you want linked to what and I'll do it during moderation. Wikitext is not BBcode!
Spammers: Please don't bother wasting your time scripting up posts to this form. Everything is moderated, your post will never be seen on the web even transiently, there is no way to even view it by its internal ID, it will never be indexed. I will simply delete your post in the moderation interface. If I'm your target audience you're really on the wrong track; I'll never click on a URL in your garbage. The post content is not emailed to me (and I don't use a Win32 mail client anyway), I view the posts in plain text in the moderation interface so no clever tricks of any kind will make anything you type be interpreted by anything other than me, a human. Just give up and go elsewhere please!
27th June 2013 02:52
Hi, a very late reply...
I found your solution to a ratio detector here as a very interesting variation. Maybe I have a solution to your asymmetry problem. Point is that a tank on the diodes side is supposed to run at ~90° against the middle connection input. It was achieved by very loose coupling to the primary, or otherwise you'd lose the ability to shift phase about the resonance. Phase shifting the middle connection does not do the trick because you are after resonance. Such loose couplings are very impractical, and that's the main reason for ratio detector's demise.
You could provide some alternative mode of coupling that does the trick. A toroid provides near perfect coupling for the bifilar coil.
11th March 2013 15:37
To construct a stable 2 mtr local oscillator, use the third overtone of a 14 mhz microprocessor crystal into a tripler stage. 14.8 x 3 = 44.4 mhz. 44.4 x 3 = 133.2 which brings you close to a 10.7 mhz if.
15th November 2011 23:02
Hello Alan,
I recall you having some odd kind of J310 JFETs with Idss ~ 100mA and Up -3.6V or less. Is the same batch also used here for the VCO buffer stage?
I'm not sure what's up with those 100mA Idss JFETs (maybe rebadged PN4391?) either, but genuine J310s tend to have pretty uniform Idss round 40mA. That's also what I use. Philips (PMBF)J310 ones are an exception. Lower avg Idss and more variation.
13th January 2011 04:55
you did a great work. why don't you try ratio detector as it works much better than yours one. you can use a Ratio detector coil. if you need any help to build Ratio detector coil let me know I can help you.
13th May 2014 19:53
Gary Grove wrote...