Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: An Interesting FM/AM Detector Using An NE567  (Read 7048 times)
TANAKASAN
Member

Posts: 933




Ignore
« on: September 28, 2012, 08:02:49 AM »

I was looking for a way to calculate NE567 Tone decoder values and I came across this interesting circuit:

http://www.amalgamate2000.com/radio-hobbies/radio/ne567_tone_decoder_as_am_fm___de.htm

OK, so it only works at 455 KHz but with one IC and eight other components you get a NBFM detector and a synchronous AM detector and no inductors required. Useful if board space is limited.

Tanakasan
Logged
WB6BYU
Member

Posts: 15666




Ignore
« Reply #1 on: September 28, 2012, 09:33:04 AM »

Very interesting:  I'll have to try it out.  Allows a simple switch between AM and FM
output for a receiver.
Logged
KB3HG
Member

Posts: 404




Ignore
« Reply #2 on: October 02, 2012, 08:15:11 AM »

Nice
Logged
W8ADQ
Member

Posts: 36




Ignore
« Reply #3 on: April 01, 2015, 04:02:02 PM »

Cool stuff! Back in 1972, Signetics published a booklet on their then-new NE560 NE561 NE565 AND NE567. My memory is a bit dusty and I don't remember if the NE564 came later.  I think there was also an NE566 which only had the VCO of the NE565 brought out to pins.  It was a big brown book though not too thick with green print.  Maybe you can find a scan.  Mine is long gone.

This thread tripped a memory.  The book had a table comparing the NE56x series features.  Either the NE561 or the NE560 had a demodulated AM output that had been optimized for linearity.  Now unobtainable...sigh.  HOWEVER, it also indicated that the NE567 had both FM and AM but not optimized for linear demodulation.  I tinkered with it a bit back then, and also played with a sample and hold capturing the tiny positive peak window for best S/N.  The simple 567 as a tone decoder would lock onto the carrier rock solid and I used old style one shots with trimpots to set the capture window based on the PLL.

If you can find the old book, it will give you a lot of ideas that can be used with both the older PLLs and the newer ones.  Anyway, the 567 can be a lot of fun in the world below 500 KHz.

73 de Jack W8ADQ  Smiley
Logged
N8CMQ
Member

Posts: 602




Ignore
« Reply #4 on: April 03, 2015, 09:13:28 PM »

I am getting too old...
When I first read this, I thought, 'How would a neon lamp do that?'...
I was thinking of the NE51 lamp and how I used them as voltage regulators and relaxation oscillators.
Then I read the article, but I googled NE-51 and did some reminiscing!
I believe you can do the same with a CD4046, and at higher frequencies.
Logged

N8CMQ   Jeff Retired...
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!