Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives :: Books
Support This Site: Contributors :: Advertise


It is currently Oct Sun 21, 2018 3:33 pm


All times are UTC [ DST ]





Post New Topic Post Reply  [ 4 posts ] 
Author Message
 Post subject: Finding IF and tuned LC circuit frequencies
PostPosted: Jan Thu 04, 2018 5:14 am 
Member
User avatar

Joined: Aug Sun 02, 2015 7:34 pm
Posts: 884
Location: Yukon, OK USA
I built this simple circuit some time ago and still find it useful. You use a signal generator and meter to test the resonant frequency of a transformer or tank. I have used it to figure out IF cans from my junk box. I built it into a box and used a 200 ua meter which works well with my signal generator. The article said you could use a VTVM with it also. When you hit the resonant frequency you get a nice peak on the meter. Given an known value for C or L you could calculate the other components value. I have a frequency meter monitor my signal generator so my readings are pretty accurate. Cheap and easy to build.


Attachments:
freqfinder.jpg
freqfinder.jpg [ 63.54 KiB | Viewed 546 times ]

_________________
Rick
AB5ON

Forest Gumping through life
Top
 Profile  
 
 Post subject: Re: Finding IF and tuned LC circuit frequencies
PostPosted: Jan Thu 04, 2018 5:54 am 
Moderator
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 22458
Location: Somers, CT
I wonder why they included the RFC?

Pete

_________________
Just because it can be done doesn't mean it should be done.


Top
 Profile  
 
 Post subject: Re: Finding IF and tuned LC circuit frequencies
PostPosted: Jan Thu 04, 2018 3:32 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 7316
Location: 13 Critchley Avenue, PO Box 36, Monteith Ont, P0K 1P0
Isn't that pretty much a circuit for an RF probe as used on many VTVM's?

_________________
Looking for an old friend : Dan Lafleur. We attended Earl of March High School in Kanata together.


Top
 Profile  
 
 Post subject: Re: Finding IF and tuned LC circuit frequencies
PostPosted: Jan Thu 04, 2018 5:33 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 882
Location: Wayside, NJ Monmouth
I built this one to test IF cans, the frequency is always a bit low, but it get's you in the ball park. Just hook it up to a frequency counter.


Attachments:
IF_CAN~1.jpg
IF_CAN~1.jpg [ 34.94 KiB | Viewed 494 times ]
Top
 Profile  
 
Post New Topic Post Reply  [ 4 posts ] 

All times are UTC [ DST ]


Who is online

Users browsing this forum: Usually Lurking and 5 guests



Search for:
Jump to:  
























Privacy Policy :: Powered by phpBB