LinkBack Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
  #10   Report Post  
Old April 28th 09, 04:02 AM posted to rec.radio.amateur.homebrew
external usenet poster
 
First recorded activity by RadioBanter: Feb 2009
Posts: 35
Default Experimenting with Coils for Crystal Sets

K7ITM wrote:


To put some numbers on what Paul suggested:

If I want an unloaded coil Q of 2000 at 10MHz,


I stopped here.


I'd expect to need a....

No way you'll ever see 2000 Q at 10 Mcs. Can't happen. Some guys are
approaching 2000 at 1 MC BCB but there's lots of expensive hoops to jump
through to reach that point. Simply cannot be had at 10 Mcs. 200-300
on a good SW coil is about all that can be achieved.



If you have very sensitive earphones (and sensitive ears!) and a good
antenna, what may matter more than keeping the loss down to an
absolute minimum is getting rid of interfering signals.


Thats Q.

=
It's a really good idea to check out what others have done to advance
the art of winding high Q coils for AM broadcast band frequencies, and
of the circuits to use those coils to best advantage.


Indeed. But that agreed to there's no method to make the same numbers
and techniques work at 10 Mcs. You really cannot achieve the numbers on
SW as you can BCB given the 10x frequency difference.


 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
OT...There are Crystal Sets,and then There are These Crystal Sets... rtc[_3_] Shortwave 4 November 8th 08 12:23 PM
3946 crystal to swap; wanted 3546 crystal Smokey Boatanchors 0 June 19th 06 02:25 PM
FA: Crystal calibrator circuit board w/crystal on Ebay GS Boatanchors 0 October 3rd 03 12:13 AM
FA: Crystal calibrator circuit board w/crystal on Ebay GS Boatanchors 0 October 3rd 03 12:13 AM
FA: Crystal calibrator circuit board w/crystal on Ebay GS Swap 0 October 3rd 03 12:13 AM


All times are GMT +1. The time now is 10:12 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017