LC filter combination for 19mhz signal
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

 Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
 25th July 2005, 11:18 PM #1 LeakSt20   diyAudio Member   Join Date: Jul 2005 Location: London LC filter combination for 19mhz signal Hi, Am trying to build a stereo decoder for my Leak Troughline II tuner, using the following circuit diagram at: http://werple.net.au/~kiewavly/Leak/stereo_dec3.gif My problem is there is no L C combination shown on the diagram. I have worked out that if I use a 1mh inductor I can use a 17.5nf cap: If L, is 1milliHenry, then C = 1 / ( L* ((Fo * 2 * pi )^2)) = 1 / (0.001 *( (19000 * 2 * 3.14 )^2)) = 17.5 nanoFarads but am not sure, my maths insn't great. Also could I use a 20nf cap with 20% tolerance to get the 17.8 - 22.2 nf range I need with the 1mh inductor? Has anyone out there created this circuit? If so what combo did you use, if you used one. I have also heard that I could use an RC filter instead of an LC filter, and this would be easier. Any help here would be appreciated. Thanks LeakST20
 26th July 2005, 08:00 AM #2 LeakSt20   diyAudio Member   Join Date: Jul 2005 Location: London Sorry I meant to say 19Khz not 19mhz.
 26th July 2005, 08:22 AM #3 Frank Berry   diyAudio Member     Join Date: Sep 2003 Location: Midland, Michigan 1 mH and 70 nanoFarads will resonate the circuit at 19 kHz. __________________ Frank
Frank Berry
diyAudio Member

Join Date: Sep 2003
Location: Midland, Michigan
Below is a plot of the filter.
Attached Images
 19 khz filter.gif (8.1 KB, 85 views)
__________________
Frank

 26th July 2005, 01:29 PM #5 LeakSt20   diyAudio Member   Join Date: Jul 2005 Location: London Thanks very much Frank
 8th August 2005, 02:58 PM #6 LeakSt20   diyAudio Member   Join Date: Jul 2005 Location: London The 1mh 70nf LC filter assumes less then 1% tolerance in order to resonate at 19Khz. The capcitor I have has is 68nf with a tolerance of 5% (anywhere from 64nf to 71nf ) and so does the 1mh choke. Is there any way I can gurantee 19khz, perhaps using a smaller capacitor value, trimmer etc. I appreciate any advice you can give. leakst20

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Site     Site Announcements     Forum Problems Amplifiers     Solid State     Pass Labs     Tubes / Valves     Chip Amps     Class D     Power Supplies     Headphone Systems Source & Line     Analogue Source     Analog Line Level     Digital Source     Digital Line Level     PC Based Loudspeakers     Multi-Way     Full Range     Subwoofers     Planars & Exotics Live Sound     PA Systems     Instruments and Amps Design & Build     Parts     Equipment & Tools     Construction Tips     Software Tools General Interest     Car Audio     diyAudio.com Articles     Music     Everything Else Member Areas     Introductions     The Lounge     Clubs & Events     In Memoriam The Moving Image Commercial Sector     Swap Meet     Group Buys     The diyAudio Store     Vendor Forums         Vendor's Bazaar         Sonic Craft         Apex Jr         Audio Sector         Acoustic Fun         Chipamp         DIY HiFi Supply         Elekit         Elektor         Mains Cables R Us         Parts Connexion         Planet 10 hifi         Quanghao Audio Design         Siliconray Online Electronics Store         Tubelab     Manufacturers         AKSA         Audio Poutine         Musicaltech         Aussie Amplifiers         CSS         exaDevices         Feastrex         GedLee         Head 'n' HiFi - Walter         Heatsink USA         miniDSP         SITO Audio         Twin Audio         Twisted Pear         Wild Burro Audio

 Similar Threads Thread Thread Starter Forum Replies Last Post kelticwizard Instruments and Amps 15 7th February 2006 01:58 AM sardonx Tubes / Valves 8 27th August 2005 11:16 AM cathode_leak Tubes / Valves 3 12th May 2005 09:32 AM Peter Daniel Chip Amps 45 8th November 2004 12:47 PM

 New To Site? Need Help?

All times are GMT. The time now is 10:20 PM.