EMRFD Message Archive 9906
Message Date From Subject 9906 2014-04-10 08:11:12 Alberto I2PHD Wide range oscillator Greetings all,
I am in search of the schematic of a simple LC oscillator, using easy to find parts,
whose C component could range from, say, 1000 pF to 10 uF with the oscillator
working without problems on the entire range.
The L component is not critical, a value of 60 uH would make the oscillation frequency
from about 650 kHz (with 1000 pF) to about 6500 Hz (with 10 uF).
You have already guessed the purpose... I want to replicate the AADE LC meter, but with
an extended range and using a Stellaris board complete of a touch screen TFT display
as a controller. If I obtain satisfactory results, all will be published open source.
Thanks for any suggestions
73 Alberto I2PHD
Credo Quia Absurdum Est Credo Ut Intelligam
9907 2014-04-10 08:23:04 Roelof Bakker Re: Wide range oscillator Hello Alberto,
Can you give the frequencies you need for the LC meter?
9908 2014-04-10 09:22:11 Alberto I2PHD Re: Wide range oscillator 9909 2014-04-10 10:05:29 Roelof Bakker Re: Wide range oscillator Hello Alberto,
10 uF is a bit unwieldy for a LC oscillator.
Can't you use a NE555 type oscillator?
9910 2014-04-10 10:13:08 Alberto I2PHD Re: Wide range oscillator 9911 2014-04-10 10:29:56 Leon Heller Re: Wide range oscillator 9912 2014-04-10 10:44:29 Alberto I2PHD Re: Wide range oscillator 9913 2014-04-10 10:58:43 Leon Heller Re: Wide range oscillator 9914 2014-04-10 13:14:30 Sandeep Lohia Re: Wide range oscillator Hi Alberto,
what U thinks ( TFT display ), components might not be available
Here I used internal oscillator of more economic PIC...
http://www.qsl.net/vu2upx/Projects/2tosc.htm as I know that site is
no longer maintained by Charu...
btw, I did forward your mail to him, good in codes too...
Please encourage recycling, reuse or repairing of E-waste.
░7░3░ ░d░e░ ░V░U░3░S░X░T░
9915 2014-04-10 13:55:00 Alberto I2PHD Re: Wide range oscillator 9916 2014-04-10 14:08:33 Alberto I2PHD Re: Wide range oscillator 9917 2014-04-11 03:15:23 g3wie Re: Wide range oscillator Hi Alberto,
Here's a "cascode" oscillator circuit which oscillates from kHz to a few hundred MHz using a negative-resistance simulation. This was published in the GQRP magazine SPRAT by LZ1OV, and republished a couple of years ago with a PCB layout. Stefan made some PCBs and I kitted them up and sent them to GQRP to sell in their shop, though it would be better to build it ugly-style for the best VHF performance. The output waveform isn't too nice; adjustment of the bias values might improve it. Apart from the tuned circuit, there are no frequency-sensitive components.
I couldn't see how to attach the schematic to this post so perhaps this link will work (it's in the G3WIE folder in files)
wrote :Greetings all,
I am in search of the schematic of a simple LC oscillator, using easy to find parts, whose C component could range from, say, 1000 pF to 10 uF with the oscillator working without problems on the entire range.