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Re: good scopes for coiling



Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

Just use two normal LEDs in anti-parallel (like back to back). Hook the meter in series with one of the LEDs which will rectify the current for you QED (quite easily done)... It will be about 5mA of current so play with the meter shunts or whatever for about that level. The voltage is 0 to 9 volts. There is a dropping resistor in series with the LEDs too that can be adjusted at will.

Cheers,

        Terry


At 09:10 PM 5/18/2005, you wrote:
Malcolm,
Yes, my intent is to rectify the AC output and feed it to the meter. One problem is that I don't have any idea what the output voltage is and whether or not I might get dropouts, if the level drops lower than the forward voltage drop of the diode(s). I am assuming that since the output has to drive the LED, it is high enough.


My problem is that trying to judge the output level by the relative brightness of the bipolar LED is not a very good option for me because of my extremely poor vision. I'm not sure that I will be able to do this at all. I was hoping that I could use a very simple rectification because I'm not looking for any particular accuracy. I just want to use the meter to indicate the signal strength as it fluctuates so that I can find the maximum point. If this is all I am doing, can I just use a Schottky diode as a half-wave rectifier and feed this to the meter? The problem here is I will compound any problem I might have with a low signal level, cutting it in half with the rectifier. I think what I'll do now is just start trying things. I have nearly completed the tuner itself. I only need to solder the connections to the LED and I'm through. I will try the half wave rectification with a Schottky diode first and see what I get and go from there. Thanks.
Paul
Think Positive


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From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Wednesday, May 18, 2005 6:56 PM