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Re: Does anyone have a good sub for the LM389?
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Re: Does anyone have a good sub for the LM389?
Rick is correct, use an LM386 with discrete transistors. Simple 2N3904's should work fine, matching is not really critical. Thermal stability will probably suck no matter what transistors you use, but use good caps (polystyrene or polypropolene) to minimize thermal drift.
- CarlComment
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Re: Does anyone have a good sub for the LM389?
Rick is correct, use an LM386 with discrete transistors. Simple 2N3904's should work fine, matching is not really critical. Thermal stability will probably suck no matter what transistors you use, but use good caps (polystyrene or polypropolene) to minimize thermal drift.
- CarlComment
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Re: Does anyone have a good sub for the LM389?
Rick is correct, use an LM386 with discrete transistors. Simple 2N3904's should work fine, matching is not really critical. Thermal stability will probably suck no matter what transistors you use, but use good caps (polystyrene or polypropolene) to minimize thermal drift.
- CarlComment
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Thanks guys, sounds like this is more my speed for now +
I saw the reference to the lm386 my fourth time through. I will be happy to have a submersible PI unit running by May or early June.
SComment
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Thanks guys, sounds like this is more my speed for now +
I saw the reference to the lm386 my fourth time through. I will be happy to have a submersible PI unit running by May or early June.
SComment
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Thanks guys, sounds like this is more my speed for now +
I saw the reference to the lm386 my fourth time through. I will be happy to have a submersible PI unit running by May or early June.
SComment
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Re: Does anyone have a good sub for the LM389?
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Re: Does anyone have a good sub for the LM389?
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Re: Does anyone have a good sub for the LM389?
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Lets Build A Proton Magnetometer! I Need Everyones Input!
I have researched and researched until I am blue in the face! I am looking for some insight to some detailed plans on building a proton magnetometer. There are a lot of beginners out here who cannot translate a schematic into a working model. I have read Jim Koehler's work, Dan Fountai's Page, and the Home Grown Proton Magnetometer, and Huggards Mag from 1970.
Lets see if we can't take the wisdom of this forum and devise a working model with parts list etc. Those of you who have working mags can pitch in and lend us beginners a hand.
Specifications:
Sensor:
Toroidal Sensor using "Rack-a-Stack" blue ring or PVC 45 deg. Elbows.
Control:
Controls should be automatic with audio and meter readout.
Lets see if we cant come up with some step by step specifics on how to build a working proton magnetometer, not just schematics to be deciphered!Comment
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Re: Lets Build A Proton Magnetometer! I Need Everyones Input!
Robert . It seems like a nice idea . I am an Autodidact on the subject but have worked quite a bit on the Proton Magnetometer . I also would like the input of some ,,Brains ,, on the subject . I hope we can find the master to help us all . May I suggest the J.A.Koehler Mag as a starting point . It is a quite simple design and should work pretty good in my opinion . To read the schematics is no problem . I even changed the pulse train used in the design . I made the printed circuits as far as I needed them etc.etc. . This sounds like a real nice project . Another suggestion I have is to work on three different parts of the mag and not on all together . So ... sensor ..then the Amplifier .. then Registration . What is your idea ? Regards CorneliusComment
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Re: Lets Build A Proton Magnetometer! I Need Everyones Input!
Cornelius,
I would love to see some of your work on the Proton Mag. I understand the schematics but puting them into printed circuits is another story. If you have some designs you could share that would be great.
I am all for using Jim Koehlers design. I just ordered 600feet of #20 AWG wire and will be starting my "Rack-a-tack" toroidal sensor this weekend.
But I have also considered using 8 - 1 1/2" 45 deg elbows. I figured I could make each side by joining 4 elbows and winding the coils around each half. This would be much faster than trying to wind the blue ring. I could then join the halves and connect the coils in series.
So once the sensor is complete, where do we go next?
Thanks,
RobertComment
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Re: Lets Build A Proton Magnetometer! I Need Everyones Input!
The elbows I have suggested in this forum . The difference from your approach is that I wind eight coils on seperate coilbodies . These coils will slip over the thick end of the elbows . So I wind the coil and make it one part with the elbow . Now when I glue the elbows together I have a full toroidal coil . This is the simplest way because the coils can be wound on a regular form , on a regular machine . Now you also have eight ways of connecting your coils ( amps ! ) . Let us see if other folks are interested . The first tip you have now . Regards CorneliusComment
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Re: Lets Build A Proton Magnetometer! I Need Everyones Input!
I am making Phil Barnes' mag, I wound two of the blue rings with 14awg, took about 6 hours each and had my hands swollen and hurting. I plan to adapt the whole thing for hunting shipwrecks. So far I have found a few problems(nothing serious) with Phil's schematics and diagrams, and still have not gotten it to work, but I havnt had it together for very long now either, Im sure it will work soon. Jim Koehler's design seemed a bit complicated for a first timer like myself but it also seems like a darn good one! Any information or suggestions would really be appreciated,
CraigComment
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