GS 5 THRESHOLD PROBLEM

[dbanner]

What about charging?

[daverave]

ive used those converters from china and yes they are very good but somewhat power hungry.

[kt315]

android phone 'charger in your opinion' microUSB plug gives +5V sure. so this is NOT charger but a stabilizer of just +5V. a charger micro sets in THE PHONE ON ITS BOARD ITSELF. if you put it in your detector you can charge li-ion from this power supply. use balansir board, its simplest way.

[eclipse]

Dave the problem is not the converter efficiency but the fact that where they are not synchronized they pour in too much noise.
I don't recommend using them at all if you can sync them with the TX cycle.

[daverave]

I don't think I will be hunting at temperatures above 30 degrees Celsius, better to be indoors.
So from advise, it looks like easy mod. Loose the 79L12, connect instead to -10V, then change 337 to 2991.

the lm 2991 looks a good choice and could solve the threshold problem...i think the SM version would be a better choice than the TO220 type.

[dbanner]

the lm 2991 looks a good choice and could solve the threshold problem...i think the SM version would be a better choice than the TO220 type.

You could find a bunch of smd regulators in old add on boards from old PC stuff.
But they're rated only around 100ma. You need something rated @1A, hence TO220.

[kt315]

You could find a bunch of smd regulators in old add on boards from old PC stuff.

America can use bunch of Soviet era rockets engines on the its modern heavy rockets like DELTA IV.
give new life to oldest stuff.

[kt315]

Dave the problem is not the converter efficiency but the fact that where they are not synchronized they pour in too much noise.
I don't recommend using them at all if you can sync them with the TX cycle.

if much noise do not use android phone, PC, LCD monitor, LED lamps. turn off all around you. live in darkness.
turn on a radio and hear a cosmic noise. this noise is going from Milky Way amigo.

[kt315]

noise on Mars. but why they are like children joy on just noise?? https://www.youtube.com/watch?v=yT50Q_Zbf3s

[dbanner]

Dave the problem is not the converter efficiency but the fact that where they are not synchronized they pour in too much noise.
I don't recommend using them at all if you can sync them with the TX cycle.

Is it noise emitted from device by air, or is it noise(ripple)(switching noise) in the line itself? I read their is some noise in the line but couldn't it be filtered out, or wouldn't it be beyond the range to matter, or wouldn't the inherent filtering in the MD circuits take care of it?
I think problem might occur with input noise to converter if tx and buck converter share same battery. Then I think I see what you mean by synchronized. Input noise from tx would appear on output of converter.

[daverave]

You could find a bunch of smd regulators in old add on boards from old PC stuff.
But they're rated only around 100ma. You need something rated @1A, hence TO220.

i would use the LM 2991 SM version just for the audio pcb and leave the LM 337 as in Eric's spec.

[eclipse]

lots of videos on youtube to show the ripple noise and all switching regulators have those do some research. https://www.youtube.com/watch?v=nVIpDIIiuF8
sure you can filter it RC/LC filters and such but it's still there no matter what, except if you can't sync it with TX cycle.

on pulse induction metal detector this noise is highly unwanted if you want to get stability.
curing one problem (unstable threshold) by introducing new problem (supply voltage noise) is not very wise.

[dbanner]

Is it noise emitted from device by air, or is it noise(ripple)(switching noise) in the line itself? I read their is some noise in the line but couldn't it be filtered out, or wouldn't it be beyond the range to matter, or wouldn't the inherent filtering in the MD circuits take care of it?
I think problem might occur with input noise to converter if tx and buck converter share same battery. Then I think I see what you mean by synchronized. Input noise from tx would appear on output of converter.

Re- read my post. I see your point. Second issue would be noise generated by converter itself which cannot be synchronized with tx with off the shelf converter.

[kt315]

Is it noise emitted from device by air, or is it noise(ripple)(switching noise) in the line itself? I read their is some noise in the line but couldn't it be filtered out, or wouldn't it be beyond the range to matter, or wouldn't the inherent filtering in the MD circuits take care of it?
I think problem might occur with input noise to converter if tx and buck converter share same battery. Then I think I see what you mean by synchronized. Input noise from tx would appear on output of converter.

your words must be heared by Whites Electonics Company, Garrett, First Texas, ML. really they are all downito idiotics if using not low drops but convertes in every detectors they manufacture novaday.

[dbanner]

your words must be heared by Whites Electonics Company, Garrett, First Texas, ML. really they are all downito idiotics if using not low drops but convertes in every detectors they manufacture novaday.

Thanks for your reply. Yes, they are all idiots. Satisfied?
They are stupid enough to engineer solutions to issues because they are dumb enough to embrace more sophisticated technology and find custom solutions which are now economically viable, whereas before they were not. And they must be morons for looking to minimize cost and maximize profits in such a competitive market.
I wouldn't be surprised if the idiots are using sm ferrite beads for filtering on their primitive low tech devices including building PCBs with inductive tracks for noise suppression. Primitive indeed.
We kitchen table scientists must be superior to those idiots.