GS 5 THRESHOLD PROBLEM

[Ferric Toes]

Hi Eric...i will try what you said and connect the -10v to the output connection of the 79L12 regulator...i did find for some reason that if i were to decrease the supply voltage down below 12 volts then the threshold level would start to decrease slightly...not really sure why that should happen.

Hi Dave,
Basically, trying to run that circuit at 12V input is bound to cause problems. You have to raise the voltage to 14-15V for it to be stable. The Whites TDiSL runs at 12V and necessary circuit changes have been made, but I do not have the details. I believe from reports that the performance is not quite as good as the GS5B based TDi.

Eric.

[daverave]

Hi Dave,
Basically, trying to run that circuit at 12V input is bound to cause problems. You have to raise the voltage to 14-15V for it to be stable. The Whites TDiSL runs at 12V and necessary circuit changes have been made, but I do not have the details. I believe from reports that the performance is not quite as good as the GS5B based TDi.

Eric.

Hi Eric...ive been using 4 li-ion batteries 15v and i was hoping that i could use the detector down to at lest 11 volts before recharging...ive had another idea of using a small SM minus LD adjustable regulator with a drop out of about 300 mV to just supply the audio board which in theory should work....ive had to order one and i hope it may do the trick with the threshold drift....do you think it may solve the problem ???

[kt315]

ive been using 4 li-ion batteries 15v
--
i put only one word DV. ive been using 4 chinese li-ion batteries 15v

[eclipse]

The TDI SL has audio based on 4066 and 555 and 3 additional op amps. It doesn't use 79L12.

[kt315]

You have to raise the voltage to 14-15V for it to be stable.
---
Eric, in my elite i LEFT LM2931-ADJ on board. now i think to delete it. a converter gives 13V on output. from 3.7V to 13V. enought reserve on voltage.
you can believe me or not.

[kt315]

you can NOT believe me and thinking thats Photoshoped.

[kt315]

photoshoped. i use chinese low price drop charger for 18650, just added wire+connector.

[daverave]

You have to raise the voltage to 14-15V for it to be stable.
---
Eric, in my elite i LEFT LM2931-ADJ on board. now i think to delete it. a converter gives 13V on output. from 3.7V to 13V. enought reserve on voltage.
you can believe me or not.

Hi kt315....im not keen on chinese li-ion batteries as many are not what they rated to be....as an example some years ago i bought some li-ion rated at 6000 mAH and when i tested them they were only about 800 mAH....so i no longer buy li-ion batteries from china...a lot of my batteries ive got from laptop battery packs....i really want the GS 5 to run from 15v down to 11v....even at 11 volts the detector gives good depth but with the drifted threshold.

[dbanner]

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.

[dbanner]

The TDI SL has audio based on 4066 and 555 and 3 additional op amps. It doesn't use 79L12.

Interesting, 555 instead of AD654, 4066 instead of Jfet's. Not much in it.

[kt315]

you simply do now want to hear me. you try to fix a problem HEAD ON. or, we want to fly on Mars. then we must to icrease of power of our
rocket. LOL! so WHY aliens EASELY fly around you from space and into space on their fliyng saucers? no answer.
just impulse gives HIGH ADVANTAGE. LOW POWER CONSUMPTION. LOW ENERGY CONSUMPTION. if you have an engine with UNLIMITED energy
you can fly in space and from space EASELY! Elon Mask is CRYING looking on UFOs in the sky!

LEARN THAT MATTER. learn electronics - filos did call me PROFESSOR. THE PROFESSOR. and yes, i am the pro.

[kt315]

your 5pcs un-chinese li-ion bats are ready to start. LOL!!!

[dbanner]

https://www.ebay.com/itm/Mini-DC-DC-...BMJQ:rk:2:pf:0

use

typical efficiency 82%. PERFECT!

Very good price. Very small. Very cool. Very Chinese. Do they carry the positive version?

[kt315]

[kt315]

Very good price. Very small. Very cool. Very Chinese. Do they carry the positive version?

if you connect it between batt and board (between source and consumer) you do not have to think about the polarity. plus on plus.
minus on minus.