Current in the transmission circuit

[Artyom]

Hi, everybody. Topic for discussion. An important factor of deep and high-quality search by a metal detector is the current in the transmitter circuit. Propose a share information from personal observations. Who what talk uses and on any soils. The dependence of the current frequency, etc.

[sheekh]

hi for every body in this great form :
while Iam building tm808 do some test to current pass throw the tx coil throw THROW ( 2N2907) changing the resistor at the emitter as flow
1- R =82.5 OHM 0.25W detection depth 60 cm TX CONSUMPTION 66 mA
2- R = 41 OHM 1WATT DETECTION DEPTH 120 CM TX CONSUMPTION 90 mA
3- R = 25 OHM 4 WATT DETECTION DEPTH 180 CM TX CONSUMPTION 190 mA

SO i NEED TO INCREASE THE THE POWER ANOTHER 50-100 m A BUT HOW ?
WITH GREAT PEOPLE HERE NOTHING IMPOSIBLE
REGARDS
SHEEKH

[kt315]

one way ticket. to transfer from VLF*** type detector to PI one. PULSE INDUCTION can give you more TX energy in the coil,
practically unlimited, or limited just your battery quality.

i'm kt315.

** TM-808, TF900, TM800, TF600 are VLF-TR type detectors.

[sheekh]

Welcome KT
&thanks for straight reply
But I what I mean in the same configuration that used in tx for tm808 ,like using anthor transistor with high Ic 0.8 or 1 amps like AC128 it will increase the power in the tx coil
Regards
Sheekh

[waltr]

There has been much discussion about 'higher power' VLF detector oscillations in the forums.

Read through ALL of the TGSL, IDX and IGSL Threads for some of the discussion.

[sheekh]

THANKS WALTER , i dont think i will read 4000 thsdns page to find this , I new in this field some guide lines may help .
or it seems I came late to this fourm . & people here finish discussions and modifications and they are busy now with metal detector chargers

since there is extra power in the power supply around 200 mA, I need to increase the power by 100 mA to increase
the detection depth fro tm808 the attached clearly the idea IF IT POSSIBLE OR NOT , OR THERE NANY SUGESTION
THANKS FOR HELP
BEST WISHES
SHEEKH

[kt315]

1. use STEP UP converter for last TX stage, on 60V output. you get more signal amplitude.
2. another way showed in this sch. connect 1/4 of TX coil (L1) to driver. you get more signal amplitude on TX coil.

[sheekh]

many thanks KT, this is long story , also its not clear parts and language.
any way I read about TX- nexus in this forum it has 100 vp-p, MY QUESTION I can use it with the same power supply IN TM808 and if it I take small part of signal FOR CHOPPING it will have effect on the other chips or IN NEED TO MAKE TRANSFORMER TO REDUCE THE VP-P
REGARDS
SHEEKH