Minelab Excalibur 1000 very weak detection problem

[Micheal]

hi guys ..my minelab excalibur 1000 stopped working...i finally realised the coil was bad...i changed the coil and put on a new soveriegn tornado coil.The good news is the detector is working(so I am very happy about that).
The problem now is the excalibur is only detecting very weak,for example a large pair of pliers can only be detected at 3 cm maximum.the threshold works perfect ,the discrimination works perfect,volume works perfect ..everything works perfectly...just the detection is very weak ...i have checked baterries all is perfect even under load is perfect...all the pots function perfectly...
I have rang minelab and they told me they dont fix this model anymore..it is the blue excalibur with blue headphones ...(they told me to buy a new)
i have gone through the whole board and resoldered many of the components in case there is a dry solder somewhere but is still the same.I have changed the two 470uf capacitors ..still works the same ...all capacitors looks healthy...I am totally confused now im not sure if it is one of the IC's or a resistor ....

There is no schematics on the internet to go by I have rang woody from link teknologies but he doesnt fix them either...can anybody give me some help to fix it or where to look please ...thanks guys

[Qiaozhi]

hi guys ..my minelab excalibur 1000 stopped working...i finally realised the coil was bad...i changed the coil and put on a new soveriegn tornado coil.The good news is the detector is working(so I am very happy about that).
The problem now is the excalibur is only detecting very weak,for example a large pair of pliers can only be detected at 3 cm maximum.the threshold works perfect ,the discrimination works perfect,volume works perfect ..everything works perfectly...just the detection is very weak ...i have checked baterries all is perfect even under load is perfect...all the pots function perfectly...
I have rang minelab and they told me they dont fix this model anymore..it is the blue excalibur with blue headphones ...(they told me to buy a new)
i have gone through the whole board and resoldered many of the components in case there is a dry solder somewhere but is still the same.I have changed the two 470uf capacitors ..still works the same ...all capacitors looks healthy...I am totally confused now im not sure if it is one of the IC's or a resistor ....

There is no schematics on the internet to go by I have rang woody from link teknologies but he doesnt fix them either...can anybody give me some help to fix it or where to look please ...thanks guys

Rather than randomly soldering joints and replacing capacitors, you should debug the problem logically. Dry joints usually cause intermittent faults that can be traced by tapping, heating and/or cooling. In this case it sounds like a permanent fault.

First you should measure the power supply voltages using a multimeter. This can be done easily by probing the correct pins on any ICs you can identify. However, it is virtually certain that you will need an oscilloscope to fix this detector. You will need to check that it is transmitting correctly by monitoring the signal across the coil. If this seems ok, then move on to the receive section. Without a schematic it's going to be a hard problem to solve.

Also, try another coil before ripping the unit apart.

[philippehobby]

Hi,

Did you fix your problem, was the tornado coil compatible with Excalibur?
Philippe

[Waikiki_Sweep]

findmall.com has a dedicated "Minelab Sovereign Elite/GT and Excalibur Forum"
http://www.findmall.com/list.php?21
Ask them or search for answers.

Also it is unclear your detector was broken or new coil is incompatible. What if new coil is for Excalibur II.
I hope you will find answers. Or may be you can fix old coil to check at least that detector is OK.

Good luck!