Power supply for relic hawk

LS 4S · Post by **LS 4S** » Fri Sep 17, 2021 8:56 pm

hi i have just purchased a relichawk with no power supply it has the lead with three bare wires so i need help identifying positive and neutral

Fusion · Post by **Fusion** » Sat Sep 18, 2021 8:36 am

Some searching on the web shows that it's power is a single 12 Volt lead-acid battery, capacity 1.2 Ah. The thick red and black wires to the PCB are the power connection wires, red=positive. There's a few obvious components that serve as guides to polarity, too. The big 3 amp diode is straight across the power wires, for 'reverse power connection' errors, so the end with the band joins the red power +12 Volt wire. The big electrolytic cap next to it is polarised, too, so cap -ve joins power -ve.
I've attached a few pics pilfered from the Geotech1 technical forum.
Other bits you may have include an inline fuse ( a good idea ) or some thermal switch type doohickey, and a proper On/Off switch.
I'd be inclined to change the lead gel-cell battery for a 10-cell NiMH pack, using AA size cells.

Here's the user manual for it:
https://www.kellycodetectors.com/pdf/ma ... icHawk.pdf

If you get stuck, post up some decent photos and we'll have a look.
And registering with Geotech1 is worth doing.

LS 4S · Post by **LS 4S** » Sat Sep 18, 2021 5:34 pm

Thanks Fusion

LS 4S · Post by **LS 4S** » Sat Sep 18, 2021 7:20 pm

Many thanks for your input and time So reds positive i can connect to that what do I connect neutral to

Fusion · Post by **Fusion** » Sat Sep 18, 2021 11:07 pm

The thick red wire connects to the battery +ve terminal. The thick black wire connects to the battery -ve terminal.
I'm getting the feeling that electrical/electronic stuff is not your strong point ... please be cautious, don't destroy your new machine before you've had the chance to use it.

LS 4S · Post by **LS 4S** » Sun Sep 19, 2021 7:07 am

do you mean this

LS 4S · Post by **LS 4S** » Sun Sep 19, 2021 9:59 am

i had intended to use this

LS 4S · Post by **LS 4S** » Sun Sep 19, 2021 11:00 am

and this

Fusion · Post by **Fusion** » Sun Sep 19, 2021 11:27 am

"do you mean this?"
Definitely not.

The thick wires I'm talking about are the two that solder onto the PCB.
More info/pics of what you have/haven't got are needed.
So ...
Do you have the coiled cable that links the battery-box to the control-box?
Do you have the battery-box?
The one photo you posted - is that cable inside the battery-box?

LS 4S · Post by **LS 4S** » Sun Sep 19, 2021 12:08 pm

i don't have the battery box all i have is the lead

Fusion · Post by **Fusion** » Sun Sep 19, 2021 1:36 pm

I understand better now.
Someone been hacking about, so you can't trust their work, or their choice of wire colours, or their uninsulated solder joints etc.
What's underneath the sticky tape would be useful to know. The cable may just have two orange wires ( audio ) and two black wires, for power. The only way to be certain which is which is to trace the wires all the way to the circuit-board inside the control box. An electricians multi-meter would make this easy, you could perform a 'beep' continuity test from the PCB to the mystery curly cable wire ends to find out which is +ve and -ve. You could also test out that thermal trip to see if it's a short-circuit.
A proper in-line headphone socket would be a sensible idea when you're tidying things up, perhaps get a headphone extension cable and chop off the socket leaving 20cm of cable to join up to the orange wires.

LS 4S · Post by **LS 4S** » Thu Sep 23, 2021 1:39 pm

I powered the unit up 3 times using the wiring config in the picture the first time seemed ok the second time got audio but the coil didn't seem to be working the third time nothing have I blown a fuse or something

LS 4S · Post by **LS 4S** » Thu Sep 23, 2021 2:29 pm

is this battery ok

Sirbleepsalot · Post by **Sirbleepsalot** » Thu Sep 23, 2021 3:32 pm

Hi, aside from your obvious problems already identified I would refrain from using anything described as a "Super rechargeable Li-ino (?) battery". If the supplier can't get that bit right...

You are at the point where unless you have, and know how to use, a bench power supply, multimeter and ability to read circuit diagrams you should quit while you're ahead.

Believe me, I have been there and learned the hard way.

Regards, Dava.

LS 4S · Post by **LS 4S** » Thu Sep 23, 2021 5:56 pm

update there's still power going to everything seems like a loose connection because when I shake the control box I get audio over the head phones

Metal Detecting