Garrett Groundhog ADS Schematic

I don't think there is any electronics within the coil housing.

If so it would only be a Cap and Resistor.




Linkback:

You are not allowed to view links.
Please Register or Login

http://www.thunting.com/smf/index.php/topic,7050.msg45699.html#msg45699

ARRRGH!;

You guys have been kicking around that poor lil resistor, in the coil, and have not figure out yet what it is there for! Should I tell you when GoldDigger1950 has not? I am sure he knows.

Anybody ever take apart a TV deflection coil, for  the wire? Did yo see all those resistors in there?

goldigger.

Linkback:

You are not allowed to view links.
Please Register or Login

http://www.thunting.com/smf/index.php/topic,7050.msg45728.html#msg45728

The resistor forces a rapid collapse of the transmitted pulse so it won't swamp the receiver coil. Timing is obviously critical and if the transmitted field collapses too slowly, the receiver can't see beyond it. Remember that the GroundHog is a VLF/TR machine with ground balance and discrimination. It also has manual tuning and sensitivity adjustments. Inside the coil, the resistor takes the form of a strip of carbon on plastic where the coil wires are laid on the carbon and adjusted that way during assembly. Electronically, that does the job better than a fixed resistor or a potentiometer which can fail, being mechanical and all that. The resistor is in the circuit during the transmit cycle so there is an additional capacitor in the machine itself to boost power during the transmitted pulses. The tuning of the transmit circuit is then complete.

Isn't that fun?

The GroundHog ADS was one of the most complex yet competent machines of its day and still works in almost any condition at all. It's a highly valued asset here in the Australian goldfields. This is the reason I am replacing the wire harness. Remember the wire harness? That was my initial reason for seeking the schematic. I just want to have it on hand if things get too hairy during the process. Brittle wires and all that. I have it all photographed in detail but still want the paper diagram. I'm fussy like that.

Leftfield is looking for the schematic too and in PM we have discussed why. It's no secret but to clarify things I asked him if he needed a spare part and he explained his requirement. He needs a wiring diagram of the coil connector pins rather than the battery as I had assumed from his posts here. Thus, an answer will be forthcoming from me when I break out my spare coils.

Linkback:

You are not allowed to view links.
Please Register or Login

http://www.thunting.com/smf/index.php/topic,7050.msg45737.html#msg45737

He needs to know which two are for TX and which are for RX. If you can determine that for him he should be quite happy.

Linkback:

You are not allowed to view links.
Please Register or Login

http://www.thunting.com/smf/index.php/topic,7050.msg45751.html#msg45751

		Quote:			Posted by leftfield
	Yes - very happy  *waits with baited breath*

LoL!!!!!!!!

Worms on the breath, mate?

Linkback:

You are not allowed to view links.
Please Register or Login

http://www.thunting.com/smf/index.php/topic,7050.msg45906.html#msg45906