GTA 350 adjustments

[tatumj]

Does anyone know what the two scredriver adjustable pots on the 350 do? These are accessable on the back via two plugged holes.

I have a 350 which chatters constantly like is is sending morse code. Anyone encounter this problem?

 

[brrttpaul]

tatum i have two of those on the underside of my gti i dont know what they are either

 

[ohio fred]

I don't know about Garrett's but some you can adjust the ground balance through screw hole that might solve your problem but i don't know the 350.Ask john Edmonton or uncle Willy.

 

[tatumj]

They are not mentioned in the owner's manual. I have built homebrew detectors but I don't intend to touch these until I know for sure what they are for.

I put the coil from my GTP1350 on this machine and it works fine with no chatter.Must be something wrong with the connector or wire going to the coil.

I asked about the adjustments just thinking there may be some adjustment that would have an effect on the chattering problem.

 

[tatumj]

I was thinking it they may be for ground adjustment. I have similar adjustments on a couple of old copies of the Tesoro Silver Sabre I built many years ago.

The chatter, however, is there regardless the position or placement of the coil. Not a matter of ground. I live in South Georgia and the ground minerals here are of little consequence anyway.

 

[Uncle Willy]

You may have a bad coil. The 350's have been around for awhile and are a little long in the tooth. Those holes are plugged for a reason. Contact Mary Penson at Garrett - maryp@garrett .com

They might give you a new coil.

Bill

 

[tatumj]

Bill,
Thanks for the reply. I bought this 350 at a flea market and the problem showed up shortly after. It is somewhat intermittent. It seems to be in the connector as when I wiggle it there is a change but it does not stop.

If the coil itself proves out to be defective, I will open it up. I am interested to know why I get such high resistance readings between the receive coil pins. I would think this the problem except the coil that goes with my 1350 gives similar ohmmeter readings.

I am a pastor now but have several years experience as an electronics technician. Worked as R&D engineering tech at Scientific Atlanta for several years. It is a shame that the detector folks are so secretive with the tech info on their machines. I had to reverse engineer the old Silver Sabre to get a schematic to build from fifteen years ago. I won't go to that much trouble just to discover the function of the two pots in the 350.

 

[Uncle Willy]

Yeah I ownwd a few Silver Sabres. Just buzz Mary and ask her what the two plugs are for and if you can play with them. She will be happy to tell you anything. Great gal to deal with. I owned a 350 about 137 years ago but can't remember much about it. You could have a bad connector or bad connection where it's wired. Bad coils will do all kinds of screwy things. Have you checked it for hair line cracks? If they get water or moisture in them they go nuts.

Bill

 

[tatumj]

I think the Silver Sabre was one of the first Tesoro made. I made two copies but was able to get better sensitivity out of them than the factory made ones. Using one of those old super audio amps they used to sell (may still do) I dug wheat pennies as deep as with any detector I ever tried. That includes the most sensitive detector I have owned, the Fisher 1266X.

I have always tended to want to build and make things. From leather work and making telescopes when in grammar school till now. I just turned 65 and last year made my first violin.

I will contact Mary about the 350 as you suggest. I don't see any crack in the coil housing. I has only a few scratches.It was already old when I bought it at a flea market but when working it does quite a good job on coins.

The church where I am the pastor was organized in 1921. I have dug over 3 pounds of clad coins and a few silver out of our grounds. They just keep coming. Most now from 4 inches plus.

 

[Uncle Willy]

Even a hair line crack will give you fits. Sounds like you have a goldmine at your church. Good luck.

Bill