Hello All! New To This Forum Not Metal Detecting. Need Some Assistance With Jetco Mustang

[cowtownkid]

Yes, what away for an introduction...Jetco Mustang, Jeeze.

I started metal detecting in 1971 when my dad finally gave in and bought me a Jetco Treasure Hawk for my 11th Birthday. I actually wore small holes in the bottom of the coil.

I was hooked. Traded to a Garrett TR in 1973-74 & kept upgrading. I actually made a career using metal detectors, partially anyway, working for the City of Fort Worth Water Dept. for 31yrs. 17yrs. as a Supervisor. I first learned how to use the Gemini II back in early 80's. Tracing lines inductively/conductively & also using as a two box unit locating MH's & water valves etc.

I actually located an old 24" cast iron main laid in the 1920's near downtown with a backhoe standing by...The main was a bit over 14' deep. It took a while, but I had it dead on.

Anyhoo...enough of that, I was given an old Jetco Mustang in 1991 & it has been hanging in my garage ever since, never paid much attention to it until recently. I put a new 9V battery in & it actually works! However the tuner needs a good cleaning. I completely broke down the old unit except for the circuit board. The single knob on the Mustang secures board to upper housing & I got the nut loose with no issues, however, I cannot get the black plastic knob off the plastic spline? No set screw is visible & I have cleaned & lubed the spline area. I am wondering if there is a set screw under the top decal of the knob? I just don't won't to damage or mar this old vintage unit.

Any help would surely be appreciated.

I have read Steve's articles & reviews over the years & they are absolutely informative & helpful.

Thanks to all!

cowtownkid  

[2Valen]

1 hour ago, cowtownkid said:

No set screw is visible & I have cleaned & lubed the spline area. I am wondering if there is a set screw under the top decal of the knob?

Welcome to the forum, and to answer your question I have never seen a screw on top of a knob before. Should there be a screw on the knob it would be close to the bottom of the knob, either a small Allen or a flat head screw would show up.

Some of the older knobs were just tight and hard to remove. Just pull straight and evenly and it should come off.

Don't pry it up because it will break due to it's age.

Others on this forum may have a better answer than I do as they have been around more detectors than I have.

 

[GB_Amateur]

10 hours ago, cowtownkid said:

I am wondering if there is a set screw under the top decal of the knob?

Welcome, cowtownkid!  To answer your question -- I do recall seeing such, that is an attachment method hidden by a decorative cover/cap/recessed disc on the top of a knob.  If you remove it carefully (I'm W.A. guessing it's aluminum) you should be able to replace it later.

10 hours ago, cowtownkid said:

Tracing lines inductively/conductively & also using as a two box unit locating MH's & water valves etc.

I actually located an old 24" cast iron main laid in the 1920's near downtown with a backhoe standing by...The main was a bit over 14' deep. It took a while, but I had it dead on.

You found a 24 inch diameter pipe that was buried 14 feet deep with a 2-box metal detector operated from the surface of the ground??

 

[cowtownkid]

That is kinda what I have been thinking...This dang thing is just to tight for what it is...

& it looks like the screw could very well be under that thin decal...

Appreciate the info!

[Geotech]

On my Treasure Hawk the knobs just pull off.

[cowtownkid]

On the depth & location of water main...I sure did.

I was one of the oldest mains that size still in service. Left the Holly treatment plant and meandered to the Northside. It cut across a large church/private school property.

I started at an Arial crossing (on piers) about 500 ft. away. At this point with pipe exposed, I set the Transmitter part of box on top of the main. I just traced towards the property, however, the lot had been filled in over the years. At the point of excavation, I just barely got the box far enough away to avoid any interference between the two units, using sensitivity adjustments & raising Receiver box 3 ft. or so off the ground. I believe it was 14.4 ft. deep from Top of Ground. Surveyors came out & GPS'd it.

Anyway, school & church was demolished & a shining new 20 story Pier 1 Imports Headquarters  was built. Pier One declared Bankruptcy a year later...Go Figure

cowtownkid

[BeachHunter]

Welcome to the forum CTK. Best of luck on the vintage equipment and good luck detecting.

[dogodog]

Glad to have you aboard!!! as for the knob thing if its aluminum on aluminum it might be a corrosion problem. If it's plastic it very well could be just a tight fit. in any case don't rush the process. And please post some photos of the machine. Would love to see it

[cowtownkid]

Thanks all of the advice & suggestions...I just got in & will post if I eventually get this newsome off.

If so, I'll post a few pics as well.

cowtownkid

[Tom_in_CA]

Welcome from coastal CA .   The Garrets of the mid 1970s were among the best of that era.  Wasn't till the later 1970s that Whites pushed them off that throne.