Compass 77b pro

[Kevin from Detroit]

Found one of these at a local resale shop. I know this is an old dog, and probably a bit much at $35, but after using motion discriminators all my time in the hobby, just had to live the experiance of learning to use a tr. After cleaning it up, fixing a loose coil rod problem, intermittant wires in the coil connector, & picking up the required batteries and packs from RS, found it does basically work and find metal. Have a user manual from Keith Wills on the way. Major problem, expected after reading forums and such, is tuning stability. Deceided the best use of the meter was to set the tune to basically split the meter straight up and down, ferrous to the left and metal to the right. Soon as the coil is moved a ways though, it quickly goes out of setting, the needle drifting off to left or right, and have to constantly re-adjust it as the coil is moved. Just wondering if anyone has heard of a manual retune button or auto retune circuit that could be added, or if this is just life with the old tr. Of course, I realize I could just be setting it up or using it wrong. Also, all the knob functions are clearly marked, but there is a slide switch on the front of the case near the coil connector that is unmarked. Any Idea what this does?

Thanks,

Kevin

 

[Dan-Pa.]

Not familiar with this oldie but detecting is hard work and oldies but goodies did not go deep and would invest in a newer model unless its just doing some experimenting..Manual should help when it arrives and many buy these oldie but goodies as a conversation piece for their den wall..Several years ago saw a fellow using a 20 year old compass judge and he was doing better than most who were hunting beach...so do have fun...

 

[alaskaseeker]

Heres a good thread about the Compass 77B, a great unit and it will still outperform higher end units in certain instances and it will surprise you..Jump right in and ask questions you will get an asnwer instead of BS...Geo

 

[alaskaseeker]

Heres a good thread about the Compass 77B, a great unit and it will still outperform higher end units in certain instances and it will surprise you..Jump right in and ask questions you will get an asnwer instead of BS...Geo

http://www.adn.com/money/story/6933281p-6832208c.html

 

[alaskaseeker]

Thinking with my rear end again heres the thread..Geo

http://members5.boardhost.com/MetalDetecting/msg/24297.html

 

[Kevin from Detroit]

Thankyou for the excellent info. Great site. As much surfing as I do , surprised I haven't run into it. Well, as far as any mods, guess the best thing to do with this detctor is just wax and polish it up and leave it alone. So far, practicing at the beach, seems to best way to deal with the constantly varying threshold is to hold the detector handle with one hand, move the searchcoil very slowly, very level with the ground, while the other hand is adjusting the fine threshold knob in an effort to keep the meter needle at the split position at all times. Next is to experiment with various trash and good targets, to learn response and masking characteristics. Have a shoebox I take with me to the beach partially full of all manner of junk, old rusted nuts & bolts and nondecript ferrous objects, iron and modern nails, bottle caps, screw caps, all kinds of pull and pop tabs, hot rocks, foil, etc etc etc.