Compass Coin Scanner Jr.
By Andy Sabisch
From Page 8
June, 1991 issue of Lost Treasure
The newest member of the engineering staff at Compass Electronics is George Payne who over the years has been responsible for the design of the ground-balance circuit, the motion-discriminate circuit, and both the target identification and coin depth-reading circuits.
Shortly after joining Compass, George began to design two new models incorporating the features that most treasure hunters wanted. The result of his efforts are the Coin Scanner Pro and Coin Scanner Jr. which were introduced in the middle of 1990. Having used various Compass detectors and other models designed by George with a great deal of success in the past, I was looking forward to testing the new Coin Scanner Jr.
The Coin Scanner Jr. is a silent search discriminator with automatic ground balance and a non-motion ALL-METAL pinpoint mode. It also features notch discrimination and audio target identification.
As with the other Scanner models in the Compass line, the Coin Scanner Jr. is mounted on a modified S -shape rod, and at three- and-a-half pounds is both extremely lightweight and well balanced. The control housing slides easily from the rod for hip mounting and the bracket then doubles as a belt loop. The searchcoil comes with seven feet of cable which eliminates the need for an extension cable and allows the Coin Scanner Jr. to be used in shallow water without fear of damaging the electronics or the coil.
The controls on the Coin Scanner Jr. are two knobs-POWER LEVEL and TRASH OUT; a toggle switch TARGET TONE; two touchpads TRASH OUT and PINPOINT; and an indicator light. There are PRESET marks on the two knobs which allow even a beginner to set the controls to the optimum position for normal searching.
The TARGET TONE toggle switch selects one of three audio response modes to provide the user with information on the target in a manner similar to a target ID meter.
When set in the far right position, a single tone will be produced for any target that falls above the discriminate level set by the TRASH OUT knob. When placed in the far left or DUAL position, a medium pitch tone will be produced for targets that fall above the discriminate level set and below copper pennies which includes nickels, gold rings, pull tabs, screw caps, and zinc pennies. Targets that fall above this point will produce a high-pitched tone.
With the toggle switch in the center or TRI position, a low tone will be produced by targets that fall above the discriminate setting and below pull tabs. Nickels and small gold rings are included in this area. Pull tabs, screw caps, zinc pennies and some gold objects produce a medium tone; with other coins and silver jewelry producing a high-pitched tone. After a little practice on known targets, this tone identification system can be as effective as a target ID meter in selecting which targets to dig.
Another feature of the Coin Scanner Jr. is the AUTO NOTCH discriminate setting. By turning the TRASH OUT knob my counterclockwise, the auto notch circuit is activated. In this mode, the detector will reject tin foil, nails, and other small pieces of iron, as well as pull tabs and screw caps while still responding to nickels, some gold items, and other coins that normally register on the high end of the scale. The TARGET TONE toggle switch will work in this mode as well, and will produce a medium/high tone when placed in the DUAL position or a low/high tone when placed in the TRI position.
The indicator light located in the upper left comer of the face provides two functions. When the Coin Scanner Jr. is first turned on, the relative battery strength is indicated by the length of time the light remains on. New batteries will keep the light on for approximately four seconds, and the batteries should be replaced when the indicator comes on for one second or less. The second function is to provide an indication when the searchcoil passes over a target. When operating in the PINPOINT (all metal) mode, the light is extremely useful in pinpointing the target in conjunction with the audio response.
There is a standard 1/4-inch headphone jack located on the rear of the control housing. Due to the location of the jack, it is best if your headphones have a 90 degree plug rather than the standard straight plug in order to avoid breaking the wires inside the headphone cable. If you are unable to find a set of headphones with this type of plug at your local dealer, you can purchase one at any electronics store and replace it yourself.
Another improvement that George Payne has incorporated into the design of the Coin Scanner Jr. is in the type of batteries used. Rather than the three 9-volt batteries used in the other Scanner models, both the Coin Scanner Jr. and Pro use 8 AA penlight batteries. This change, combined with the new surface mount circuit design, provides for 40 to 50 hours of hunting on a set of standard carbon batteries. Alkaline batteries will provide approximately 10 hours more, and rechargeable batteries can be used with no loss of performance.
After assembling the Coin Scanner Jr. and reading over the instruction manual, I performed an air test to see how the detector responded to various targets. Setting both the POWER LEVEL (sensitivity) and TRASH OUT (discriminate) controls to the PRESET marks, I proceeded to pass various targets such as coins, jewelry, and small artifacts past the loop.
The detector produced solid signals at fairly impressive distances from the coil. Next I selected the AUTO NOTCH mode and repeated the test. There was no loss in sensitivity to most of the targets; however, all the gold items except for a small 14KT child's ring were rejected. It is important to remember that, when using the notch discriminate mode, most gold objects, zinc pennies, and Indian head pennies will be rejected along with the pull tabs and screw caps.
After completing the air test, I proceeded to see how the Coin Scanner Jr. performed in my test garden. I turned the POWER LEVEL control to maximum, and set the TRASH OUT control to preset. As I began to sweep the coil over the ground, some chattering occurred due to the high ground mineralization, so I reduced the sensitivity to just below the preset mark and the falsing stopped.
The coins and relics that ranged from 3- to 5-inches deep produced clear, repeatable signals; however, the silver quarter at 6 1/2-inches produced an intermittent broken signal and a.58 caliber minnie ball at 7 inches and a silver half at 8 inches did not produce any response.
I continued to search as I headed back to the house, and found that the Coin Scanner Jr., with the TRASH OUT set at preset, did not produce any response when passing over the nails I knew were present from the construction of the house.
Shortly after receiving the Coin Scanner Jr., a project came up that required me to be out of town for a period of time, so I had a friend of mine, Don Elkins, assist me in field testing the detector. Don is interested in treasure hunting but has only used a detector once or twice before and I thought he would be able to provide some valuable feedback on its performance in the hands of a novice.
The first place he took the Coin Scanner Jr. to was Myrtle Beach on the South Carolina shore for a family vacation. After spending part of the first day scouting out likely looking spots to search, he took his two daughters down to an area where a Volleyball game had been played earlier.
Setting the POWER LEVEL to maximum, the TONE TOGGLE switch to the TRI position and the TRASH OUT control to preset in order to avoid rejecting any jewelry items, Don started to search near the net.
Almost immediately he received a high-pitched tone and, after digging several inches down in the damp sand, found a well corroded quarter. As he continued to search, his daughters took turns digging the targets he located.
After 45 minutes, Don received a low-tone signal and just under the surface they found a gold chain and small crucifix which unfortunately turned out to be gold plated. Despite the fact that the find was not worth much, his daughters appropriated it and acted as if they had found Blackbeard's treasure. As the sun began to set, Don headed back to the campsite with slightly more than $ 10 in change, several keys, a dog license, the chain, and a few pull tabs.
The next day Don searched in front of the larger hotels located on the beach. Despite signs requesting that cans and bottles be kept off the beach, he quickly became frustrated after finding 30 or 40 pull tabs and screw caps. Turning the TRASH OUT control counterclockwise to activate the AUTO NOTCH circuitry, Don continued to search around the lounge chairs on the beach.
While he did reduce the likelihood of locating jewelry items, he was able to ignore nearly all the trash present. Don said that by combining the audio target identification with the AUTO NOTCH mode, he was able to tell if the target was a nickel, key or other denomination coin before he recovered it. After a few hours of searching along the beach, he headed back with a sunburned neck and a pocket full of coins but, most importantly, very little trash.
The next area that Don took the Coin Scanner Jr. to was an older residential area in downtown Chattanooga, Tennessee. Don lives in Chattanooga and knows many of the property owners in that section of town. After getting permission to search one of the larger yards on the block, he set POWER LEVEL and TRASH OUT to preset, the TONE TOGGLE to the TRI position, and began to search.
After several sweeps, he received a high-pitched tone near the path leading to the front door. Pressing the PINPOINT touchpad, he centered the target under the loop using the audio response as well as the signal-indicating light. Careful probing produced a 1917 wheat cent from a depth of 4 inches.
Continuing around the side of the house, Don received a medium- pitched tone near a large tree. Expecting to find a pull tab or screw cap, he cut a shallow plug and rechecked the hole. The target was still deeper, so he began to remove some of the dirt from the bottom of the hole. At a little over 5 inches, Don saw something white and carefully pulled an unfired .69 caliber minnie ball from where it had lain for the last 126 years.
After an hour or so, Don headed back to the car with several wheat cents, some modem coins, a house key, and the minnie ball-a successful hunt for a newcomer to the hobby of treasure hunting.
When I returned home, Don brought the Coin Scanner Jr. over and promptly purchased one for himself-he had become a treasure hunter. I had a few spots where I wanted to try the detector and the first was a nearby elementary school where someone was swinging a detector nearly every time I drove by. The highly mineralized ground, combined with cinders from the furnace that had been spread on the ground over the years, would test the Coin Scanner Jr.'s ground-canceling capabilities.
Upon arriving, I headed to the older playground and ball field, set the TRASH OUT and POWER LEVEL to preset and the TONE TOGGLE switch to the TRI position. As I began to sweep across the playground, I received a number of false signals caused by the ground conditions. I was forced to lower the POWER LEVEL control to the "4" position in order to reduce the ground effect.
After digging a number of pull tabs, I began to ignore those signals that produced a consistent medium tone. On several occasions I received a signal that produced a high tone in one direction and then a medium tone on the next pass. I found that in all cases the target was a zinc penny that was "reading" right at the point where these two audio discriminate settings were set. A few hours of searching produced a handful of coins, all new; however, by using the audio target identification feature, I had dug virtually no trash.
The next site I went to was a construction site near the foot of Kennesaw Mountain. I had heard that some Civil War relics had come out of this area, and I hoped to find a few relics myself. Setting the POWER LEVEL to preset and the TRASH OUT control to just above NAILS (in order to avoid missing any small iron relics such as gun parts or shell fragments), and the TONE TOGGLE to TRI, I began to search near the tree line.
The first 2 targets produced high pitch signals and resulted in 12-gauge shotgun shell casings at 2 to 3 inches. The next signal was intermittent, so I kicked an inch or two of loose dirt out of the way and rechecked the area. This time the signal was clear and repeatable. At slightly over six inches, I found a fired .58 caliber minnie ball that had obviously struck something before coming to rest in the red clay. The next few signals also produced fired minnie balls of various calibers at depths of 3 to 6 inches.
On the way back to the truck I received a low-pitched tone and used my mattock to recover it. At eight inches, I found a rusted piece of iron, which at first appeared to be worthless; however, after knocking the loose dirt from it, I saw that it was a shell fragment, probably from a Hotchkiss shell. The audio target identification worked well in this application as I could tell, before digging, if the target was iron (low tone), a minnie ball or button (medium tone), or a coin or shotgun shell (high tone) with a great deal of accuracy.
The Coin Scanner Jr. is extremely easy to operate and even a beginner is able to locate coins and other valuable targets while ignoring most trash items normally encountered. The audio target identification system is nearly as effective as a target ID meter and, with a little practice, allows the user to identify most targets reducing the amount of unnecessary digging.
The Coin Scanner Jr. does require reducing the sensitivity when searching over highly mineralized ground in order to reduce falsing; however, the factory told me that their dealers have been instructed in how to make an internal adjustment to compensate for this. If the area you live in is highly mineralized, you should ask your local dealer to make this adjustment to enhance the performance of the detector.
The Coin Scanner Jr. retails for $399.95, and offers many features not seen on detectors in this price range. If you are in the market for a new detector that is both simple to use and includes features such as notch discrimination and audio target ID, you should look at this new addition to the Compass line before you buy.
For more information on this and other models available from Compass as well as the name of your nearest dealer, write the factory at Compass Electronics, 3700 24th Ave., Forest Grove, OR 97116, or call them at (503) 357-2111 and mention that you read about it in Lost Treasure.
Andy Sabisch frequently conducts field tests for Lost Treasure.