Search Scan Electronics 650 Rtr
By Andy Sabisch
From Page 18
June, 1993 issue of Lost Treasure
Search Scan Electronics is one of the newest metal detector manufacturers, having been in business for just under two years. Since their inception however, they have developed and produced several innovative treasure-hunting products. These include a set of high-quality headphones called the Optiphones and two waterproof metal detectors with above-average performance.
Having used the VLF 450 with considerable success in several parts of the country over the last few months, I was anxious to try their newest model, the 650 RTR.
The 650 RTR or Rapid Target Response utilizes a pulse-type circuit for target detection. Pulse technology was developed nearly 20 years ago in an effort to enable metal detectors to locate deeply-buried metal objects in areas containing high concentrations of mineralized soil or salt water. These conditions adversely affected the ability of other types of metal detectors such as TRs, BFOs, and even VLFs to locate deep objects, and as a result, many objects remained after an area had been searched.
Search Scans lead engineer, Joe Cooper, recognized the benefit of pulse technology; however, he felt that there were two major drawbacks that needed to be addressed. First, the sweep speed of most pulse detectors was quite slow which limited the size of the area that could be searched in a given period of time. Secondly, pulse detectors by design respond to all metal targets. In the past the only way to discriminate out unwanted targets was to use a technique called pulse delay. While this did allow targets such as tin foil and pull tabs to be rejected, a significant loss of detection depth occurred with ferrous targets such as nails still being detected. Search Scan developed several innovative changes to the traditional pulse circuit which are reflected in the 650 RTR.
The most noticeable improvement is in the sweep speed. The search coil can be swept at speeds ranging from almost no motion to competition-hunt speed with no loss of target detection capability. This enhancement will allow both land and water hunters to cover more ground in a shorter period of time resulting in a greater number of targets being recovered.
The second design feature incorporated into the 650 RTR is audio target discrimination. Rather than using pulse delay circuitry to reject unwanted targets, the 650 will produce a different type of signal as the search coil passes over either ferrous or non-ferrous targets. This allows the USER instead of the DETECTOR to reject unwanted targets allowing maximum detection depth to be achieved at all times. Another noticeable improvement is the lack of the oscillating or clicking threshold common to most other pulse detectors. The 650 features a steady threshold similar to that found on a VLF circuit.
Search Scans design philosophy has been one of producing high quality products at affordable prices that are simple enough so that anyone can use them.
The 650 RTR was obviously designed with this in mind. There are two knobs on the front of the control housing which control the detectors operation. The knob on the right hand side of the panel labeled SENSITIVITY performs two functions. It turns the detector on and regulates the signal strength emitted from the search coil. The knob adjacent to the SENSITIVITY control is used to adjust the volume of the audio signal heard through the high-quality waterproof headphones which are hard-wired into the control housing. A feature of the headphones that indicates Search Scan has thought about the end-user of their products is the ability to replace the padded cushions in the event they become damaged or dirty.
The control housing measures only 3.5 inches wide by 8 inches deep by 1 inch thick. Constructed of high-density ABS plastic, it is ultra-sonically-welded to ensure the detector remains leak proof throughout its lifetime. The 650 RTR can be submerged up to 75 feet which is sufficient for virtually any type of treasure-diving activity due to the limitations on bottom time that result from going deeper.
The 650 RTR comes equipped with an 8-inch resin-filled, low profile search coil. The cable which connects the search coil to the control housing was selected after considerable research into problems experienced by professional underwater salvage divers throughout the world. It features a heavy-duty braided Teflon layer to prevent leakage caused by cuts from sand or coral as well as internal breakage of the individual wires.
Since the 650 RTR features interchangeable search coils, there is a waterproof connector on the cable which connects to the bottom of the control housing. The standard 8-inch coil is more than sufficient for general treasure hunting; however, a 10-inch and 12-inch coil is available if needed. The 10-inch search coil will provide about 15% more depth than the 8-inch coil and the 12-inch coil will add approximately 10% to the increase obtained from the 10-inch coil. While the larger coils will detect deeper and cover more area with each pass, pinpointing becomes more difficult and there is a slight loss of sensitivity to smaller targets.
The 650 RTR is powered by three 9-volt batteries which are located in a separate compartment at the front of the control housing. The batteries simply snap in place thereby eliminating both battery leads and plastic holders which frequently break, possibly rendering the detector inoperable. This is another feature which shows that Search Scan has attempted to build a detector that spends its time in the field finding targets rather than on a work bench being repaired.
The posts that connect the batteries to the circuit board are sealed to prevent any leakage from one compartment to the other. The factory recommends that only alkaline batteries be used. Circuit design improvements have resulted in battery life of 20 to 30 hours with a built-in low battery alert signaling the user when they require replacement.
A few days after receiving the 650 RTR, my family and I went to visit my wifes relatives who live in Charleston, South Carolina. We asked them about the various beaches in the area and they recommended that we try Kiawah Island which is an extremely popular summer-resort area.
Despite being the beginning of February, the weather was picture-perfect as we arrived at the beach with the temperature in the mid-S Os. As I surveyed the vast expanse of sand, I wondered how much there would be to find since the beach had not been used in the six months since Labor Day. You could also be sure that I wasnt the first treasure hunter to search the area.
With a positive outlook, I set the volume at 75%, adjusted the SENSITIVITY control until a faint threshold signal was heard through the headphones and began hunting the dry sand near the edge of the dunes. A few minutes passed before I received the first signal it was faint but distinguishable. Using a long-handled scoop, I removed 5 or 6 inches of sand and rechecked the area.
The signal was still in the hole so I continued digging. Finally, at almost 10 inches, I saw a green disk sticking out of the side of the hole. Once I pulled it free and rubbed some of the corrosion from the surface I could tell it was a copper penny that had obviously been there for some time.
As I walked towards the ocean I noticed that the damp sand contained a high concentration of mineralized black sand which greatly limits the depth most detectors can locate targets.
Anxious to see how the 650 RTR responded to these adverse conditions, I was pleased when I began receiving signals with amazing regularity. After 45 minutes, my wife came over to show me some of the shells she and my son had found along the beach and asked howl was doing. Emptying out my pouch we were both surprised to see that I had 23 coins and two door keys not bad for a beach that had not really been used for several months.
As Rosanne watched, I continued searching along the edge of the surf. After only a few sweeps I received another clear signal. Removing several scoops of wet sand from the hole the detector indicated that the target was finally out. Moving the sand around I recovered a large hotel room key both of us were stunned to see the depth at which it had been buried nearly 18 inches!
As both the sun and the temperature dropped I made one more pass towards the surf line before heading back to the car. Looking over my finds back at the apartment, I began looking forward to continuing my search the next day.
Arriving at the beach around 8 A.M., the temperature was noticeably cooler than it had been the day before. Almost immediately I began finding coins near where I had left off the day before. I had been hunting for about an hour when another treasure hunter walked over the boardwalk and headed towards me. He introduced himself saying that he lived nearby and hunted the beach on a regular basis along with several other local hunters. We compared detectors, and he appeared skeptical that I had found the number of coins I had in my pouch in such a short period of time. In order to compare the performance of the two detectors, I told him I would mark several signals in the wet sand, then we would re-check them with his detector.
Over the next 30 minutes I marked 20 targets along the waters edge. Dave then checked each signal, and even by reducing the discrimination level on his detector to 0, he was only able to detect six of the 20 targets. Carefully recovering each one, we found that every signal was a coin ranging from 6 to 14 inches in depth. Three of the shallower coins were sticking straight up and down between 6 and 8 inches deep in the marbled black sand. Dave said Im going to see the local dealer in Charleston and see if he can order me one of these detectors so that I can rework the beach and find what weve been passing up. Healso said he was looking forward to using it during the summer when coins and jewelry were continually being replenished.
One of the more interesting items I found on the beach was a disk the size of a quarter with Schoedinger Crematory, Columbus, Ohio stamped on it. As I held it in my hand I began to wonder how it wound up on this stretch of beach on the South Carolina coast.
It was impressive to note that the 650 RTR did not require ANY adjustments as I walked back and forth from the dry sand through the damp black sand and into the surf washing up on the beach. As a matter of fact, the only time I had to touch the controls during several hours of searching was when I turned the detector off at the end of the day.
During the two days I spent on Kiawah Beach, I recovered an impressive 164 coins as well as several keys and other interesting items. Considering many of the targets had come from depths in excess of 10 inches or had been on edge, the overall sensitivity and performance of the 650 RTR was readily apparent. In addition, after a short period of listening to the signals produced by different types of targets, I was able to avoid digging nearly all ferrous trash targets while still recovering the deeply buried coins others had missed.
Upon returning home, I called Jim Harrick, a long-time friend and experienced treasure hunter, to tell him about the success I had using the 650 RTR in Charleston. Jim operates Hide-and-Seek Detectors in Mullica Hill, NJ and as a result, has tried most of the detectors currently available in his searches. Despite being slightly skeptical, he said that he knew of several lakes which had been heavily worked over the last few years that would be a good test of the RTRs detection depth.
After testing the 650 in his test garden, Jim took it to a lake in northern New Jersey near the New York border which had a small public beach at one end. A number of treasure hunters have worked this site extensively since the mid-1980s and while many pieces of jewelry and hundreds of coins had been taken out over the years, signals were now few and far between. Arriving at the lake, Jim was surprised to find the lake covered with a thin layer of ice. Getting into his dry suit, he used his scoop to clear a small area to hunt.
Adjusting the SENSITIVITY control until the threshold was just audible, Jim began searching in knee-deep water. Almost immediately he received a signal; however, after removing the first scoop he saw a large rusty bolt resting in the float. Realizing that he needed to listen to the signals before digging each one he continued walking towards the edge of the swimming area. Passing up several targets that produced either wide, washed-out signals or a double-beep indicating some type of ferrous object, Jim finally picked up a sharp, clear signal. After removing four scoops of sand from the bottom, the 650 RTR indicated that the target was out of the hole. Dumping the sand into the float, a silver 1952 Roosevelt dime came into view as the sand fell through the screening.
Despite the 33 degree water temperature and a 15-MPH wind blowing across the lake, he began hunting again filled with renewed enthusiasm. By listening for the signals produced by non-ferrous targets, Jim said he was able to recover several more coins and a small religious medal over the next hour at depths ranging from a few inches to well over a foot. He said that most of the targets were recovered deeper then any he had found there in the past. The audio discrimination capabilities of the 650 RTR had worked quite well since other than two deeply-buried nails and a rusted nut, no ferrous trash had been recovered.
Jim called me later that day, and after he finished complaining about how cold the water had been, he spent nearly 15 minutes talking about how well the 650 had performed. He said that as he was heading out of the water he continued sweeping the searchcoil along the bottom and that there were signals throughout the entire area. He found it hard to believe that this was the same beach that he had considered cleaned-out just a few months earlier. He said he was looking forward to rehunting many of his favorite beaches to see what they might still hold.
My job provides me the opportunity to travel extensively and I was pleasantly surprised to find out I was being sent to Rio de Janeiro, Brazil for two weeks. Seeing pictures of the snow white beaches packed with tourists from around the world I was looking forward to some excellent treasure hunting opportunities in the evenings after work.
Unfortunately the deadline for this field test came up before I left on the trip so I wasnt able to include the results of my trip in this article. Hopefully I will be able to pass along the results in another article in an upcoming issue of Lost Treasure.
I found the 650 RTR to be extremely stable, even when searching over rapidly changing ground conditions. Once the sensitivity and volume levels were set, no further adjustments were needed throughout the day. Based on the depth at which both Jim and I recovered targets, the 650 appears to have as much sensitivity as any treasure hunter might need. With the use of the optional search coils, treasure hunters may even be forced to bring someone along to help with the digging due to the extreme depth they provide. The unit is very lightweight and as a result, can be used comfortably for extended periods of time.
While the 650 RTR was designed primarily for beach and water hunting, it can be used successfully for coin and relic hunting as well. Sites with adverse ground conditions or where targets may be deeply buried are ideally suited for this detectors deep-seeking capabilities.
The 650 RTR lists for $599.95 and comes with a standard 8-inch search coil, plus a one-year parts and labor warranty. The 10-inch search coil sells for $119.95 and the 12-inch is $129.95. Coil covers are available for all three coils ranging in price from $7.00 to $12.00. Since the 650 can be used by divers at depths of up to 75 feet, Search Scan offers a shortened upper and lower assembly which is the ideal length for divers. A break-down upper assembly is also available to allow the detector to be packed into a standard size suitcase when traveling.
For more information on the 650 RTR or any of Search Scans other products call them at (205)928-9040 or write them at P. 0. Box 152, Fairhope, AL 36533 be sure to mention that you read about their new detector in Lost Treasure.