I made a few videos about our trip to Chicken Alaska this year. Here is episode 1:
By Steve Herschbach
All-new patented 8"×12″ Dual Field coil for improved depth and sensitivity. Bonus 7.5″ Dual Field concentric coil for a limited time!
To hunt all day, you need a lightweight detector that still provides high performance. The TDI SL Metal Detector has pulse induction power that provides unbeatable depth and sensitivity and is designed specifically for prospecting and identifying relics.
Special prospecting features make life easier, such full-control ground balance that filters out the iron mineralization of hot rocks, black sand, and other tough grounds.
This compact detector weighs only 3.5 pounds with its waterproof 7.5" x 12” High-Q Search Coil, which offers deep detection depth. Other accessory coils are also available.
The rechargeable NIMH battery lasts up to 6 hours, and a backup AA battery back will power all-day exploration.
Owner's Manual (for TDI SL series, none specific to High-Q)
White's TDI SL High-Q Camo metal detector
White's TDI SL High Q Technical Specifications* Internet Price TDI SL High Q $1099 (available in both tan or camo colors) Technology Ground Balancing Pulse Induction (GBPI) Frequency 3250 - 3370 Pulses Per Second Autotune Mode(s) Slow Motion Ground Rejection Manual, one turn control Soil Adjust Ground Balance On or Off (two position switch) Discrimination Conductivity switch*, 10 - 25 Pulse Delay Volume Control No Threshold Control One turn control Tone Adjust No Audio Boost No Frequency Offset One turn control Pinpoint Mode No Audio Output Speaker, 1/4" headphone socket Hip Mount No Standard Coil(s) 7.5" x 12" High Q plus bonus 7.5" round Dual Field (Limited Time only) Optional Search Coils Over 100 accessory coils available by White's and others Battery Rechargeable NiMH & AA Operating Time Up to 6 hours Weight 3.5 pounds Additional Technology The TDI was designed specifically to be able to use Minelab SD/GP compatible coils. However, performance can vary and the pulse delay may have to be advanced to compensate for coil differences that result in overload readings.
Notes *The TDI is unique in that it can suppress audio responses into two different classes. Targets have a high tone or low tone audio depending on how the target relates to the ground balance setting. In general high conductive targets give a low tone and low conductive targets a high tone. The TDI can be set to allow for one response or the other. See White's TDI Coin Settings for more details on this control. *Notes on Technical Specifications - Detailed notes about the specifications listed in this chart.
White's TDI SL High-Q Tan metal detector
White's 7.5" x 12" High-Q coil for TDI series
White's 7.5" round Dual Field coil for TDI series
By Steve Herschbach
This gold prospecting and metal detecting story takes us all the way back to the beginning - my beginning that is. I was fortunate enough to be born in the Territory of Alaska in 1957. Alaska was still very much on the frontier back in those days. My father was a farm boy from the midwest who headed for Alaska in the early 50's with not much more than an old pickup truck. He worked as a longshoreman offloading ships in Seward, Alaska for a time. He decided to get some education and earned his way through college in Fairbanks, Alaska by driving steampipe for the fleet of gold dredges that were still working there. He spent some time in Seldovia, Alaska working the "slime line" in a fish cannery. He met my mom in Seldovia, the two got married, and finally settled in Anchorage, Alaska.
I came along in 1957. My father had taken a job as a surveyor but money was tight in the early years. I was raised on wild game and garden grown vegetables, and as soon as I was old enough to handle it, I was walking a trapline every winter with my father. Dad was a hard worker however, and Alaska was having one of its many booms at the time - the construction of the oil and gas fields in Lower Cook Inlet. This was the Swanson River oilfield, discovered the year I was born.
The state was prospering and my father along with it as a surveyor on the new Swanson Field. He got the bug for flying early on, and by the time I became a teenager he finally got his dream plane at the time - a Piper Super Cub, the classic Alaska Bush airplane. Super Cubs equipped with oversize "tundra tires" can land just about anywhere you can find about 300 - 400 feet of open ground. A great little airplane and the one I ended up flying to get my own pilot's license.
Super Cub N1769P parked on knoll in Talkeetna Mountains, Alaska
It was in this same timeframe that dad got me hooked on gold prospecting. In 1972 I saw an ad in a magazine "Find Lost Treasure" and had acquired my first metal detector, a White's Coinmaster 4. This must have got discussions going about gold, and my father did have some knowledge on the subject having worked around the gold mines in Fairbanks. He took me to a little creek south of Anchorage, Bertha Creek, and I found my very first flakes of gold! By the ripe old age of 14 gold fever was in the air, I had my first metal detector, and already wanted a gold dredge. My first dredge, a 3" Keene with no floatation, was on the way to me in 1973.
Keep in mind that the price of gold had only recently been deregulated from the old fixed price of $35 per ounce. In 1972 it was around $60 per ounce, and in 1973 made it to just over $100 per ounce. The money was not my motivation at all. I already just loved finding gold, and the connection to the prospectors of old and the historical quest for gold were more compelling than any dream of striking it rich. I just wanted to find gold!
My first metal detector and first gold dredge (my 3502 had the older aluminum header box & a power jet)
A young man with a new detector, new gold dredge, gold fever, and a father willing to fly him anywhere in Alaska on adventure. How great is that? Now there was only one problem - where to go? There was no internet then, so it boiled down to libraries and research. In short order I discovered the United States Geological Survey (U.S.G.S.) bulletin series and the number one Alaska title of the series, Placer Deposits of Alaska, U.S.G.S. Bulletin 1374 by Edward H. Cobb. This one book and the references contained in it became my prospecting guide to Alaska. My desired target? Remote locations with large gold nuggets!
I read the book and certain places just jumped out at me. One was the Iditarod area and places like Ganes Creek and Moore Creek - tales told elsewhere. This paragraph of page 114 caught my eye:
"Placer mining in the Chisana district, first of creek gravels and later of bench and old channel deposits of Bonanza and Little Eldorado Creeks, has always been on a small scale with simple equipment. The remoteness of the area, shortages of water on some streams, and the small extent of the deposits all prevented the development of large operations. There has been little activity since World War II; the last reported mining was a two-man nonfloat operation in 1965."
Wow, that alone sounds pretty good. Nothing really about the gold however. The secret to the Placer Deposits series is not so much the books themselves, though they are great for getting ideas, like I did. The key is to use the references listed and in this case the main one is The Chisana-White River District, Alaska, U.S.G.S. Bulletin 630 (1916) by Stephen Reid Capps.
It turns out I had stumbled over the location of the last actual gold rush in Alaska in 1913. It was a small rush and did not last long, but it did mark the end of an era. The world was on the brink of war and the age of gold rushes was soon to be history. The history of the area is covered in the report starting on page 89. It is fascinating reading, but it was this note on page 105 that really sealed the deal:
"The gold is bright, coarse, and smoothly worn. The largest nugget found has a value of over $130, and pieces weighing a quarter of an ounce or over make up about 5 per cent of the total gold recovered. The gold is said to assay $16.67 an ounce."
Gold nuggets a quarter ounce or larger make up five percent of the gold? And that $130 nugget at $16.67 an ounce? Somewhere over seven ounces. That's all I needed to know. Very remote, worked by simple means, and large gold - I wanted to go to Chisana in general and Bonanza Creek in particular. Even the creek names scream gold - Bonanza Creek, Big Eldorado Creek, Little Eldorado Creek, Coarse Money Creek, and Gold Run. Now all we had to do was get there. But when I said remote, I meant remote. Chisana is practically in Canada 250 air miles from Anchorage.
To be continued.....
Chisana, Alaska location map
By Glenn in CO
Does anyone know any information on the new coil for the TDI SL and if the coil will be available separately?
TDI SL is now ... TDI Hi-Q
A new high performance coil design for added depth -
in two options
TAN Part Number: 800-0334-Hi-Q
By Steve Herschbach
ATX, TDI, GPX. What is it with detector companies and three letter acronyms? I liked it more when they were called Coinmaster or Goldmaster. At least that gave you a clue about what the detector was supposed to do.
The three detectors representing the state of the art in ground balancing pulse induction (GBPI) metal detectors. The Garrett ATX, White's TDI, and Minelab GPX 5000. You rarely see them all pictured together so I thought I would post one.
Garrett ATX, White's TDI, Minelab GPX 5000
These three detectors are all very good at what they are basically made for, which is dealing with ground mineralization and hot rocks that make using VLF detectors very difficult. In particular VLF performance is severely impeded in extremely mineralized ground. In low mineral ground a good VLF prospecting detector running in all metal mode can deliver results rivaling PI detectors with the added benefit of having good discrimination options. Anybody doing much prospecting, however, will eventually run into locations where ground mineralization and hot rocks makes using a VLF such a challenge that a good ground balancing pulse induction detector is the only real option.
The GPX 5000 represents the current state of the art, and is the easy option if money is no object. It is well designed for long hours of prospecting, has an incredible variety of optional coils, and can handle most any ground conditions with many tuning options.
The Garrett ATX provides performance that comes close to the GPX at a much lower price, with the added benefit of being waterproof to ten feet. Actually, this is only a benefit if you need it. Otherwise it makes the detector heavier than need be and limits the available coil options. Still, if the GPX is not an option the ATX would be my next choice in a new detector with a warranty. For those needed waterproof it is the only real option along with its predecessor, the Garrett Infinium.
The White's TDI is an older design but still very capable. It costs less than the other two options, and unlike the Garrett it has light weight versions and models that can be hip or chest mounted. It is a good option to explore for those on a budget or needing the most ergonomic solution. The TDI is also a very respected beach detector, like the ATX above, but it has no waterproof option.