Got a semi technical question for ya Tom

Regarding the fast response ( the manuals state the lag coefficient as being in the milli-second range) of the new FT machines vs the audio response length. Case in point, say you are running zero or low disc allowing the iron responses to come thru, how do they over come the audio response length to enable the users to take advantage of the fast response characteristic? Put another way since the audible responses are much longer time wise than the few milliseconds the unit is capable of reporting, in high trash scenerios are signals buffered and put thru in sequence so we don't miss real target signals or does the software logic 'cherry pick' what is put thru to the user? leaving out signals deemed extraneous.

Admittedly most areas we consider high trash probably allow most if not eveything the detector sees to come thru but on the co-located targets and areas with targets thick enough to 'give machine gun' type audio responses does the difference between the comparatively long audio response length and short lag co-efficient require consideration on an engineers part?

Tom Z

Tom

VERY good Tom! I have been waiting for nearly 3 years for someone to 'catch on' to this............and.............pose this question.

The T2/F75 is the fastest microprocessor currently available on the market today.

So..............why is the audio response a nominal 175mS audio output to your headphones/speaker when passing the coil over a coin....at a average sweep rate. BUT!!!!!!.......THEN!!!!!!!!.........IF..........BEFORE the 175mS audio is complete whilst sweeping the coil....and you pass the coil over ANOTHER target...BEFORE the audio response is complete...from the coin..............what is going to happen? This is where the T2/F75 differ from MANY other detectors. While a CZ (and MOST other detectors) would be 'busy' reporting the coin; subsequently MISSING the next (very close/adjacent) target........the T2/F75 will differentiate and report the slightest 'blip on its radar'. The T2/F75 will actually see two extremely close 'blips' that are just microseconds apart from each other. What this will do is CUT the audio LENGTH of the first target short......and report the second target. IF IF IF .... there is NO follow-on target AFTER the second target......then.....the second target will be the normal full-length audio response. If you are passing the coil over MANY ....VERY close targets.......this is where you will acquire the 'machine gun'.....rapid succession......fatiguing ...... but correct ....audio response. If you slow down the coil speed.......you will lengthen the audio responses of each adjacently close target.

Tom

Many users expect a full response on good targets regardless!! This alone probably accounts for some buy and try users dumping fast machines.

If and when FT Fisher comes out with a high end dedicated coin unit this should be switchable. Heck I might even use "long response" at times where conditions dictate if available.

Note: by long response I don't mean the enhanced response with a slower sweep on deep targets like the F70's SL mode. More like the software picking out possible good targets and giving those signals the longer response. Heck with dual processors and enhanced algorithims anything is possible! If the user had the ability to select the response characteristic to a certain class of targets that would be even better! Mo' better than using notch/disc!

Tom Z



Edited 1 time(s). Last edit at 09/06/2010 09:46AM by Jackpine.

I would like that feature..........but I am unsure if the general public would understand/like it.

without going into any great detail as to what it does. Have Marketing make up a name for it that sounds appealing and let the users decide. That's not much different than what FTP is doing now with the current machines.

Tom Z

Very interesting discussion. I've always wondered when you get into a really trashy area, or an area where iron may be masking good targets, and get high tone 'blips' if they were worth digging (and admittedly have not done so for the most part), BUT after reading this thread, it sounds like they could well be worth investigating! I've always figured these quick high tone blips were most likely falsing iron or such...maybe that's not (always) the case.

Brian,

If the high tone blip repeats when resweeping I always check it out further. Many times they are iron as you suspect. In most cases it only takes a few second to make the determination.

This thread is worth reposting:

[www.dankowskidetectors.com]

Tom Z

Thanks Tom D and Tom Z.

Tom Z I read the discussion you posted and it's well worth a read. So many little details in this hobby, but the littlest of details can make the difference between successfully recovering the goods or not. All metal hunting is so different then disc hunting that it really takes a different mind set to master in trashy areas.

HH,
Brian