Iron audio volumn level for CZ6a?

The CZ6a (as most detectors) will give an iron tone for targets that are too deep for it to reliably identify. Many times when beach hunting, I will dig those weak sounding iron tone signals knowing that they could possibly be something good. My problem is that all the iron surface trash, which comes in at maximum volumn levels, is very fatiquing to my ears. I would like to limit the maxium volumn level of this iron surface trash without losing the weaker "non-identifyable" iron signals. I have read of some detectors having an iron audio volumn level, and is what I'm looking for to add to the CZ6a.

I would think that adding a small limiting circuit of some kind to the iron audio output on the PC board would do the trick,and it might be as simple as adding a resistor to the iron audio output, trying different values until one suited my ideal of audio level. A small variable resistor might be used and I could adjust the iron volumn internally to my satisfaction before reassemble. If this worked, I could possibly move the variable resistor to the housing in some manner, maybe using a weather resistant pot to adjust the volumn level externally instead of internally. I would rather not have something plugged into the earphone jack to do this as I dislike things hanging on to my detector :-)

I've concidered limiting the output volumn level of Disc 0 and combining it with the unaltered volumn level of Disc 1. All of the output from Disc 0 would be lowered, but should not be noticed when combined with the Disc 1 which would remain at normal levels, and I should be able to hear the audio of the added lower volumn level of the iron from Disc 0. Disc 0 would work as normal but at a reduced volumn level, and Disc 1 would be at normal level and still hear the lower output level of iron from Disc 0.

Any and all help as to how to go about this would be greatly appreciated. I would like to know if this is feasible and maybe some help as to where in the circuit to actually add this modification. I'm handy with a soldering iron as I do a good deal of it in my line of work, but my electronic knowledge is rudimentary at best.

Please feel free to advise :-)



Edited 3 time(s). Last edit at 12/03/2012 12:20AM by connortn.

maybe ask this question on the geotech forum?

Seeker41...

I did but there are some really savy guys here that have helped me before and I wanted to get their opionion. Thanks for the recommendation.

Would you consider something like this?

[www.diguniverse.com]

Keith

Keith Southern Wrote:
-------------------------------------------------------
> Would you consider something like this?
>
> [www.diguniverse.com]
> CESSORIES/EQ-50.html
>
> Keith

I use one of these at times, mainly due to my poor hearing. If I were you I woud give it a try before doing anything internally to the CZ.

We all have different hearing and myself hear low tones better than high ones and yep that low tone really is harsh to me if I want to hear the high tones clearly so I just disc out the iron as I really don't feel your first sentence is true as from CZ experience feel perhaps a silver dime may drop to mid tone when it reaches its max detection depth but never a low iron tone.Of course for relic hunters this would be counter productive.
I know what you are trying to achieve but would experiment with the volume levels before I tried to mod your unit and perhaps one of our techies could chime in.
If you didn't know volume 1-5 is modulated and 6-10 gradually all target deep or shallow sound the same.
Don't fix what ain't broke comes to mind but with the abilities of some forum members perhaps what your asking might be achieved..

keith, thanks for posting the link for the eq!!! i started to buy one a while back. i have 30% hearing loss and being able to adjust the tones would be a great help. that could probably be adjusted to the users liking and then placed inside thew control housing.

i have posted before that i would love to be able to adjust down or up or even eliminate the individual audio level of specific tones on a detector. instead of vid and display features give me a detector with a bunch of audio control features!!!!!
chuck.

I would much rather do the modifications inside the housing. I do delicate work all the time. You have to be good to please musicians when you start working on string instruments. I do cavity routing, re-wiring, fret replacing, neck settings, finish work and custom work on instruments in the $10,000+ range in addition to repair work on antiques for the auction house, which is next door to our business, on items in the thousands of dollars. I've completely stripped old mac computers, refinish them, add custom parts and circuit board mods to have a finished product that looks factory made and is capable of much more than what it was originally designed for.

I'm not afraid to work on things. I know that some people try hacking things and it either never works afterwards or it looks like it fell of the back of a turnip truck :-) My job requires that I do good work or I wouldn't be there. My last mod to a CZ was purchasing a pair of the now discontinued Auvio headphones and after disassembling the transmitter unit, built a minature voltage regulator so that I could power the transmitter from the detectors batterys instead of the 4V rechargable battery that came with the transmitter. I was able to add the components of the voltage regulator to the very small area that the original battery covered (about 1/2" X 5/8") by drilling the circuit board with very tiny number drills and wiring it on the back side.

I have machinist skills with lathes and milling machines, electronic test equipment and many tools for doing delicate work. I have rarely had anything that I didn't customize to add features to and if I don't have a tool for a job, I make it. My father and brother are/were first class radio comunications license holders so I grew up in electronics, I just never got deeply involved in it as they did. Dad was chief enginere for WBEJ radio and practically designed and hand built everything there. My brother was top man in telecomunications at ATT for many years. Some of it had to rub off and has come in handy in my field of work now.

So don't be afraid that I will take advise and ruin my detector. Even if I were to damage it, it's mine and it's not going to make me homeless :-) I'd much rather do some modifications to a unit (the CZ6a at this point) that I truely like and cannot find a better detector for my needs, and make it more suitable to my way of detecting than to spend thousands of dollars looking for the elusive detector of all detectors knowing it's not out there.

This is a bit long, but just wanted to give some background as I know the hazards of advising someone and not knowing their capabilities. So please advise away :-)

My bad as I thought you were all thumbs like myself and do mess around now and then and have had units apart for adjustments.

My feeling you have the ability and indeed comfort and personal preferences makes for more enjoyable detecting.

Any of you knowlegable techies out there to help him out?

I saw the request on Geotech1 (same thread title), and thought Connor was going to tell us how to do the mod, so I looked at the thread and was disappointed when it turned out he was ASKING how. A question mark would make all the difference. I've never seen a circuit diagram for a CZ6, only a CZ5. Without a circuit diagram, you are stuck, and proposing 'adding a resistor' is pure speculation. The CZ5 cct is available on Geotech, I've no idea how similar it is to the CZ6.
[www.geotech1.com]



Edited 1 time(s). Last edit at 12/02/2012 06:50PM by Pimento.

I've just downloaded the CZ5 circuit and examined it. I reckon you could work out when the machine is giving an iron tone using the 3-bit logic that controls the analogue switch that selects the tone frequency. But how you would use that to control the volume in a limiting way is anyones guess, hours of oscilloscope work would be needed to crack that one. The circuit diagram seems a bit incomplete in that area too, an analogue switch is not shown.



Edited 1 time(s). Last edit at 12/02/2012 11:02PM by Pimento.

Sorry for the misleading header Pimento. I'll try to edit them. (...was able to edit the heading here but didn't see a way to edit the heading on Geotech)

I was hoping you would join in as your help with the voltage regulator with my other project was great. I guess it may be down to some expermenting and circuit tracing to figure out what to do. Maybe Tom can give some hints or insight since he knows the circuit well. I wouldn't think it would be something that would be concidered breaking confidentiality with Fisher. I wouldn't want or ask him to do that.

I am thinking that I just need to locate the output of the iron tone on the circuit board. Each tone must have an audio oscillator, so just finding the correct one and it's output would be a great start. I'll see what I can come up with and if I get something working, I'll try to post it here in case others would like to have an "iron audio" on their CZ6a.



Edited 1 time(s). Last edit at 12/03/2012 12:24AM by connortn.

I guess you need to read my comments with the circuit diagram in front of you. There is NO iron tone oscillator. There is one oscillator, and its tone is switched between 3 different frequencies, by switching in 3 different resistor values. The logic signals that determine which resistor is switched in can be accessed, and thus you can figure out when 'iron tone' is active - looks like 000 is iron to me, so a 3-input OR (or a NOR) gate would detect that. Then you can switch in your audio limiter/reducer. But... you need to have an idea of the actual 'volume determining' signal levels in order to work out how and by how much to attenuate them (one signal determines volume, a seperate signal determines frequency). Lots of 'scoping, and trial and error.