Which Of These 3 Coils For Underwater Work?

[Tony]

12 minutes ago, pjrough said:

 

Tony, good luck with your project.

Can I ask you to make a good photo if the PCB front side?

Can you also show where the headphones were plugged to?

 

I still have to decide whenever I will go for piezo or dynamic head speakers for my TDI project. But it nice to compare PCB, so I can track where to plug the piezos.

 

Here are two different pcb's older is from 2011 and newer is from year 2016.

I’ll take those photos for you tomorrow in the daylight  ?

[Skull diver]

You're inspiring me Tony!

I 'm wondering if the 8" AQ1 coil  can match the needed inductance

[GB_Amateur]

On 7/11/2020 at 6:03 AM, Tony said:

I have decided to finally swap out my big 12” Dual field coil on my TDIBH for something smaller. The purpose is to use in the water.

I have some pros and cons with each model so feel free to add any ideas you have.

1. Coiltek Platypus 12x8. Waterproof, epoxy filled. Maybe too long on the 12” side which sees the most water resistance
2. Detech 8” Mono. Foam filled so more buoyant but not too worried as 2/3 the size of the Dual Field coil. Good size. Waterproof.
3. Garrett 8” Mono coil. Waterproof, epoxy filled. Good size. Suitable for lower delays?

Have you seen this old thread?

Maybe more has been learned since then, but from what I've read, White's made an effort (and a successful one, apparently) to build the TDI series to be compatible with Minelab PI coils (which includes Coiltek and NuggetFinder 3rd party aftermarket coil manufacturers).  At least that seemed to work for mono coils, not necessarily for DD coils.

Other manufacturers' coils, such as Garrett's -- maybe not.  Carl seemed to think at the time of the linked thread above that some modification would be necessary for optimal operation.

It appears (and this is partly my experience but also others' experience from similar experimentation) that coils can turn out to 'work' on products for which they were not made.  But also, 'work' doesn't mean operates optimally.

I never finished my experiment of getting a Garrett Infinium LS 10"x14" coil to run on the TDI/SPP.  I found a solution for my buoyancy problem -- adding weight to the White's TDI Superpulse 150 (mm = 6 inch) mono.  That was a fun project but the results (subsequent performance) were just so-so.  I do think the Garrett coils (Sea Hunter you show, and Infinium open coils -- same housing but different(?) windings) would be a much better ergonomic solution if the electromagnetic properties are compatible or could be made compatible for optimal performance.

[pjrough]

Here is how detech 8" coil is sealed. I was thinking to open the coil and fill it up with the epoxy, but for the moment decided to glue the protection to ensure better sealing, just in case.

If the cable gland is sealed properly, I don't see problems.

[Tony]

11 hours ago, Skullgolddiver said:

You're inspiring me Tony!

I 'm wondering if the 8" AQ1 coil  can match the needed inductance

Not sure......I think stock AQ1B coils are wound for higher delays. Maybe email the company.....ask for Colin.

[Tony]

6 hours ago, GB_Amateur said:

Have you seen this old thread?

Maybe more has been learned since then, but from what I've read, White's made an effort (and a successful one, apparently) to build the TDI series to be compatible with Minelab PI coils (which includes Coiltek and NuggetFinder 3rd party aftermarket coil manufacturers).  At least that seemed to work for mono coils, not necessarily for DD coils.

Other manufacturers' coils, such as Garrett's -- maybe not.  Carl seemed to think at the time of the linked thread above that some modification would be necessary for optimal operation.

It appears (and this is partly my experience but also others' experience from similar experimentation) that coils can turn out to 'work' on products for which they were not made.  But also, 'work' doesn't mean operates optimally.

I never finished my experiment of getting a Garrett Infinium LS 10"x14" coil to run on the TDI/SPP.  I found a solution for my buoyancy problem -- adding weight to the White's TDI Superpulse 150 (mm = 6 inch) mono.  That was a fun project but the results (subsequent performance) were just so-so.  I do think the Garrett coils (Sea Hunter you show, and Infinium open coils -- same housing but different(?) windings) would be a much better ergonomic solution if the electromagnetic properties are compatible or could be made compatible for optimal performance.

I did have a good read of that thread. No absolute guarantees of optimal performance but I hope to find out soon enough.

[Tony]

23 hours ago, pjrough said:

 

Tony, good luck with your project.

Can I ask you to make a good photo if the PCB front side?

Can you also show where the headphones were plugged to?

 

I still have to decide whenever I will go for piezo or dynamic head speakers for my TDI project. But it nice to compare PCB, so I can track where to plug the piezos.

 

Here are two different pcb's older is from 2011 and newer is from year 2016.

Board attached. Headphones go into the SPEAKER socket. Down the bottom (short side) and just off to the right of centre.

[pjrough]

Thanks, Tony.

Can you tell me there  "volume" pot goes?

...whites uses the same amplified sound source for low impedance speakers and for piezos. It is good to know. Will check if I can see any difference in circutery.

By the way. TDIBH is quite loud. But there is a way to switch stock piezos to speakers headphones. Potentially it will help to differentiate low "whisper" targets.

The idea is the same to OBN Excalibur mode, but here we can use low ohm speakers, so there are plenty of options.    

[Tony]

The VOLUME socket is just to the right of the SPEAKER socket.

You are right.....the volume isn’t lacking on the TDIBH !

Not sure if the photo is clear enough.....took the photo indoors as it’s wet and gloomy outside.