Tony

9 hours ago, Skullgolddiver said:

Mine too...Bought my today... Hopefully until the end of the month I'll try it after some extra care against leakage..Honestly I thinked to skip all the modifications needed to adapt another coil based for another machine.If is true that gpx coils can run on the Tdi, then should be fine.Also, the original coil tends to float...This will float...No difference but at least a smaller and better manouvrable one.In the worst case I'll make a stainless steel upper shaft💀

SGD

Are you hardwiring or fitting an in-line connector?

I think flotation will be minimal plus I coat my coils in PlastiDip.....maybe even a solid skid plate of plexiglass glued to the coil bottom ?

On 7/13/2020 at 3:15 AM, pjrough said:

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.

Looks like this will be my future coil on the TDI BeachHunter.......

Thanks Rick for your reply.

I just want to make sure that whatever I choose works well.....I don’t need 10uS in  the rough saltwater....more likely closer to 20uS to keep my sanity. The Coiltek Platypus is out because they are no longer made. I’m considering the 8”Detech Mono....it is foam filled but being just 8” will be okay, plus I can run a rubber weight to keep it down. I feel the Detech will work optimally without any modification. I’m still waiting to hear from Eric to see if he has a suitable coil. So maybe some uncertainty with the Garrett 8” ?

Appreciate the info

Tony

I’m down to 3 White’s and 1 Minelab......👍

On 7/11/2020 at 9:04 PM, RickUK said:

I use the 8'' Garrett Mono coil on my 'Crossbow' pulse works exceptionally well,also have the 14x9 coil as well,both work well but the 8'' is my favourite out of the 2.Very good depth and also good for smaller targets like jewellery etc.

Rick

Did you have to modify the Garrett Sea Hunter 8” coil on your other detectors?

 Thanks Tony 

Have you been cleaning out your shed again Ray 👍

I managed to get a second lower half of the TDIBH / BeachHunter ID. I drilled a small hole in the clear plastic top of the battery compartment and ran the DC barrel connector lead directly from the detector PCB battery pin to my 4S1P battery pack. You could do this with the original lower half but I had a spare. This bypasses the regular setup. Just need a separate connector/lead which is very easy to make up. Now you can use much bigger battery packs but I’m okay with the 4S1P which gives me a good 7 hours.
First photo is original lower half and second is the modified....it’s only a single neat hole to run the lead through. Third photo is power source !

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.

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.

5 minutes ago, Joe Beechnut OBN said:

Tony I'm so desperate for a small coil I'm ready to take the little 8 inch off of the barracuda and try it on the "AQ"..😬

 Will that be hard to do.........in-line connector I’m guessing.

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.

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.

From my earlier experience running the Garrett Sea Hunter, the reduction in depth from the larger coil (14x9) to the smaller 8” coil wasn’t nearly as bad I thought it would be. I believe it was in the order of maybe a couple of inches on average coin/ring sized targets.......that little 8” coil in rough saltwater was sensational and my gold tally increased significantly......it never came off again. I used to run a modified Aquapulse AQ1B and I recall similar results from the big 15” coil and then moving to the 10” coil. Leave the big coils for the hardpan and lower beach low tides 👍

I plan to fit out my TDIBH with a 10” coil.....as big as I’ll go for water work !

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  👍

Detector  is now disassembled.....very easy but I took plenty of photos of the board layout just to be sure. Two points were desoldered (second photo) and the coil wires slipped out nicely. Just waiting if I can get the 3 spoke coil sent to me. Some pictures of the surgery........I will add that replacing the gasket is a bit tricky but make sure it goes on dry and no silicone grease on the gasket. Once the gasket is seated I find that adding a thin coat of silicone grease to the top cover where it seats with the gasket helps slide the cover on evenly and prevents any gasket bunching up. Only tighten the screws enough to slightly compress the oring.....do not over tighten otherwise the plastic tabs can crack. Tighten the screws a bit at a time and from side to side checking how well the gasket is seating.

Stage 2 hopefully soon 👍

3 hours ago, pjrough said:

I am starting a new project for getting land TDI sl waterproofed. It will be a long story for sure, but I ended up in the same situation and decided to go for Detech 8” Mono.

got my coil delivered to me a couple of days back.

Keep us posted on this project......sounds very promising 👍

9 hours ago, kac said:

Foam filled solid coil might be hard to swing in the water and might be too buoyant. I have used the 8" Garrett mono on my SHMK2 and it handles nice in the water. There is also the 10x14 mono that gives bit more depth and covers more area but I find it hard to pinpoint with, usually end up using the edges of the coil to narrow my dig.

Do want to point out that the Garrett coils can be prone to chipping if you bang them good. Wish they made a coil cover for it.

Thanks Kac......The buoyancy problem with a smaller 8” foam filled coil is probably okay as I got by alright with the bigger 12” dual field...it was more the resistance and coil flop that was the problem in rough water. All of my coils are coated several times with Plasti-Dip.......great protection from rocks.

10 hours ago, RickUK said:

I use the 8'' Garrett Mono coil on my 'Crossbow' pulse works exceptionally well,also have the 14x9 coil as well,both work well but the 8'' is my favourite out of the 2.Very good depth and also good for smaller targets like jewellery etc.

That’s good to know......8” is such a good size for the rougher water and poor viz 

I have been watching out for those coils but very hard to find. Hopefully the three spoke coil becomes a reality.....fingers crossed 👍

There may be a fourth option and my first choice......hope to find out soon.
This style.....⬇️

All okay....I have access to all these coils locally and for about the same price.

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?

Garrett coil

 Coiltek coil

Detech coil

Thanks Joe for the PM.......sorry by previous  post was a bit off topic and drifted somewhat.

Joe

Do the best winds for you flatten the water down or help lower the water levels?

I can see with your inlets and bays that it is site dependant on which way the best winds blow.

I was curious to know. Down here, nearly all beaches are in a North/South line so any winds from NE to SE flatten the ocean down nicely bu swells still sneak in somewhat unless these winds are sustained for some time.....which is quite often in summer when it heats up.

I guess there’s still a place for a good VLF.......would only have dug 15 of those targets being the coins and pull tabs. With the AQ, can you not eliminate the bigger targets by profiling with the coil ?