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Dead Or Dying TDI SL Back To Life As A Spp


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A friend traded me an old Tdi Sl for my old Canon DSLR with a couple lenses. The camera was old but still worked well and perhaps worth a couple hundred at most, so I threw in a telephoto lens and we had a deal. I got a dead or dying Tdi Sl in exchange. The machine would power on etc everything seems to work except it will not ground balance and sensitivity was way down to almost nothing.  Ok so not dead but way out of sorts at least. The previous owner has moved on after having done something to the machine. Yes he had opened it up and poked about and tried to make adjustments or something to it. He has lots of history when it comes to pulling things appart followed by difficulty in putting them back together. Let's say this is not his first Humpty Dumpty moment, rather one of many.. Looking at the PCB there is nothing to adjust?  I'll take a closer look later now that the PCB is out. At worst I figured I would get some parts etc. 

Anyways, later I managed to obtain an SPP  PCB and swapped them out. Plugged everything back as I would the TDI SL PCB. Sensitivity is back to normal, seems to work well.  Pulse Delay as well as HI LOW ALL do not appear to work like they would on a Tdi SL , even though they are plugged into the board. It does appear to work as a Sierra Pulse Pro should. The SPP board is the latest with all the mods already done at the factory. The old White's rep in Australia has a few SPP boards left for about $70 US each. So I have an SPP for a while, until I can figure out how to repair the Tdi Sl PCB. I'll wait and see what happens. I've got a battery project on the boil and lots of real work to keep me busy. Locked down till mid August so I'll get busy playing with my projects during my spare time.

I'll compare it to my Tdi Sl LE and see if performance differs, should be the same.   In the image the left PCB is SPP. right PCB is from sick Tdi Sl.  I think it was a good deal and the end result satisfactory for now. Even better if I can fix the original board.. 

All the best.

 

 

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Took a photo with my new DSLR and zoomed in on the image to examine the old Tdi Sl 522293150_whatisit.thumb.png.faa81cfe9b88991a211cea9287515620.pngPCB close up. The only part that appears to be adjustable is circled. It is close to smooth/sense and ground balance. If this is out then it may be the problem? I like a puzzle..

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I wonder if Whites has any PCB’s for sale..... I’d grab another TDI BeachHunter board if the price was reasonable. I’m thinking is it worth emailing someone at White’s ?

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Just give me another ten years of trouble free operation with my XL PRO and I'll be happy.. everything else is negotiable, replaceable..

 

 

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Hi Karelian, the part you circled is the ground Ballance trim pot, just set the the main GB knob to 8 , do normal ground balance and adjust the inside one till ground ballanced .

 

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  • Steve Herschbach changed the title to Dead Or Dying TDI SL Back To Life As A Spp.
3 hours ago, karelian said:

Just give me another ten years of trouble free operation with my XL PRO and I'll be happy.. everything else is negotiable, replaceable..

 

 

Me too......I think those boards will last 50 years if the rest of the quality is anything to go by 👍

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Thanks, ROD I'll give it a go when the PCB goes back into the Tdi Sl later in the year. Looks like the only trim pot we can work on ourselves. The source of the problem? Perhaps the solution.. Good info so thanks again.

Suspect Pot.png

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Steve Howard from Whites got back to me.......they’re not selling anything from the factory which is understandable I guess, considering the state of affairs.

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  • 6 months later...
On 7/20/2020 at 6:01 AM, karelian said:

Thanks, ROD I'll give it a go when the PCB goes back into the Tdi Sl later in the year. Looks like the only trim pot we can work on ourselves. The source of the problem? Perhaps the solution.. Good info so thanks again.

Suspect Pot.png

Hi Karelian;

Did you end up trying adjusting the pot to see if it helped? I just bought a used TSI SL (ebay - less than year old - included receipt) that sounds like it has very similar problem. Won't ground balance. All tones high with GB off, all tones low with GB on with no variation with change in GB setting. Interestingly with GB off a US quarter does not register, but with GB on does. With GB on, putting the conductivity switch to low coins, nails, pull tabs, all are quiet. Switching to high all produce a low tone (including now the quarter). Same with several coils.

I welcome any suggestions on possible fixes.

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