07-30-2019, 11:30 AM
I've done a lot of testing on the TDI SL, and can verify that making, or buying a 4-cell 16v battery pack will increase both depth and sensitivity of the detector. That's mod #1.
Also, one problem the SL has it that the sweep speed is really critical on small nuggets, or other tiny targets. This can be eliminated by changing two of the filter
capacitors (C20, and C21), and replacing them with caps that are half the value. The factory value is .47ufd, and they should be replaced with .22ufd. This may result in a
slight increase in ground noise, but a dramatic increase in the range of sweep speeds that will detect really small targets.
![[Image: S6CFHWd]](https://ibb.co/S6CFHWd)
The third mod is a bit more ticklish, so you may need some help from an electronics tech. This mod was made on the new Special Edition model from Whites, and may
have been done on all units sold since 2015, at least that's the rumor. It for sure has been done on the SE model. This mod can be done in stages, or, like the factory, done all at once. The first stage is to remove capacitor C56. The second stage is to remove capacitor D20. The third stage is to remove capacitor D21, and install a jumper
across two of the three solder locations where the legs attach. Here's a pic of the mod for D20 & 21"
![[Image: 4pfx3X6]](https://ibb.co/4pfx3X6)
You can see that D20 is gone, and a jumper on two legs of D21 has been installed.
Pic of location of C56 that has been removed:
![[Image: HXQBPCZ]](https://ibb.co/HXQBPCZ)
Looks like my pics didn't show up. Not sure how to fix that OK...here are the pics, in order., that should have been in the first post
[attachment=10908]
[attachment=10909]
[attachment=10910]
Also, one problem the SL has it that the sweep speed is really critical on small nuggets, or other tiny targets. This can be eliminated by changing two of the filter
capacitors (C20, and C21), and replacing them with caps that are half the value. The factory value is .47ufd, and they should be replaced with .22ufd. This may result in a
slight increase in ground noise, but a dramatic increase in the range of sweep speeds that will detect really small targets.
The third mod is a bit more ticklish, so you may need some help from an electronics tech. This mod was made on the new Special Edition model from Whites, and may
have been done on all units sold since 2015, at least that's the rumor. It for sure has been done on the SE model. This mod can be done in stages, or, like the factory, done all at once. The first stage is to remove capacitor C56. The second stage is to remove capacitor D20. The third stage is to remove capacitor D21, and install a jumper
across two of the three solder locations where the legs attach. Here's a pic of the mod for D20 & 21"
You can see that D20 is gone, and a jumper on two legs of D21 has been installed.
Pic of location of C56 that has been removed:
Looks like my pics didn't show up. Not sure how to fix that OK...here are the pics, in order., that should have been in the first post
[attachment=10908]
[attachment=10909]
[attachment=10910]