Whites TDI Classroom

Welcome! Log In Register
TDI and TDI Pro
Posted by: Reg
Date: October 22, 2017 09:30AM
Some people think there is some magical difference between the TDI and the Pro, but there isn't . The truth is, both use the same motherboard and only differ by these three things. First, the Pro has a vernier GB control which is done by simply inserting another pot in one of the GB pot wires. Next, the internal volume control on the TDI is removed and a new pot is soldered to the motherboard in place of the removed volume pot used on the regular TDI. Finally, here is the real important difference and that is two capacitors are changed to different values.

The TDI has .22uf caps and the Pro has .10uf caps on the differential integrator stages. Now here is the beauty, change these two caps on the TDI and you have a "poor man's" TDI Pro. The vernier GB pot isn't needed here in the US nor is the volume control.

Owners who had The mods done to reduce the noise and had the "Pro" capacitor change mod already have this capacitor change and already do have an improved poor man's Pro. I say improved because they have the noise reduction mod that is already in the SL.

Actually, the TDI noise reduction mod it is an improved version of the SL mod that makes the SL threshold so quiet. Actually, SL's made from 2015 and later have the improved version also. In late 2014 a strange "hiccup" noise was causing serious concerns in Australia on a version of the SL called the SPP (Sierra Pulse Pro). With help of Alan Holcomb (then retiring CEO of Whites providing equipment and the assistance of Luke Lindsay who lives in Australia, we managed to solve the hiccup problem. This simple mod now installed in SL motherboards since late 2014 makes the later produced SL much easier to ground balance without hurting the noise reduction. (Earlier SL's could benefit from these "hiccup" mods also).

I mention this because there is a guy who just may be doing the TDI and SL mods in the future. I will mention more when the time is right. Hopefully, that will be soon.


Re: TDI and TDI Pro
Posted by: roadapple
Date: October 22, 2017 12:24PM
Reg, You have been involved with the TDI from the beginning of its conception. I know you see the mods as an improvement to the unit ......but in the use of the first TDI did you feel the unit worked as a peak machine to find gold ? I have two original TDI machines now with no added mods and just want to keep them original as manufactured. What is your opinion?

Thanks Reg
Posted by: therover
Date: October 23, 2017 06:07AM
It's always great to see you posting here.

Re: TDI and TDI Pro
Posted by: Reg
Date: October 25, 2017 09:14AM

I would leave the original TDI's original. I am assuming you are talking about you have two of the original through the hole models.


Re: TDI and TDI Pro
Posted by: markg
Date: October 25, 2017 01:04PM
Really enjoy each time you post Reg...:clapping:

Sorry, only registered users may post in this forum.

Click here to login