whites tdi coil inductance

[daverave]

can anyone tell me the inductance and resistance of a tdi coil ????

 

[Reg]

The factory TDI coils are made with 22 awg Teflon coated stranded wire, I believe, and the inductance is 300uh. Resistance isn't critical and wire sizes between 18 awg and 26 awg work just fine. Actually, smaller wire will work also but does get warm. Personally, I use 26 awg but have used a lot of other sizes.

Reg

 

[LE.JAG]

Hi,

on the same subject
someone you he inductance / resistance of a coil 5c Goldscan

Thanks

 

[Reg]

Early Goldscan coils might have been around 250 uh to get the delay down to 10 usec but later, they were increased to 300 uh with some other changes. So, later GS 5's had 300 uh coil inductance also.

So, the TDI and the later GS 5's used or could use the same coil inductance and resistance.

Reg

 

[LE.JAG]

Thanks Reg

 

[daverave]

Hello Reg

thanks for your reply...tell me are the whites surfmaster dual field coil and the tdi coil the same ???? i cant get stranded 22 awg wire so ive used cat 6 wire...do you think this wire is suitable instead of teflon 22 awg stranded wire ??? also can you tell me the best sample width pulse to find small and larger gold rings ????
regards
Dave

 

[Frank-S]

Reg, Whats the difference between uh induction and mh induction
my meter only reads mh, thanks
Frank.

 

[Reg]

1 mh is 1000 uh, so when trying to read uh, you have to use the lowest mh setting which is 20mh on some of the cheaper units but may be as low as 2mh on others. So, a reading of .30 on a 20 mh or a 2mh setting is 300uh. A reading of .34 on a 20mh or a 2mh setting is 340uh.

Reg

 

[Frank-S]

Reg Thanks its a bit confuseing now,my brain went blank,about to turn 75.
when my thinker waikes up I will get.
Frank.

 

[Bob_T]

For what it's worth, I measure the inductance on my TDI 12" dual field coil at 350uH. Measured it at the connector at the control box between pins 2 and 4 (which are jumpered together) and pin 5. There are also two wires connected to pin 1 and I'm not sure what's going on with pin 1.

My DIY coil is measuring about 290uH and since it's not in the housing yet, I'm thinking about adding a few more windings to it to bring it up to 350 or so. Wish I'd measured the stock coil first, since my DIY coil had about 350 uH initially, I thought it was too much and I unwrapped a few windings. I think it's better to err on the side of a bit too much inductance than too little?

Bob