PROJECT ETI566

[Baterista]

Hello all, this is my first post and my third project, from the schemes of the main page, Geotech1.

[Baterista]

Receiver

[Baterista]

Transmitter

[Baterista]

Pot Core

[Dave J.]

That is beautiful workmanship for a hobby project! And congratulations for being willing to undertake the task of ferrite inductor design and construction.

Modern 2-box industrial line tracers use circuitry a lot more sophisticated than what you have there (the Fisher TW-6 which I designed in the late 1980's is a superheterodyne). However in the case of on-handle operation where the transmitter is a meter away from the receiver and not 500 meters as in off-handle utility tracing, a simple circuit where you've paid careful attention to the circuit and physical construction details can perform about as well as a "modern" circuit.

--Dave J.

[WM6]

Really beautiful design Baterista.
Phil Wait and Roger Harrison would be proud of you.
Can you say data of ferrite pot you use?

[Baterista]

Thanks Dave J. and WM6, as the pot was used a core brand Thornton produced in my country (Brazil), with the following specifications:
- L1 (Tx) NP23/17 - 4900 IP6; ungapped (ue1560)
- L1 (Rx) NP23/17 - 4900 IP6; ungapped (ue1560)
- L2 (Rx) NP23/17 - IP6 400; (ue127)


The original materials are of the type Philips 3H1 (obsolete), and should be replaced by 3H3.
- L1 (Tx) P18/11 pot core Philips, 3H1 - 3400 ungapped (ue1620)
- L1 (Rx) P18/11 pot core Philips, 3H1 - 3400 ungapped (ue1620)
- L2 (Rx) P18/11 pot core Philips, 3H1 - 315. (ue149).
There are other brands, looking for the "ue" similar.

[Baterista]

The enameled wire used is 32 AWG, wound as in the scheme, will be good.
Still about the pot core is worth remembering that this kind of material has high tolerance, the most appropriate is to get a large amount and testing with the coil, closing the pots to get the best result.

[WM6]

The enameled wire used is 32 AWG, wound as in the scheme, will be good.
Still about the pot core is worth remembering that this kind of material has high tolerance, the most appropriate is to get a large amount and testing with the coil, closing the pots to get the best result.

Did you apply a gap to your ferrite pots? If yes, what thickness and which material you use for gap?

[Baterista]

Did you apply a gap to your ferrite pots? If yes, what thickness and which material you use for gap?

No, only the pot core L2 has an internal gap of 0.24 mm, according to the example.

[WM6]

No, only the pot core L2 has an internal gap of 0.24 mm, according to the example.

Thanks. Which type of transistors did you use?

There are statement in ETI Project 566 description:
"This unit has been specially designed around a germanium transistor and a silicone type cannot be substituted."

But in parts list we can found BCxxx type of transistors only - so silicone type. How did you solve this contradiction?

[Baterista]

Thanks. Which type of transistors did you use?

There are statement in ETI Project 566 description:
"This unit has been specially designed around a germanium transistor and a silicone type cannot be substituted."

But in parts list we can found BCxxx type of transistors only - so silicone type. How did you solve this contradiction?

Yes, that is correct, I believe which refers only to the transmitter, I used the B324 (2SB324) a substitute for AC128, in the more everything seems to me OK.
Q1, Q3, Q6 - BC549
Q4, Q5, Q7 - BC559
Q8 - BC639
Q9 - BC640

[nejdet]

Hi all. Can the scheme and to post please?

[WM6]

Hi all. Can the scheme and to post please?

It is not so far away:

http://www.geotech1.com/pages/metdet...seeker_300.pdf

[nejdet]

Thank you