IDX-PRO+VDI

[jlsilicon]

How about mounting the Board and POTs in a Plastic Box ?

Maybe this can create noise after a minute from the static ?

[Koala]

Well, I finally got in an Induction Meter and tested my Coils :
TX: 35mh
RX: 530mh

Considering they should be :
TX: 35.6mh
RX: 0.587mh

(Obviously I will add windings to fix this)

Is this enough Error to cause Random Noise Interference ???

Asuming a typo. then close enough. Most random noise is due to the coil shield or windings not glued together.

[Qiaozhi]

Well, I finally got in an Induction Meter and tested my Coils :
TX: 35mh
RX: 530mh

Did you mean 530uH?

[jlsilicon]

Well, I finally got in an Induction Meter and tested my Coils :
TX: 35mh
RX: 530mh

Considering they should be :
TX: 35.6mh
RX: 0.587mh

(Obviously I will add windings to fix this)

Is this enough Error to cause Random Noise Interference ???

[fluxx]

Thanks for advice. I have personally never left flux on the PCB, but my father considers it to be protection from oxide. Of course, he doesn't use flux, but rosin, and hasn't had problems. I however prefer to clean it and spray it with shellac, which I find works better and doesn't oxidize the copper over time, like rosin supposedly does.

[6666]

Hey Fluxx when you finish soldering, carefully clean all that flux off the back of the board.

[fluxx]

I have made a few photos of my IDX, that is work in progress. It's finished, but still untested. Now on to coil building (oh, boy, this is going to be fun). Wish me luck.

http://i.imgur.com/OlAnNl5.jpg

http://i.imgur.com/YsSxZ1p.jpg

[Koala]

Seem to remember someone else having the same problem a quick search of the thread failed to find it.

Also remeber the two tone did not like some ground conditions

[golfnut]

Put decent picture on

[Schatztaucher]

hi guys,

need again help of the guru`s. yesterday I built the 2 ton board of eduardo. so far everything works ok. the non-ferrous ton is loud, clear and high sound. the iron-ton is a deeper tone. but somewhat scratchy and very quiet.....
can anyone tell me why this might be?

King regards, marc

[Koala]

I have a similar question. I'm building a PI coil using the insides of a coax. I stripped off the shielding
except for a foil wrap. I could wind it with the wrap on and use that as a shield or remove it and do the
shield on the inside of the housing. Which would be better?

I think graphite makes a good resistive shield and have painted it on a cloth tape wrapped coil and also
used it on the inside of a housing. Both seem to work fine for VLF, I use the graphite paint from tractor
supply...

Can't answer for a PI but for a for the IDX I found the space blanket wrapped around the TX and RX worse than no shield at all. Tried many different ways no joy


Did see somewhere that Eric Foster got the best result by rapping the bundle in double sided tape and then spiral wrap
ribbon cable around the bundle.


Edit

Found link http://www.findmall.com/read.php?34,1174380,1175238

[Silver Dollar]

I have a similar question. I'm building a PI coil using the insides of a coax. I stripped off the shielding
except for a foil wrap. I could wind it with the wrap on and use that as a shield or remove it and do the
shield on the inside of the housing. Which would be better?

I think graphite makes a good resistive shield and have painted it on a cloth tape wrapped coil and also
used it on the inside of a housing. Both seem to work fine for VLF, I use the graphite paint from tractor
supply...

[Koala]

Thanks golfnut makes sense.If there is a solvent that evaporates the the partials will be forced together

I have fiberglass around the windings to make two very strong D shaped rings.

Was hoping to fiberglass the two together at the null point. Then use card with the graphite mix top and bottom.

Would this work or does each need to be separately shielded

[golfnut]

Ive had a go at epoxy, it doesnt allow the grapghite particles to touch, - with paint, as it dries, the particles are forced to touch.

I think its best to do the shell inner on 3 sides.

The coil facing the ground needs a shallow pot and a layer of carbon paint - this bridges to the shell sides, so conductive all around. Then final pot to flush in normal epoxy.

I think anyway, sure theres loads of ways..

[Koala]

Building another coil. Not happy with my last. Gives too many false signals.

read this thread. satdaveuk uses 1 of graphite to 4 of yacht varnish is this by weight of volume.

can I use epoxy resin instead of the varnish already have some

Coil is a DD is it better to use flat coated plates or directly applied to the windings or little difference