IDX-PRO+VDI

[ampirate]

I misread your question, read it as you have 0.3 and 0.7

I would not expect any use differences using 0.3 / 0.3 or 0.3 / 0.5 - you may convince yourself in a lab - but scratching your way thru a meadow they will perform the same.

For simplicity and speed and to use up some of your spool use the 0.3

If you have lots of time on your hands make a duplicate with the Tx in 0.5 and do a head to head and post the findings. S

* When I get the Board up working, I will try Comparing Coils :
- 0.2mm, 0.3mm, 0.5mm, 0.7mm .. I just need the Windings # for Rx 0.3mm and Tx 0.5mm. The 0.2mm and 0.7mm are already done.

[ampirate]

Oscilliscope Tests

Ok,
Oscilliscope showed about 0.2V pp (yes 0.2V and not 16.0V !) at about 600hz-1000hz.

I did tap downs of the ic components,
and now I get a random squeaky sounds as I touch or wave my fingers around the TX leads.

But the volume Pot does not work, and the audio is only a whisper.
I am using a small 50ohm speaker 1/2W (could not find 32ohm) - should be close enough.

Using 9v Bat - shorted over 7808 reg - so getting about 8v.

[Koala]

Thanks,

Wound 27cm Coils :
Rx: 260 turns of 0.2mm - 122 ohms ,
Tx: 35 turns of 0.7mm - 1.4 ohms

I do not have an InductoMeter,
but I do have a small Oscilliscope,
- so I will need to work around it with this.

approximately 16V pp on the TX with the oscilloscope is a good start

[Koala]

Well, I finished soldering components down.

Not working yet though. I had to replace lousy sockets for the ICs. Need to retest the connections.

Powering it up (without Coils) , all I could get was a very quiet humm, POTs had no effect on it though.

Note: I am stuck at the same result with a Surf-PI Board that I also recently constructed.

Was hoping to Purchase Boards or Kits through Silverdog, but this Kit has been Out-of-stock for weeks,
- so I gave up ordering from him.

You can't test anything except for the power rails without a working coil

[Koala]

Hello everyone, I wanted to ask the schema for a DD coil for IDX-Pro and the various connections to the circuit, I just bought the kit from Pro-IDX Silverdog.uk. thank you ...

connections are marked on the PCB

don't worry too much which is the start or the end connections just connect the RX and TX up. Wave a coin in front of the coil if you get a double beeb then swap the RX wires over

Specs. for the windings are on the first page of this thread and the shape for the 27 DD is in the TGSL 101 pdf


If you want to use an original coil then the PCB to connector connections are on a drawing buried in the thread.

[ampirate]

first tests

Well, I finished soldering components down.

Not working yet though. I had to replace lousy sockets for the ICs. Need to retest the connections.

Powering it up (without Coils) , all I could get was a very quiet humm, POTs had no effect on it though.

Note: I am stuck at the same result with a Surf-PI Board that I also recently constructed.

Was hoping to Purchase Boards or Kits through Silverdog, but this Kit has been Out-of-stock for weeks,
- so I gave up ordering from him.

[ashefr10]

hello, to balance nulling the two coils are what I have to have 20 degrees behind rx compared to the output of the operational amplifier or then are what I need to have the lowest output voltage of the operational amplifier ?

[dgm]

Hello everyone, I wanted to ask the schema for a DD coil for IDX-Pro and the various connections to the circuit, I just bought the kit from Pro-IDX Silverdog.uk. thank you ...

[ampirate]

Thanks,

Wound 27cm Coils :
Rx: 260 turns of 0.2mm - 122 ohms ,
Tx: 35 turns of 0.7mm - 1.4 ohms

I do not have an InductoMeter,
but I do have a small Oscilliscope,
- so I will need to work around it with this.

[ampirate]

yes - edit corrected

[Koala]

I purchased them anyway (0.7mm and 0.2mm spoools).

I wound :
255 turns of 0.7mm - 120 ohms ,
35 turns of 0.2mm - 1.4 ohms

Coils seem to be about same total mass and volume.

Did you mean

255 turns of 0.2mm - 120 ohms ,
35 turns of 0.7mm - 1.4 ohms

[ampirate]

Purchased Wire

I purchased them anyway (0.7mm and 0.2mm spoools).

I wound :
255 turns of 0.2mm - 120 ohms ,
35 turns of 0.7mm - 1.4 ohms

Coils seem to be about same total mass and volume.

[golfnut]

I misread your question, read it as you have 0.3 and 0.7


I would not expect any use differences using 0.3 / 0.3 or 0.3 / 0.5 - you may convince yourself in a lab - but scratching your way thru a meadow they will perform the same.

For simplicity and speed and to use up some of your spool use the 0.3



If you have lots of time on your hands make a duplicate with the Tx in 0.5 and do a head to head and post the findings. S

[Davor]

Doubling the 0.5 will give you approximately the same cross section as 0.7 and the same Q factor. It is a bad idea to ruin a Q factor of a Tx coil.

[golfnut]

most experimenters use 0.2 for both for simplicty.


wth your wire i would make tx and rx from 0.3mm



You are likely to to run out of space using the 0.7mm and make it bulky not that suitable.