Omega coil

[wam]

Hi, is it right that omega coil is better performing than concentric coil?
I have found on the street cut of china VLF coil. I have cracked it (now it looks terrible).
It has concentric winding inside but it has omega former not used. Is it not use because omega type needs more work?
I will rewind this coil to see if can get it better – should I use omega type?
Regards,

[homefire]

This may help you.

[6666]

Have not tried one myself

[wam]

Do You have any formula about number o TX RX turns so it will be balanced?
Regards,

[Qiaozhi]

Do You have any formula about number o TX RX turns so it will be balanced?
Regards,

As far as I'm aware, no specific TX / RX turns are required for correct balancing. You simply move the RX coil until balance is achieved, in the same way as a DD coil.

[kliner]

How do you calculate the inductance of the TX coil, can you consider it to be 2 coils?

[Qiaozhi]

How do you calculate the inductance of the TX coil, can you consider it to be 2 coils?

Although you can consider the TX of the omega to be two separate coils, you cannot just subtract one inductance from the other, as they are different sizes and offset from each other. Unfortunately, the only approach (at the moment) seems to be trial and error.

[wam]

Hi, I use inductance meter and estimate. As it is coil has TX 1.8 mH (6.4R) and RX 2.09 mH (15.5 R). It is measured on the cable. I have some other notes for this coil, like cap value and all connections - it is second the same coil broken by me. Well, I am wandering if I can mod it so RX will be like 100 mH or so . This will be problem with balance.

[kliner]

What are the advantages/disadvantages of the Omega/concentric/ Double d coils, I fancy having a go at an Omega for my IGSL to see how it compares to a DD

[IBGold]

Also known as a 4B coil I built a few early on for Minelab PI use but were not overly impressed with the performance for what I wanted so went on another track.

Regards, Ian.

[sido]

Hi Wam, for what model detector is this Coil???

I am very interested in other information you may have on this coil in the picture you posted.

Do you have any other good photos showing the copper wires???.

Do you know the wire size used for TX and RX???

What's the value of the capacitor???

What is the pin out connector diagram for TX and RX.

How is shielding made?, looks to me sprayed graphite.

Any other information will be help full, thank you.

Regards Sido

[wam]

Hi Wam, for what model detector is this Coil???
How is shielding made?, yes ... sprayed graphite.

Hi it is from MD1020 but some times HP1020 or GC1020 or other names. I have seen some factory docs and it was GC1020. The good thing is that they all look the same.
I have schematic for coil and more photos just need to dig it out. The new detector sales for about $150. Range for coins about 18 cm.

[WM6]

What are the advantages/disadvantages of the Omega/concentric/ Double d coils, I fancy having a go at an Omega for my IGSL to see how it compares to a DD

Omega and CC have similar field coverage at swinging which is worst than by DD coil (DD has almost full coil diameter coverage at whole depth sewnsitivity).

Inner coil manufacturing adjustments at Omega an DD are similar, CC need bucking coil for adjustment.

Depth depend on many manufacturing factors, but maybe DD go a little deeper than other two at same coil diameter and build quality.

Pinpointings are not the same too, best with CC.

The GEB, CC is in general more stable. etc.

I always marveled at some of the unusual form of Chinese coil, now it is clear why such design.

[lonelyWOLF]

hi wam..
I found this schema somewhere in the forum. is it same md1020 ?

[sido]

Hi Wam, thanks for the reply.
Here in Australia we have the same model but it is labeled Goldsnoop pro. I dont have this detector.

I have the original Goldsnoop without LCD, model (MD 1023, GC1023, Gold Century etc.). Coil covers look the same but may have different windings, depending on frequency.

Like you said they all look the same the coil covers but operating Frequency is of interest.
I suspect most of the models work on the same frequency of 6.6 - 6.7 khz. The value of the capacitor in your photo might gives us a idea of frequency....

I want to build a replacement larger coil and a smaller coil. I read somewhere that the TX outer coil windings for (MD1023) is in series with the inner coil windings and the outer has less turns than the inner TX coil. The RX coil is in the center and wound as per usual for concentric configuration. The person who wrote some details about this coil said that it is effectively a 4 inch coil with that configuration. (Due to more inner TX windings)

Do you know the working frequency for your detector??

Waiting for the Specs, factory docs, schematics, whatever information you could please dig out. Thank you.

Regards Sido

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