Preamp

[6666]

I never said there was a schematic. I've disclosed a method. Anyone can implement it as a circuit or in software, according to preference.

This is the method: http://www.geotech1.com/forums/showt...mit-time/page3

Thanks for finding the correct thread, unfortunately mathematical formulas are not my forte, looking at Q's description your idea seems to be to have 2 transmit pulses of different length and 2 samples for each transmit pulse is that correct ? is the sampling done with a single intergrater.

[Teleno]

TELENO

You said in a previous post in this thread that

If I search on your name 22 threads show up, I have looked in most of them, but so far I have failed to find any GB schematic
could you please give me a glue where to find this GB information , thanks.

I never said there was a schematic. I've disclosed a method. Anyone can implement it as a circuit or in software, according to preference.

This is the method: http://www.geotech1.com/forums/showt...mit-time/page3

[6666]

TELENO

You said in a previous post in this thread that

I have posted my novel GB scheme in another thread, should be tested in Aussie goldfields.

If I search on your name 22 threads show up, I have looked in most of them, but so far I have failed to find any GB schematic
could you please give me a glue where to find this GB information , thanks.

[Teleno]

Some questions that might be important for component selection and board layout for coil driver and preamp. Works with mono coil, IB coil or either? Peak coil current? Fast diode between Mosfet and coil? Snubber? EF cancel by two sample difference or bipolar pulsing(needs bipolar preamp)? Probably more.

Well, if you looked at my design you'll see it's monocoil, monopolar and no snubbing.

Since the purpose is to improve speed and signal/noise relative to Surfmaster and similar, I'm concentrating on the (pre)amplifier and keeping it simple. Further refinements can be considered once the concept is proven.

By the way, all further signal processing (GB, EF etc.) will be carried out by an MCU.

[green]

Some questions that might be important for component selection and board layout for coil driver and preamp. Works with mono coil, IB coil or either? Peak coil current? Fast diode between Mosfet and coil? Snubber? EF cancel by two sample difference or bipolar pulsing(needs bipolar preamp)? Probably more.

[WM6]

Great find! Diptrace for Linux has no time limit and 300 pins is more than enough or the project.

.

You can get 500pin/2 layer, free, by asking (registering to) editor per email. Not truly Linux, it can run under Wine.

[Teleno]

Is the STP11NM80 transistor selected for a purpose? (I.e perhaps it has the spice model built in), there are better trans if this is not the case.

Nope just because it's convenient for the sim. I've selected the IRFIBF30 which has a breakdown of 1,000V and Co < 300 pF above 25 Vds. Ron is about 4 ohm or a max current of 3 A at 12 V.

[eclipse]

Is the STP11NM80 transistor selected for a purpose? (I.e perhaps it has the spice model built in), there are better trans if this is not the case.

[Teleno]

Two boards, one for TX one for RX better noie isolation that way, to PLENTY of filtering on the Rx board.

Teleno, Express looks just fine. I didn't want to have to use another package, have you also tried DIPTRACE? http://diptrace.com/

Great 3D with it too. Limited yes, but it we do this as two boards then I can still do this as I have the full version. there is also a LINUX version - WOOT!!

Great find! Diptrace for Linux has no time limit and 300 pins is more than enough or the project.

Regarding the board question, noise is not caused by the Tx circuit. Do not mistake the flyback transient with noise. The transient is well handled by the Rx circuit, no need to separate boards.

[Sean_Goddard]

Is the plan, one board for the whole detector or maybe 2,3 or 4 sections with a board for each section?

Two boards, one for TX one for RX better noie isolation that way, to PLENTY of filtering on the Rx board.

Teleno, Express looks just fine. I didn't want to have to use another package, have you also tried DIPTRACE? http://diptrace.com/

Great 3D with it too. Limited yes, but it we do this as two boards then I can still do this as I have the full version. there is also a LINUX version - WOOT!!

[Qiaozhi]

Alas it is one forum where the rules are VERY harsh. I havn't been on there for over a year so they booted me even thought I was a paying member.

BE CAREFUL, the admin there are VERY quick to punish for infgringements. DO direct downloads, NO files on the forum, links ONLY. They have all sorts on there, I've even seen Mentor somewhere!

I will try to get back on there, I was Sidley65.

Have just re-applied.

A member from this forum invited me to Sonsivri, so I'm now registered. Yes, I've read the rules, and they're very strict.

Teleno, what Linux Distro are you running? I've used RoboLinux (brilliant). You could VM ware a Pc onto it and run Proteus (simulations too) which I just happen to have as a stand alone wink, wink.

For the record, I'm using Ubuntu 12.04, with Kernel Linux 3.2.0-97-generic-pae, GNOME 3.4.2, and Unity as the graphical shell.
To start with I didn't like Unity much, but now I've got accustomed to it.

[Teleno]

ATeleno, what Linux Distro are you running? I've used RoboLinux (brilliant). You could VM ware a Pc onto it and run Proteus (simulations too) which I just happen to have as a stand alone wink, wink.

I'm running an older Ubuntu with wine and VMware. Wine failed to install DesignSpark, can you suggest other free alternatives?

Edit: I've successfully installed ExpressPCB and ExpressSCH http://www.expresspcb.com/free-cad-software

Is the plan, one board for the whole detector or maybe 2,3 or 4 sections with a board for each section?

One board will do since the component count is low. An off the shelf (I2C) LCD+buttons will serve as user interface.

[green]

Is the plan, one board for the whole detector or maybe 2,3 or 4 sections with a board for each section?

[Sean_Goddard]

Alas it is one forum where the rules are VERY harsh. I havn't been on there for over a year so they booted me even thought I was a paying member.

BE CAREFUL, the admin there are VERY quick to punish for infgringements. DO direct downloads, NO files on the forum, links ONLY. They have all sorts on there, I've even seen Mentor somewhere!

I will try to get back on there, I was Sidley65.

Have just re-applied.

Teleno, what Linux Distro are you running? I've used RoboLinux (brilliant). You could VM ware a Pc onto it and run Proteus (simulations too) which I just happen to have as a stand alone wink, wink.

[Teleno]

Sounds like a "goer" to me. As soon as you have done the schematic I'll start on the PCB. Now, what design package are we going to use as we need a commonality. Has anyone tried DesignSpark from RS? Mechanical AND now Electrical too (that was my idea).

http://www.rs-online.com/designspark/electronics/

It's FULLY fledged and FREE! Or if you google "sonsivri" you can get any full version CAD package. MultiSim and Ultiboard etc, Eagle, Sprint and even Protel, but the setup for that takes about three hours. Let me know.

My PC runs on Linux and I've got Eagle (free limited version) for schematics and PCB. Not much, really. Eventually I can use a second PC with Windows Vista but I'd have to install the necessary CAD packages from scratch. Anyone of your preference would do, I can adapt.


I would need the invite for Sonsivri too. Here's my request: http://www.sonsivri.to/forum/index.p...=61849.new#new