Noobie questions about Surf Pi 1.2

[lmrubin]

Thanks everyone for the info about cable. Unfortunately I haven't been able to figure out why the device no longer works at all. I'm not sure what l broke, but I suppose using coax cable doesn't matter much of I can't figure out what is broken, and it seems silly to just keep replacing parts hoping it will fix the problem.

[kt315]

...... .....

[surfdetector]

Thanks for the link. Can you please explain, just so I understand, why is RG58 better than RG6? Is it because it's copper? I can't tell if it's multi stranded or not...

RG-58CU
https://www.westmarine.com/buy/ancor...02?recordNum=3

If you read the specifications chart in the link it clearly shows the differences between the cable types which is why I posted it. RG58 is multi-stranded as shown in the table.

[kt315]

ERIC"S CABLE

guys, my opinion. you have to learn to use ADVANCED SEARCH, at first. this gives you any answer on any
question, believe me now.

SVEN:
Originally used Belden RG58A/U Coaxial Cable
20 AWG stranded (19x33) .035" tinned copper conductor, polyethylene insulation, tinned copper braid shield (95% coverage), non-contaminating PVC jacket.

Overall Nominal Diameter: 0.195 in. , M17/155-00001
But found it too stiff.

http://www.ebay.ca/itm/Belden-RG58A-U-Bulk-Coaxial-Cable-Per-2-Feet-RG58-A-U-AU-RG-58-/350708108904?pt=2_Way_Radios_FRS&hash=item51a7d50e68

Then started using Marine Coax sold by West Marine, Anchor Brand.
Really flexible

http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=35292&catalogId=10001&langId=-

1&storeId=11151&storeNum=50157&subdeptNum=50187&cl assNum=50192

The coax I use now is the same but, has a polyurethane jacket similar to what Eric Foster used.
--------
Hi Sven,

The orange cable is a specially made RG58 coax. It is made for the offshore industry, specially for underwater use, with a polyurethane outer jacket rather

than pvc. This is much stronger and hard to penetrate by contact with sharp edges. Water at pressure would very quickly siphon along ordinary coax if there

was even a small cut, and enter the coil windings. Salt water would write off both the coil and the cable and even enter the electronics unless a water

blocking connector was used. Of course the orange coax is considerably more expensive, but I thought it was worth it as even for shallow water work it gives

added protection.

The cable I used is by JDR Cable Systems, part no. CAF9007. http://www.jdrglobal.com/
I haven't bought any for some years and although I can find the company on the internet, I can't find the product. Maybe it has been discontinued. The 58cu

by Ancor may be as good and it maybe worth while asking for a sample length. Both inner and outer conductors must be tin plated copper - the inner conductor

stranded, not solid.

Eric

[6666]

Thanks for the link. Can you please explain, just so I understand, why is RG58 better than RG6? Is it because it's copper? I can't tell if it's multi stranded or not...

RG58 is light and flexible, has a tinned copper shield that is easily soldered no foil, multi strand inner conductor, non magnetic, its no harder than the picture.
I only use twisted pair for my PI coils now

[lmrubin]

I just replaced the 2n3906, the 1N4001 diode, and the LM78... Now I have no sound when turning on or off or turning delay. I hope I'm not overlooking something obvious. I replaced the batteries and they test fine.

Also just replaced LM358 and the 555. Nothing... I was so proud of myself that this thing was working...that'll teach me!

[lmrubin]

Well, I thought I'd just throw it all together and try to go use it outside. Apparently, I KILLED IT (again) somehow, maybe playing with the coils.

I don't know much about electronics, but here's what I found so far with multi-meter. The battery inputs to the board shows about 11.5 volts. The ICs all seem to have both positive and negative ~4.5 to 4.97 volts. When I turn it on, there's a beep then silence. the offset is tuned to roughly 0.00 volts. So those things are good. When I wave metal above the coil, the voltage doesn't change.
So I'm not sure what's next...Previous times I replaced the transistors which was really just a guess and sometimes worked. This time I'll probably try the same thing unless someone else can teach me something else...

I just replaced the 2n3906, the 1N4001 diode, and the LM78... Now I have no sound when turning on or off or turning delay. I hope I'm not overlooking something obvious. I replaced the batteries and they test fine.

[lmrubin]

RG-58CU
https://www.westmarine.com/buy/ancor...02?recordNum=3

Thanks for the link. Can you please explain, just so I understand, why is RG58 better than RG6? Is it because it's copper? I can't tell if it's multi stranded or not...

[lmrubin]

Well, I thought I'd just throw it all together and try to go use it outside. Apparently, I KILLED IT (again) somehow, maybe playing with the coils.

I don't know much about electronics, but here's what I found so far with multi-meter. The battery inputs to the board shows about 11.5 volts. The ICs all seem to have both positive and negative ~4.5 to 4.97 volts. When I turn it on, there's a beep then silence. the offset is tuned to roughly 0.00 volts. So those things are good. When I wave metal above the coil, the voltage doesn't change.
So I'm not sure what's next...Previous times I replaced the transistors which was really just a guess and sometimes worked. This time I'll probably try the same thing unless someone else can teach me something else...

[kt315]

So, you were CORRECT!
----
lol. welcome in new chinese wonderful world.

[surfdetector]

Smart! (I'm in the US by the way, but I think I understood your meaning). So, you were CORRECT! The wire is very magnetic. So I guess it is NOT copper. So what does that mean for a metal detector though? Unfortunately I don't know what I should be using...

RG-58CU

https://www.westmarine.com/buy/ancor--marine-grade-coax-cable-bulk--P003_094_003_002?recordNum=3

[lmrubin]

looks like copper all the way through, although kt315 warns it may not be
---
take eurocents in hand. 1,2 and 5. touch them to magnet. what you see?

Smart! (I'm in the US by the way, but I think I understood your meaning). So, you were CORRECT! The wire is very magnetic. So I guess it is NOT copper. So what does that mean for a metal detector though? Unfortunately I don't know what I should be using...

[kt315]

looks like copper all the way through, although kt315 warns it may not be
---
take eurocents in hand. 1,2 and 5. touch them to magnet. what you see?

[lmrubin]

There is something wrong if you cannot get this to work, hence I asked for pictures.
At the coil end one wire connects to shield the other connects to inner conductor, for a bundle wound coil made with enamel copper wire it does not matter which wire you connect.
At the pcb end you will have two connections, these connections are where the two enamel wires you have already soldered to the pcb are, and apparently work.
One connection will be ground if you have a surf then this connection should be battery negative because you have a PFET
Solder the shield to ground
solder the inner conductor to where you had the other copper wire, it should work, do you have a multi meter check the cable connected to the coil for continuity
Is the shield made from aluminium foil , not tinned copper.

To me, the center wire in the RG6 looks like copper all the way through, although kt315 warns it may not be. The shield feels very thin and looks like aluminum...it's a ***** to solder...

[lmrubin]

There is something wrong if you cannot get this to work, hence I asked for pictures.
At the coil end one wire connects to shield the other connects to inner conductor, for a bundle wound coil made with enamel copper wire it does not matter which wire you connect.
At the pcb end you will have two connections, these connections are where the two enamel wires you have already soldered to the pcb are, and apparently work.
One connection will be ground if you have a surf then this connection should be battery negative because you have a PFET
Solder the shield to ground
solder the inner conductor to where you had the other copper wire, it should work, do you have a multi meter check the cable connected to the coil for continuity
Is the shield made from aluminium foil , not tinned copper.

Thanks for your help...I didn't want to take up your time with pics, but since you asked again...here are some pics!