Topic: Blitzortung Build Photos

[sbuckler]

Greg,
Nice work on the GPS.  A question.  Do you know if I can use aluminum tape for my antenna shield or should it be copper?  I have a lot of aluminum tape and the copper tape is pretty pricey.

Stan

[miraculon]

Greg,
Nice work on the GPS.  A question.  Do you know if I can use aluminum tape for my antenna shield or should it be copper?  I have a lot of aluminum tape and the copper tape is pretty pricey.

Stan

If you can make a good ground connection, aluminum should work. I liked the copper because I could solder to it. Connecting your grounding wire to the aluminum tape sounds difficult.

Greg

[DanS]

What I've been doing since aluminum/tin tape is difficult to solder to is sandwiching stranded wire between 2 layers of tape. works good.

[sbuckler]

Ok, good to know.  Thanks for the replys.

[miraculon]

In response to a special request, here are some interior photos showing internal wiring of the antenna/amplifier.

I had fun with my Brother label maker as well.

Somewhat fuzzy closeup of the wires coming off of the ferrite antennas. Note strain relief.


Antenna connections at amplifier board. Those resistor/jumpers were to set the gain between 28 and 43 with 11K in series with the normal 1K resistor on board. This gives me a gain of about 36. This gives me a good compromise between my local noise source that triggers "interference mode" and reasonable distance to strikes.


Interior of amplifier as installed.


Antenna and cover opened and on shelf. This allows me to set aside the assembly for playing with gains, etc.


As it is now with warning labels. I am concerned about someone ramming a box or something into the antennas.


Same picture a little further back showing the "don't hit the antenna" label. Like I said, I like the labeller...


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Update: Finished Controller with cover and labels.

-------------------------
Greg H

[DanS]

Can't see the inside of the antenna box/lid to see how you have it but was wondering if you lined it with some of that copper tape and grounded that to circuit ground if it would help isolate "circuit board noise" from reaching the antennas. Maybe cut down on some of your interference.?.?.

[miraculon]

Thanks for the suggestion Dan. Gerry from USA TOA made same suggestion about shielding the amp box.
I might look into some of that copper spray to see if that helps.
I can see with a borrowed Tri-Field meter that there is a significant magnetic field towards the power pole and line in the back yard. I saw increased readings the night that it was false triggering. Copper shielding won't help mag field only electric field, I know.

I made a modification tonight and it seems to have helped. The op-amp circuits in the amplifier have a single power supply (12V). The half-supply references for the op amps have only 100nF caps across them, resulting in significant impedance at 60/120Hz. I ran a simulation with a CMRR injections (common mode noise). It was really bad with the 100nF and when I bypassed them with 22uF caps it made a big difference.

Although I had only 15uF available, it seems to be working a lot better as the simulation predicted. I was able to increase the gain to 70 and I am now picking up strikes in Colorado and Wyoming. Never got those before! Still not "interference mode" so far (knock on wood..)

Greg

[W7DRM (old call was W3DRM)]

Greg,

Where did you get the clear plastic box and what size is it? I like the idea of being able to see the "led lights" flashing. Sorry if this has been answered somewhere else but I couldn't find those details in the threads.

Also, what model labeler do you use? That too is a very nice touch.

[miraculon]

See this: http://www.wxforum.net/index.php?topic=18743.msg181029#msg181029

I didn't have any pictures in this posting, so it would be easy to miss.

I forgot to answer about the labeller.

It is a Brother, I think this one: http://www.brother-usa.com/Labeling_Solutions/ModelDetail/7/PT2030/Overview

Greg H.

[SLOweather]

Yeah, that looks like P-Touch output. FWIW, you can get all kinds of tapes for P-Touch labelers:
black on white, clear, red,yellow, green, blue, fl. orange
White on black, clear, blue, lime green, berry pink
red on white
blue on white
gold on black (very classy)
white on satin gold
gold on satin silver

Also flexible ID tape for cable and wires etc
Tamper evident tape
Iron on tape

I use the flexible ID tape a lot, as well as the black on clear, besides black on white.

Lots of tape widths, too...

It is a Brother, I think this one: http://www.brother-usa.com/Labeling_Solutions/ModelDetail/7/PT2030/Overview

Greg H.

[W7DRM (old call was W3DRM)]

See this: http://www.wxforum.net/index.php?topic=18743.msg181029#msg181029

I didn't have any pictures in this posting, so it would be easy to miss.

I forgot to answer about the labeller.

It is a Brother, I think this one: http://www.brother-usa.com/Labeling_Solutions/ModelDetail/7/PT2030/Overview

Greg H.

Thanks for the info and links Greg!

BTW, if anyone is interested, COSTCO has a sale on the Brother PC connected labeler, model PT2430PC for $39.99. It is regularly $69.99. The link to it follows:

• http://www.costco.com/Brother-P-Touch-PT2430PC-Label-Maker.product.11337371.html