Building a red system

[Jack Zielke]

I meant to post this earlier but I kept getting distracted. My wife bought a weather station in 2006. She wanted to add a lightning detector to it soon after. This was our anniversary present to each other (12 years woo!). We are really happy with this system.

Before the kit arrived I ordered some other parts.
GPS Antenna http://www.ebay.com/itm/261553309782
Discovery board http://www.mouser.com/Search/Refine.aspx...4DISCOVERY
Shrink tube http://www.ebay.com/itm/111434272257
Magnet wire http://www.amazon.com/gp/product/B0082CUNVE/
R/C foam rubber http://www.amazon.com/gp/product/B0006NATXY/
12 50x7.5 mm ferrite rods http://www.surplussales.com/Inductors/Fe...rRods.html
Heat gun from Harbor Freight

I followed these directions to make 2 antennas http://www.wxforum.net/index.php?topic=19914.0. Well, I basically followed them. If you read through the comments you will find some changes to the process. I did not glue the ferrite rods together. I pressed them together and then put 1 wrap of electrical tape to hold them together. I put the rods in the shrink tube and used the heat gun. They are tightly held together. I wrapped the magnet wire on the outside of the shrink tube. I used electrical tape every so often. Ok, I actually deliberately spaced the electrical tape to be at the end and at the center of each rod so that the humps were evenly spaced. There is a tape hump where each rod touches the one next to it. After wrapping the wire I put the entire thing in another shrink tube and heated it up. I wrapped each antenna in the R/C foam (like in the directions) and then slid the antenna into 3/4" PVC. I did not use the metal foil shield. I used the ribbon cable shield. https://forum.blitzortung.org/showthread....01#pid4401





At this point I waited until Sep 24. Ok, the post office had it and gave me a note about it on the 23rd but I did not have it in my hand until the 24th. Woo.

The *wonderful* directions from W3DRM said to make the H-field amp first. I admit that I made the control board first. I soldered 1 module per night. The amp would not have been very entertaining by itself but the control board could be plugged into my network and I could play with the GPS and I could register the hardware. I also wanted to get a little bit of soldering in before I attempted those surface mount op-amps.

The control board soldering was pretty uneventful. I had already loaded the firmware on the discovery board the day it arrived so I was ready to plug them in and turn it all on. I had a little bit of Goldilocks fun with the phone chargers. The first one I plugged in was too low (4.0), the second too high (5.3) and the third was just right (5.1).

On Thursday I made the H-field amp. I had some trouble with the surface mount parts. It would take until the E-field amp before I remembered how I like to do those. I like to put a very small amount of solder on the pads before I put the component on. Ah well. I plugged everything in and had 1 working channel. I plugged the amp into the second input to see if I had messed up something on the controller board. Same results.

On Friday I decided to make the E-field amp instead of debugging the silent channel on the H-field. If I got the E-field working then the detector could use it while I was fixing the H-field. Alas once I was done the E-field did not work either. Crap.

Saturday I took the H-field amp offline and put a nice (less than 1 Vpp) quiet signal into the antenna inputs. Years ago my wife bought me a signal generator for I think $1 at a surplus auction from UTC. The General Radio 1210C and surplus oscilloscope did me good. I found that the signal went into IC7 but did not come out. A quick touch up and both channels worked.

On the to E-field! The pre-amp had power but the signal was not making it out. A continuity test showed that 2 of the 8 pins on IC1 were not connected to the board. That would be pins 3 and 6. I believe that is the input and the output. Yeah, I would mess up both of those. Some touch up work there and E-field works. Woo. I had a little bit of fun changing the frequency and watching the output change on the 3 output pins.

All in all this was much easier than my Elecraft K1.

A friend of mine gave me some 3/4" pvc so now to complete the installation I think I only need: 3 end caps, 1 junction box and 2 pieces of shielded cat 5/6 cable. Right now station 1181 still has its antennas in the computer room.

[W3DRM]

Jack,

Nice work on the ferrites!

Your signals don't appear to have much noise in them so your location must be pretty clean. I watched your signals for a few minutes. At first i saw both H-field and E-field but now, for some reason, only H-field and of that, mostly only Channel 1 (Red trace). There is an occasional Green trace but not very often. Are you sure everything is connected solidly? Check the antenna connections and ethernet & coax cables for tight connections.

• Station 1182: http://www.lightningmaps.org/blitzortung...ion_id=105
  

Are you running in manual mode or Automatic?

Also, are you a ham? You mention the Elecraft K-1...

[Jack Zielke]

Thank you =]

I am very pleased with the noise situation so far. I live out in the county (Harrison is unincorporated) but I am in a neighborhood so at times I am at their whim. Next door neighbor installed a street light (goodbye stars) and then moved less than 3 months later. No electric fences out here, people just let their dogs roam.

I will double check green and the coax. The H-field antennas are both just the magnet wire in the terminals right now. I will do better once they are mounted, but I want to make the wires the same length and I do not know what that will be until it is mounted. I was planning on soldering stranded wire stubs to the magnet wire to give the terminals something to bite into. I put the E-field in pvc pipe just before creating this thread, I might have loosened something there as well.

I have it in manual mode with both automatic checkboxes checked. Currently my gains are 8x8 for H and 10x5 for E. Looking at the signals page they are 10x4 for H and 10x2 for E. I did not think they could be higher than the settings page. Possibly this is one of those settings sharing things that I need to look out for.

Yeah, I am a ham. When my wife and I were dating we both took the test at the same time. Different last names, different addresses. We ended up with consecutive callsigns =]

KG4GJY for me and KG4GJX for her.

Thanks again!!


Jack

[W3DRM]

I would suggest that you use only "solid" wire for the antenna lead-in stubs and do not twist the leads from the ferrites. Any twisting introduces an inductance and capacitance which is not desirable. I simply used some 18-gauge solid wire I had on-hand. It was soldered to the ends of the leads and then attached to the terminal strip. Worked fine for me. Keep the lengths of the wires from the ferrites to the Amp board as short and as straight as possible.

Play with your amp gain settings until you get them optimized. Cutty has a great walk-through on adjusting the E-field on the WXFORUM. You'll find it in the Blitzortung section of the forum.

• http://www.wxforum.net/index.php?topic=22710.0
  

73's - Don

[Jack Zielke]

Thank you. Solid wire only, no twisting, as short as possible. I put my H-Field amp in a 1.5" junction box and then used reducers to get down to 3/4" for the antennas.





I just got the shielded CAT6 cable in this week. I finally got the antennas in the attic so they are no longer in the computer room. While I am excited about that I don't think the E-Field antenna is going to stay where it is. Right now it is attached to a rafter in the attic. I do not have a metal roof and while I am sure that helps, everything I have read on the forum says I want air below the E-Field probe.

I think there are 3 easy places to put it. Well not easier than leaving it where it is, but not that bad. I have a center ridge vent and I could put it directly underneath it. That would put it at the highest point possible but still be protected from the elements. My house is a split foyer. Half of the basement is underground in the front of the house. I am on the ridge of a hill and the back yard is level with the bottom of my house. I mention this because I could send the wire for the E-Field out a vent under the overhang in either the front or the back of the house without too much trouble. The front of the house is closer to the ground but would be a shorter run of coax. The back of the house is farther away from the ground but would be a longer run.

I could also just see how it performs as it is for a little while.

[cutty]

Thank you. Solid wire only, no twisting, as short as possible. I put my H-Field amp in a 1.5" junction box and then used reducers to get down to 3/4" for the antennas.





I just got the shielded CAT6 cable in this week. I finally got the antennas in the attic so they are no longer in the computer room. While I am excited about that I don't think the E-Field antenna is going to stay where it is. Right now it is attached to a rafter in the attic. I do not have a metal roof and while I am sure that helps, everything I have read on the forum says I want air below the E-Field probe.

I think there are 3 easy places to put it. Well not easier than leaving it where it is, but not that bad. I have a center ridge vent and I could put it directly underneath it. That would put it at the highest point possible but still be protected from the elements. My house is a split foyer. Half of the basement is underground in the front of the house. I am on the ridge of a hill and the back yard is level with the bottom of my house. I mention this because I could send the wire for the E-Field out a vent under the overhang in either the front or the back of the house without too much trouble. The front of the house is closer to the ground but would be a shorter run of coax. The back of the house is farther away from the ground but would be a longer run.

I could also just see how it performs as it is for a little while.

The E field probe must be VERTICAL... and for best results, should be OUTSIDE, away from structures, and noise...

[Jack Zielke]

everything I have read on the forum says I want air below the E-Field probe.

I think there are 3 easy places to put it.

The E field probe must be VERTICAL... and for best results, should be OUTSIDE, away from structures, and noise...

I really appreciate the help. For my specific situation I listed 3 locations and I was trying to weigh the differences for:
Total height above the ground
Total air space between the probe and ground
Total coax length

I should not have added the photo of the temporary location. That is as far as the coax would reach and I need to choose a final location so I can buy the right length. I did not realize that it would cause you to reply without reading the post. It also might cause others to make the same mistake and think it is a suggested location. I will remove it.

Thanks again for your help!