Author Topic: My home-made ferrite antennas  (Read 46463 times)

0 Members and 1 Guest are viewing this topic.

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #50 on: March 30, 2014, 08:45:34 PM »
Don, I forgot to ask if the connectors (look like DB9s) in the shielded wire from the antenna to the preamp are a nice touch, but again if one isn't anticipating a lot of experimentation with trying ferrites vs. balls vs patch vs styrofoam board, is there a reason to put the connectors in there?

You have a lot of experience and were on the bleeding edge, so you seem to attract the most attention for questions on this project.  Let us know if you want us to back off...

Dale
ECWx.info
&
ECWx.info/t/index.php

Offline dfroula

  • Forecaster
  • *****
  • Posts: 533
Re: My home-made ferrite antennas
« Reply #51 on: March 31, 2014, 04:39:21 AM »
Dale,

I sure don't back off on the questions when I'm trying to figure something out.  :eek: Please ask as many as you like.

Well, funny you should mention it.....the db9 connectors did not work out at all. I have a huge box of surplus Amphenol DB9 shells and male/female solderable connectors. The problem was the connector body is loose within the aluminized plastic shell. Any movement of the connector in the shell caused severe noise in the receiver. Also, the cable lengths in the picture are far too long.

Now, I just use a terminal strip on the shortened cables to the antenna. I have another very short set of cables perymanently connected to the amp in the enclosure, going to the other side of the terminal strip. It works fine.

Don
« Last Edit: March 31, 2014, 04:57:02 AM by dfroula »

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #52 on: March 31, 2014, 11:41:28 AM »
While I wait for my shrink-tubing to arrive later this week, I just realized that I don't have a heat-shrink gun. Any suggested brand better than another? I do have a Harbor Freight store within 20 miles and may just go there to pick up one of their cheapies. They have several models on sale at the moment.
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #53 on: March 31, 2014, 12:07:24 PM »
I just now am cooling off my Harbor Freight gun after heat shrinking with it.
I used to use my wife's hair dryer with minimal and mixed success.

I found this orange thing at Harbor Freight and was a bit skeptical, especially for the price.  But it has two speeds, I have NEVER burned a piece of tubing with it, unlike the efforts with matches/torches/soldering iron/ lighters/etc.

I am sold on this low cost gun.  I've made many more heat shrinks than I would have, just because this takes the unknown out of shrinking and love the look (no solder globs on the tubing) and consistent results.

Go for a nice Monday drive, use your 20% off coupon you can find on their site if you don't already have a coupon for that specific gun.

I have to say, the source for the shrink wrap that I think Don pointed us to seems to be top notch.  I again thank all those who have tread the path before us for the tips they've given.

Dale
ECWx.info
&
ECWx.info/t/index.php

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #54 on: March 31, 2014, 03:14:19 PM »
Thanks Dale. I'll try the HFT gun and see what happens. Tubing due in on Friday so it gives me time to get the tool beforehand. I've also had less than satisfactory results with my wife's hair-dryer as well as the other methods you described. I do have a 20% off coupon so will use that too.
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 2780
    • Frankfort Weather - TwinHollies WeatherCenter
Re: My home-made ferrite antennas
« Reply #55 on: March 31, 2014, 04:23:07 PM »
Gee, wish we'd thought to mention WHD for heat shrink... would have suggested it might be ineffective...  #-o

Anyway, you ever thought about how many neat things you can do with a HAG and various types of plastic and shrink wraps??  :idea:  I mean besides burning the wings off pesky flies?

CoCoRaHS KY-FR-1  CWOP DW5536

       Blitzortung
       689
& 1439

sferics.us

 


Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #56 on: March 31, 2014, 04:51:26 PM »
Gee, wish we'd thought to mention WHD for heat shrink... would have suggested it might be ineffective...  #-o

Anyway, you ever thought about how many neat things you can do with a HAG and various types of plastic and shrink wraps??  :idea:  I mean besides burning the wings off pesky flies?

Okay, it's probably clear to everyone else but me but, what does WHD and HAG refer to? I can't seem to come up with anything they might stand for except for "World Health Day" for WHD which I am certain isn't the correct answer...
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 2780
    • Frankfort Weather - TwinHollies WeatherCenter
Re: My home-made ferrite antennas
« Reply #57 on: March 31, 2014, 05:08:36 PM »
 
Gee, wish we'd thought to mention WHD for heat shrink... would have suggested it might be ineffective...  #-o

Anyway, you ever thought about how many neat things you can do with a HAG and various types of plastic and shrink wraps??  :idea:  I mean besides burning the wings off pesky flies?

Okay, it's probably clear to everyone else but me but, what does WHD and HAG refer to? I can't seem to come up with anything they might stand for except for "World Health Day" for WHD which I am certain isn't the correct answer...
:lol:  :lol:  :lol:
I simply couldn't resist seeing who'd bite...
Wife's Hair Dryer and Hot Air Gun...  :twisted:

It's part of my illness...
Mike

CoCoRaHS KY-FR-1  CWOP DW5536

       Blitzortung
       689
& 1439

sferics.us

 


Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #58 on: March 31, 2014, 05:34:39 PM »
Having choked on PTZ in another thread (Pan, Tilt, Zoom) for a webcam, I was licking my wounds and didn't bite.

Nice bait, though.

ECWx.info
&
ECWx.info/t/index.php

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #59 on: March 31, 2014, 05:51:57 PM »
 :oops: Okay, ya got me!  =D> However, if one doesn't ask questions, one will never learn...  ](*,)

So, for the record, the WHD doesn't work so good as a HAG for anything but it's originally intended use but, I bet it would warm up those cold sheets on a cold winters' night...  \:D/
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #60 on: March 31, 2014, 08:04:11 PM »
OT== speaking of wintery nights, we are struggling to melt snow, but warm winds and 50s today helped a lot.

Mud knee deep, neighbors with livestock have them all muddy.  My livestock is a German Shepard Dog who is inside some of the time and we are going through dog towels trying to keep the mud to a minimum.

And to top things off, the rest of the week has an even chance each day of snow, with Friday expected to have some 4 to 9" across MN and WI

When will it end?

ECWx.info
&
ECWx.info/t/index.php

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 2780
    • Frankfort Weather - TwinHollies WeatherCenter
Re: My home-made ferrite antennas
« Reply #61 on: March 31, 2014, 09:27:47 PM »


When will it end?


I'm calling it Done.  Put out the CoCoRaHS ETogage today, and reinstalled inner cylinder in the rain gauge. x'd fingers.

CoCoRaHS KY-FR-1  CWOP DW5536

       Blitzortung
       689
& 1439

sferics.us

 


Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #62 on: March 31, 2014, 09:47:46 PM »
OT == We're under a winter weather watch tonight! Supposed to get down to around 28F tonight with blowing snow. The SIERRA ridges are looking at 24 inches overnight. Nothing like a late snow storm. Unfortunately, it will only bring the snowpack numbers up to around 40% of annual averages. Still way low and will likely make for water restrictions being enforced this summer.
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #63 on: April 04, 2014, 09:27:09 AM »
With 4-6" of wet heavy snow last night and this morning, with more possible, I'm finishing up my antennas.

I have wondered about the live rubber shock protection and think that I might just take some square cotton cosmetic make up pads that are about 2" square and sort of 1/4" thick and roll a couple around the middle of the rod, then after it is in place slide a cylinder of the cotton up over each end, watching the delicate wires.  The whole thing will be pretty sealed and will never get wet so I don't see that the cotton will saturate, but yet allow easy removal if ever needed in the future.

I measured the resistance of my winding with a sort of accurate dvm, and get about 5.4 ohms.  Is this the ballpark?

I have downloaded the latest RED documentation from Blitz, and looked at the nice pictures.  Most of the installs for ferrite antennas seem to NOT use the shielded wire to connect to the preamp, they just come out and solder the winding wire to a thicker wire or pin to make sure it gets good connection to the screw downs on the preamp board.

If one came up with something like a nice bread (literally!) board of plastic to mount the ferrite assembly to, ran the magnet wire out through the L box and directly over to a preamp box mounted near the junction of the two arms, would that have any disadvantage to doing what Don has shown with the shielded wire?  I assume for the time being that I'll be so ecstatic when my system is up and running that I'd not twiddle with antenna swaps and other tweakings at least for this lightning season, so being able to easily swap antennas and tweak wouldn't be a high priority right away.

Finally, I am loath to cut off any excess wire from the rods, since I have about a foot and a half to allow for errors, unexpected breakage, etc.  That would lead to a rat's nest of sorts, but to keep the safety net of a few extra inches, could one just make a short loose coil maybe about an inch in diameter and leave that in the protected area of the L box, or would having those coils (four total, two for each of the rods) interact or act as an undesirable influence on the antennas themselves?

Thanks. Dale (off to start the of Cub Cadet and do a little snow throwing for one last time.)
ECWx.info
&
ECWx.info/t/index.php

Offline dfroula

  • Forecaster
  • *****
  • Posts: 533
Re: My home-made ferrite antennas
« Reply #64 on: April 04, 2014, 10:00:14 AM »
The cotton idea should be fine. I used the "live rubber" Dubro sheets because I had some from building up a few RC planes. I think it's a good idea to wrap the shock-absorbing material around the entire length to avoid uneven pressures if the antenna is dropped or banged.

Likewise on the shielded microphone cable. I've had a spool sitting around for 15 years or so, so decided to use it.The direct wiring from the antenna magnet wire should be fine, if you are careful to scrape the enamel off the entire circumference of the wire ends. The 26 AWG makes good contact with the amp screw-down terminals without needing to solder on a thicker wire.

The resistance sounds about right.

At these frequencies, a few turns of magnet wire in the junction box should be fine. I've experienced no cross-coupling or other ill effects just stuffing the excess wire into the box.

Don

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #65 on: April 04, 2014, 11:18:05 AM »
Don,
thanks for the reassurance and clarifications.  Your really pioneering work and experience means a lot to those of us nervous nellies getting started.

Two other things came to mind. 

The document from Blitz indicated that (while they showed several rods they'd wound up) making your own was frowned upon and described as difficult.  Difficult is soldering the GPS module on and the winding of the cores was dumb easy.  Could even be done after some Cutty Sark was on board if needed (none needed here).

Second thing is how does one 'easily' remove the enamel off the wire?  For thicker magnet I have gently scraped with a blade, hoping to get only the enamel and not any copper.  The thinner is tougher to do.   Hams who wind their own inductors for old stuff say they can gently heat it off.  Others use fine sandpaper and grab the wire and pull the paper towards the end. Others have suggested dissolving it with acetone (in the correct non-flame, openly ventilated area).

With my #28 wire I want to be careful yet provide a good contact.

The proof is in the doing and what works, obviously.  Always looking for tricks.

Dale
ECWx.info
&
ECWx.info/t/index.php

Offline miraculon

  • Sunrise Side Weather
  • Forecaster
  • *****
  • Posts: 2876
  • KE8DAF
    • Sunrise Side Weather in Rogers City MI USA
Re: My home-made ferrite antennas
« Reply #66 on: April 04, 2014, 12:31:15 PM »
Don,
thanks for the reassurance and clarifications.  Your really pioneering work and experience means a lot to those of us nervous nellies getting started.

Two other things came to mind. 

The document from Blitz indicated that (while they showed several rods they'd wound up) making your own was frowned upon and described as difficult.  Difficult is soldering the GPS module on and the winding of the cores was dumb easy.  Could even be done after some Cutty Sark was on board if needed (none needed here).

Second thing is how does one 'easily' remove the enamel off the wire?  For thicker magnet I have gently scraped with a blade, hoping to get only the enamel and not any copper.  The thinner is tougher to do.   Hams who wind their own inductors for old stuff say they can gently heat it off.  Others use fine sandpaper and grab the wire and pull the paper towards the end. Others have suggested dissolving it with acetone (in the correct non-flame, openly ventilated area).

With my #28 wire I want to be careful yet provide a good contact.

The proof is in the doing and what works, obviously.  Always looking for tricks.

Dale

There is solder-stripping magnet wire. I have used it in the past. I see some available on eBay and other sources.

e.g.: http://www.ebay.com/itm/Magnet-Wire-40-AWG-Gauge-Enameled-Copper-2oz-155C-3990ft-Magnetic-Coil-Winding-/261087238074

Greg




Blitzortung Stations 668, 706 - CWOP CW4114 -  CoCoRaHS MI-PI-1

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #67 on: April 04, 2014, 03:30:03 PM »
The above links also leads you to a YouTube video showing how to strip the insulation off the magnet wire:

Personally, I either use my diagonal cutters or a piece of fine sandpaper. Either method is quick and easy. I always tin the wires after stripping it and prior to making the solder connections as it makes soldering a bit easier.
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline Silversword

  • --Stan Y.
  • Forecaster
  • *****
  • Posts: 428
    • Up Country Maui Weather
Re: My home-made ferrite antennas
« Reply #68 on: April 15, 2014, 05:55:06 PM »
Hi,

I started to construct (wind) my ferrite antennas while waiting for a part to come from Egon.

I had an issue with the heat shrink using the method previously described. Heated the ends first that worked toward the middle from both ends.  When I got to the middle somehow the heat shrink got between the center core and had a gap.  I did not glue each segment. Got frustrated with that method.  So I redid it by putting one core at a time and shrank one end but not going to the other end of the core.  Inserted the next core and used a small dowel that I had to push that core against the first one and proceeded to shrink over the butted area.  Went down the line using this technique for all six cores and got both of the 300 mm rods completed this way. No gluing or taping involved.

Next it is time to wrap it and another layer of shrink wrap session and put them in the PVC enclosure.

Regards,

--Stan Y.
   KH6HHG
   Maui, Hawaii


Stan Y. - KH6HHG - Maui, Hawaii --- Blitzortung ID: 993 --- FlightRadar24 ID: F-PHOG1
Weather Display 10.37s Build 42
WDL 6.05
MS Windows 7 Pro
Dell Optiplex GX280-Intel Pentium 4 CPU 3.00GHz, 4 GB RAM
Davis Vantage Pro 2+ Wireless
1-Wire Lighting
Webcam: Axis 211

Offline corwyyn

  • Forecaster
  • *****
  • Posts: 328
  • Far, far east Mesa, AZ
    • Sleeping Saguaros Weather  Mesa, AZ
Re: My home-made ferrite antennas
« Reply #69 on: April 16, 2014, 08:02:55 AM »
Stan, I had a similar problem when I tried to shrink-wrap some loose cores for one of my antennas, luckily I had plenty of tubing left so I removed the bungled tubing and tried again only this time I made sure to press in on the end cores so that I knew they were all seated against each other.  After that it went together nice and snug with no gaps.  The other antenna I glued the cores together and put them in the shrink tube, that one was easy to get finished.  Now I've got one finished with a bunch of turns of 24ga wire and I plan on getting the next one done this coming weekend after my hands recover :D  Hopefully I'll also get some time to start on building the boards.
Kevin
AD5VG
Blitzortung station 1042

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #70 on: April 16, 2014, 08:52:38 AM »
I was tempted to shrink wrap from one end only, but then thought about loosing out on the compressive effect that the tubing has as it slightly shrinks end to end, of which there is little.

I ran into a trapped air bubble in the middle.  The darn stuff was so tight against the ends that as I approached the middle, there wasn't enough leakage around the two end cores to let the air out.  A slight slice in the bubble in the middle and it came together very well.  The 2 mm or so puncture 'healed' with the shrinking much to my relief.

I just finished the amplifier board yesterday.  Very enjoyable AFTER I got a soldering tip and iron that allowed me to make good contact.  Even in this 100,000 population town, the only irons I could find were are Radio Shack and they looked like they were sized to do plumbing.

The controller board is slated to start today if I can get home from work early enough. I'm still worried about the GPS chip, but the rest of it should be a piece of cake with the experience I learned from the first board.

Sorry to dribble on about the lessons learned, but really bright light helps, and I appropriated my wife's stitchery ring light with magnifying lens in the middle to help out, even with illumination while a high power set of reading glasses (I did find some 3.5 diopter) and a head mounted stereo pair of lenses gave me more confidence.

The surface mount chips went surprisingly well.  I understand that for someone doing a lot of recent soldering, it would be no problem.  But, because of the access to the board without other components nearby necessitating the SMD installation right away, it means you are learning your soldering skills of years past on the most touchy part, with no recent experience or confidence.  I almost, almost, look forward to doing the next System Blue evolution board, or whatever it will be called.  Sort of fun.

The hardest thing to do, the micro USB connector.  The part in my kit had solder leads barely to the surface of the back side of the board, and to get heat to those pins and not just form a solder blob in the micro hole was a bit tough.  I wish the would have been a wee bit longer and stuck up through the board to have a physical contact with my iron to heat it.

But, to my delight, surprise and relief, at 10:30 last night after numerous rechecks under the bright light and magnification, I plugged it in and lights blinked, the reset button worked and I could vary the number of yellow LEDs lit by moving the potentiometer.

Oh, a plug for the step by step instructions that have been provided by another member, and I sincerely apologize for not having those notes with me as I type this; I cannot say enough about how WONDERFUL that effort is for the construction of these boards!  A difficult document to produce, and so far has been flawless, a great hand holder, and for those of us cautious and a little worried, it has been a great boon to my organization, making sure that things go on in the right order and no missteps along the way.  Marvelous.  A fantastic contribution to the project, and I'm sure that those who may choose to not embark on setting up their own station would do well and finish with this document. That said, if you've never soldered nor have the space to set up a work area to do this assembly with proper light and magnification, you still might see if there is a youthful pair of eyes connected to a body that works on electronics and all, to help you with this.

And, get a very nice pair of flush cutting, side style (CG Electronics has a nice one for about $5) nippers to take the leads off after soldering.

Can you tell I'm excited?  Go, builders!

ECWx.info
&
ECWx.info/t/index.php

Offline Cutty Sark Sailor

  • WxElement panel
  • Forecaster
  • *****
  • Posts: 2780
    • Frankfort Weather - TwinHollies WeatherCenter
Re: My home-made ferrite antennas
« Reply #71 on: April 16, 2014, 09:15:42 AM »
Well Done and Well Said, Dale!
Here's another quick tip, that I used for those 'multiple' "polarized" components, like diodes: Clip a short bit off each anode lead before inserting... the shorter lead adds another 'double check' for proper insertion...

...and one secret to getting the rods tightly together with the shrink wrap is to gradually and gently alternate each end, use lower heat setting if available, to about 'half-shrink' and not complete the end shrinking until you've gradually alternated toward the center from each end to the same 'half-shrink'... then follow the same process, ends first, alternating to the center to full shrink... if you follow me.

Mike

CoCoRaHS KY-FR-1  CWOP DW5536

       Blitzortung
       689
& 1439

sferics.us

 


Offline corwyyn

  • Forecaster
  • *****
  • Posts: 328
  • Far, far east Mesa, AZ
    • Sleeping Saguaros Weather  Mesa, AZ
Re: My home-made ferrite antennas
« Reply #72 on: April 16, 2014, 05:49:32 PM »
...and one secret to getting the rods tightly together with the shrink wrap is to gradually and gently alternate each end...
Yes that's what I did Mike, worked quite well.  Hopefully I'll get the other antenna wrapped this next weekend (man twisting all that wire around those small diameter ferrites made my hands cry :( )
Kevin
AD5VG
Blitzortung station 1042

Offline W3DRM

  • Forecaster
  • *****
  • Posts: 3192
    • Carson Valley Weather
Re: My home-made ferrite antennas
« Reply #73 on: April 16, 2014, 10:09:01 PM »
Great suggestions by everyone!

I finally spend a couple of hours this afternoon building my 300mm x 7.5mm ferrite core antennas. With the great guidance from above, I completed both of them in less than two hours (and two beers along the way  \:D/). They are now on-line, although sitting in my noisy office and seem to be working nicely.

I did do a couple things that may make it easier for someone else building their ferrite antennas.
  • Created a winding table so I could check-off the turns as I went along (Excel spreadsheet attached)
  • Built a small stand out of 2x4's and a 1/2" dowel to hold the 26AWS wire spool
  • Took numerous breaks (my back was killing me)
  • Had a couple beers to alleviate the pain above...  :roll:
  • Almost forgot - I tied a small knot in the wire coming off the base of the core. This was done to help identify which wire is to go to the input (not ground). As indicated in the instructions, the loosely wrapped lead is the one that goes to ground.
  • I tested polarities by placing both antennas parallel to each other. The signals observed were in sync which indicated I had wired them correctly.

NOTE: I was not able to get 725 turns on my cores. I managed to get 675 on both cores. The measured resistance of the windings for both cores reads at 2.6 ohms.

I'll add some photos I took of my setup later.

EDIT: Forgot to add that they have not been inserted into the pvc piping as yet. Once I do that, I will also shield them.
« Last Edit: April 16, 2014, 10:45:46 PM by W3DRM »
Don - W3DRM - Minden, Nevada --- Blitzortung ID: 808 --- FlightRadar24 ID: F-KRNO2
Davis Wireless VP2, WD 10.37S-b53,
StartWatch, VirtualVP, VPLive, , Win10 Pro
--- Logitech HD Pro C920 webcam
--- RIPE Atlas Probe - 32849

Offline DaleReid

  • Forecaster
  • *****
  • Posts: 1194
    • Weather at Eau Claire, WI
Re: My home-made ferrite antennas
« Reply #74 on: April 17, 2014, 07:57:52 AM »
Don,
Nice.

I'm looking forward to the pictures.

Once they are in the PVC holders/protectors, you said you'll shield them.

As I have read and reread the stuff to make sure to avoid as many mistakes as I can, I see that the official documentation from Eron says that ferrites may not need shielding and to try them without.  Plus I see comments here from others that they've been able to get good results without shielding. 

I'd be interested in your results if you try them in their expected final location to see if they are going to require shielding or not.  I hope you try it before you just go ahead with that part of the antenna construction to see how they work naked....

Dale
 
PS  If I used two beers I would have had no clue how many turns I had on the core.  I guess I'm a cheap date.

I just filled the cores from top to bottom with turns and hope for the best.
Dale
ECWx.info
&
ECWx.info/t/index.php