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Topics - gil

#341
Another CW kit! That's number seven  ::) What can I say, it's all fun to me. I was lucky to get that one, as it is no longer manufactured. I found an unbuilt kit on the Rock-Mite Yahoo group. The radio is a 40m CW transceiver with a VFO (allowing tuning the frequency) and an output of 2.5W. There is no built-in keyer. I already have a nice Hammond 1590C cast aluminum box for it. I don't know if I'll have enough space to put the batteries inside the box though, since I will be adding a few PCBs in there. If I can, I will use 11x1.2v rechargeable AA cells. I think the digital readout is pretty flat, so it might work. Not sure If I'll have space for the touch keyer as well? My hopes of including a battery indicator, SWR indicator and audio filter/amp plus speaker are just fantasy on my part I think. Something will have to stay out of the box. I think the audio filter/amp and speaker can go in a separate box, because of size, and the speaker holes are a risk for water infiltration. The SWR indicator could be part of a separate tuner box, which might be better at the antenna instead of in the box (less coax losses). I like the idea of having the batteries inside. I plan on using fairly watertight plugs (no audio jack with big holes!).

Tonight I completed about 75% of the circuit board.

Here are the options I want:
- Touch keyer.  http://www.cwtouchkeyer.com/P4.htm
- Digital display. http://qrpkits.com
- Rechargeable batteries.
- SWR indicator. http://qrpkits.com
- Voltage indicator, http://qrpkits.com
- Audio filter/amp. http://newenglandqrp.org/nescaf

I found a mod online about changing the value of C8 to increase the range, but I need to ask a few people about that to make sure. I will be using a ten-turn potentiometer for better precision.

The whole build will be posted here.

Gil.
#342
General Discussion / Contesters.
October 10, 2012, 11:22:47 PM
By the way... If you are a contester who likes to call non-stop on QRP frequencies, you're not welcome here. Don't sign-up, and don't come back.

Damn it i'm pissed off!

Gil.
#343
New To Radio / Propagation primer, great document!
October 10, 2012, 11:02:37 PM
Everything you wanted to know about propagation:

http://www.nonstopsystems.com/radio/article-radio-propagation-N4UFP.pdf

Gil.
#344
General Discussion / Your shack photo.
October 07, 2012, 07:06:09 PM
Hello,

Time to show off your installation  8)



I know, i need a new desk! But it has followed me through many moves and I am weirdly attached to it.  Visible on the right is my Elecraft K2 on top of my Icom IC-271A all mode 2m rig. I have never transmitted on the Icom, but I listen to local traffic. On the desk, right side, is my Ham-Key paddle. The Mac mini is running Fldigi.  On top of the K2 is an MFJ-921 VHF tuner. The weird tube thing visible between the radios and the lamp is a Slim Jim 2m antenna I made out of soldered copper tubing. Fountain pen aficionados will appreciate the Mont Blanc pen. The K2 power supply is a small Astron. You can all see that I do have an FCC license, taped to the blinds! Below the license, a list of local repeaters..

My antenna is a PAR end-fed dipole 40/20/10, which goes from ground level up to a tree branch 40ft. up. The K2 ATU tunes it on 80 and 30m, but I get RF back in my room...

Gil.
#345
Hello,

I thought this would be a good topic for beginners. I am not so sure myself about nets... Tonight i have the VHF rig on, and heard a regional net. Stations were signing-in, basically giving their call signs one by one and a "good evening." And that's it! The net closed, end of story. What is it good for, and how is the information gathered used? There has to be something else than just a roll call? How does this relate to emergency management? Why would anyone sign-in other than testing their radio?

I understand it is part of the NTS (National Traffic System), but they don't practice passing traffic.. Actually, I've never heard it happen. They even ask if there are any emergencies. Now, I would understand that on a maritime net on HF, but local VHF? They will NEVER have an emergency, so why ask? People grab the phone and call 911, not the Ham radio..

I haven't yet had a phone QSO, ever. I'm not sure I want or need to. So, it there any advantage of checking in a local VHF net?

Gil.
#346
Morse Code / K1OIK presents CW for the beginning ham.
October 05, 2012, 09:08:41 AM
#347
New To Radio / Go Small, Go Now!
October 03, 2012, 10:13:16 PM
Hello,

I remember reading about building sailboats and came upon the saying from a famous sailor: "Go Small, Go Now!"

It can be applied to many things in life, radio being one of them. Sure, you might want to save up for a $1000 transceiver... But if you recently got or will get your license soon, you really don't need one right now. Hell, a $139 CB can get you started, without the license. What I want to draw you attention on however is QRP (low power) radios. You don't need more than a few watts to make intercontinental contacts, believe me. You just need a decent antenna, which could be a simple wire up a tree.

If you want to start really small, then there is Morse code (CW mode). CW radios are very small and very cheap. The Rock-Mite kit for example costs $29 and can be built by anyone with decent soldering skill which can be learned in an hour. See http://smallwonderlabs.com. There are more complex kits like the Elecraft K1 (http://elecraft.com). TenTec right now has two-band CW radios for sale at $188 (http://tentec.com) as well as mono-band kits. Learning Morse code can be a lengthy and frustrating process but for someone on a budget it is unbeatable. Making a first Morse QSO is something anyone can be proud of, even if it was just exchanging call signs.

For phone (voice) operations, the choice is more limited when it comes to radios under $300. MFJ has a great line of SSB radios, the MFJ-94xx series. Here is my favorite: http://www.mfjenterprises.com/Product.php?productid=MFJ-9440X. It will do CW as well with an added module. 10W is plenty of power to work the whole World. If you like building, check out http://ozqrp.com and http://qrpkits.com. I have bought kits from both and can attest of their quality.



Believe me, putting more money in complicated radios will not make your signal go further or make you hear much better. You just get a ton of extra features which, however nice, are not needed to operate successfully. Don't even get me started about amplifiers... Band conditions and antennas are the main limiting factor, power comes third. From a prepping perspective, current draw and portability are very important factors, keep that in mind.

Go Small, Go QRP, Go Now!

Gil.
#348
Antennas / Rugged Antennas.
October 03, 2012, 09:12:50 PM
I have been working on something new... http://ruggedantennas.com

Does anyone know of a good numerically equipped machine shop?

Thanks,

Gil.
#349
Morse Code / Rock-Mite success!
September 27, 2012, 04:12:53 PM
Hello,

It doesn't take much power to make contact...

Yesterday I added a few inches of wire to my PAR End-Fed antenna, which got it centered on 7040kHz. This is ideal for my Rock-Mite, which is somewhere between 7029 and 7030. So I plugged in the little guy, which incidentally is my paddle base!

I am thus never without a backup radio. I started callind CQ but the keyer was lagging and ignoring some dits and dahs. That was the Pico Keyer chip. I replaced it with the original provided by Dave Benson in the kit and all was well. A few minutes later I was in a short QSO with a station 625 miles away, with 1W of power! My signal wasn't great, but he heard me.

Operating QRP (low power) isn't some kind of black art. It is about reducing losses. Most people who run 100W are not radiating 100W, 30 or 50 maybe, or even less.
In my opinion, 5W for CW and 10W for SSB is all one needs, assuming the antenna system is well designed and losses kept to a minimum.

Why would anyone want 100W, or even 1500, for heaven's sake, I don't know...

Gil.
#350
Antennas / Buddistick first impressions.
September 24, 2012, 07:14:54 PM
Hello,

I received my Buddistick antenna today, and decided to set-up a QRP station inside the house. I wasn't expecting much to happen mind you.. So, I got my Elecraft K1 out and clamped the Buddistick to the coffee table in the living room; second floor.. Set-up was very easy, especially using my "Tenna Dipper." Minutes later I was in a QSO with a station 800+ miles away! He gave me a 569 report, which really surprised me. I was putting out 6W. So, this one is going on my "do not ever sell" list. I will report any further unexpected QSOs with this antenna. Now I need to take it out into the wild and operate from some remote area...

Gil.
#351
Morse Code / My first QSO ever!
September 21, 2012, 11:37:54 PM
Well guys, I did it! My first QSO ever as a Ham was in Morse code. There was a contest going on on 40m, so it lasted less than a minute. My signal was picked up by F5IN in France! He replied with my call sign, I sent him my name, which he repeated. That's using 6W into a 66ft end-fed dipole strung around my house! I can't believe it, given the conditions..

Here is the guy's station, check out those antennas: http://f5in.pagesperso-orange.fr/cariboost2/

Gil.
#352
Hello,

Assuming a SHTF/WROL situation, when would people use their radios to get information on HF bands? At night? During the day? What about a party relocating on foot? There would be so much to do then and so much confusion, there might not be much time to even use a radio...

You guys who go hiking, packing a radio, when did you find yourself using it?
If you had to care more about safety, would that change your timing?

When on the move, I am assuming radio operations would have to be during periods of rest...
Would that be during the day, or at night?

Thanks.

Gil.
#353
Antennas / A magnetic loop antenna for 40/30/20m.
September 17, 2012, 02:38:11 AM
Sometimes trying to make an HF antenna fit into your backyard is like trying to make a size 14 woman fit into a size 8 dress... Some things are just not meant to be. Enters the magnetic loop. It's fairly small, decently efficient (I hope), and fairly easy to build. There is no free lunch, especially when it comes to the laws of physics, so something has to give. For one, they produce voltages and RF that will fry your pacemaker in a heartbeat (your last..). Bandwidth is as thin as an airplane sandwich and they require expensive high voltage variable capacitors, air type (if you're lucky), vacuum (if you're rich).

I decided to build one out of 1" copper tubing. It worked very well for my Slim Jim 2m antenna, so I have high hopes for the magnetic loop. Most of the information came from Frank (N4SPP), and I thank him profusely here for writing his excellent article: http://www.nonstopsystems.com/radio/frank_radio_antenna_magloop.htm. He even sent me screen shots of the RJELOOP1 software used to calculate all the loop parameters. I later was able to run it on my Mac using DOSBOX, a DOS emulator. The software was designed by the late Reg Edwards, UK Amateur Radio Station G4FGQ and can be found here: http://www.zerobeat.net/G4FGQ/page3.html.

I wondered how big I should make it. My requirements were only that it fits through a regular door frame and covers 40m. It just happens that a 6'3" tall loop works perfectly for 40/30/20m!

Here are the results:
40m:

30m:

20m:

Notice how efficiency improves when the loop is raised only a few feet (second floor..) 40m:


I will be feeding the loop through a FT-240-31 toroid, which I already have: Fair-Rite part number 2631803802: http://www.fair-rite.com/cgibin/catalog.pgm?THEONEPART=2631803802. The capacitor is an air type, 9-110pf 4KV (CAV 12-23): http://www.surplussales.com/Variables/AirVariables/AirVar1.html. It won't be as easy to tune as a multi-turn vacuum capacitor or take as much power, but I am not spending $250! It should arrive on Wednesday. Now I need to go to the hardware store!

I will be posting the whole build here, so stay tuned  :)

Gil.
#354
Antennas / Ground rods, how?
September 16, 2012, 10:09:32 PM
Hello,

How do you get those 8ft. copper rods into the ground? Dig a hole? Pound on them from the top?

Gil.
#355
New To Radio / General and Extra license manuals, free.
September 16, 2012, 03:50:48 PM
Hello,

I am giving away my General and Extra license manuals. You pay for shipping via Paypal.
Now, don't ask me to send them to you if you are not seriously studying for either exams.
I want to make sure these go to people who really need them.
You need to be a member of this forum. Contact me via forum private message.
Send me your address and Paypal email, I will send you a Paypal invoice for shipping.

Good luck!

Gil.
#356
Hello,

I found the MST400 on http://ozqrp.com. It is a nice single-band 40m LSB radio with a digital frequency display and a DDS VFO. It will be a nice backup to my K2 or something to take along with my K1 on hikes. The kit is partial only, with the hard to find components included. Everything else, you can find online. At $75+shipping, it is a cheap way to start on building your own radio. The circuit boards are of excellent quality and the manuals, downloadable, very easy to follow. I can't believe this kit isn't famous yet, but I think it is pretty new. I probably should have soldered the ICs at the end, but I couldn't resist...

It would be great if the kit had a built-in iambic keyer and 400Hz filter for CW, but oh well.. That's what the K1 is for..

#360
Digital Modes / Are digital modes practical for prepping?
September 09, 2012, 01:19:29 PM
I used to think that CW was the only practical data mode for preppers. I still think it is the most important one. There might be a place however for data modes in emergency situations. I am thinking of news bulletins and passing messages. ConfederateColonel got me thinking about this.. Some modes like Olivia can decode a message buried deep in the noise. You can't even hear anything but static, but the data comes through. These modes are amazing in that regard. With the abundance of sub-$300 laptops and the simplicity of connecting them to your radio via the earphone/microphone jacks, why not give it a try? A news bulletin can be typed, then cut-and-pasted into a program like fldigi. Some software will allow you to set your radio as a beacon and transmit the message at regular intervals. Even at QRP power, it will eventually go through... The biggest issue with digital modes is to agree on a standard. After reading about practically all of them, my vote goes to Olivia. I have yet to experiment though, so let's discuss possible modes and setups to achieve a practical solution.

Radio Preppers I hope will eventually end-up on the air. We won't call it that of course, it will just be another friendly net.. We could then practice voice, CW, and one data mode for our purpose. The main band will probably be 40m because some of it is accessible by all license levels and propagation works even in low solar activity. NVIS is possible as well for local contacts. 40m is the most versatile band in my opinion. The General exam is fairly easy..

For prepping purposes, I don't think it is a good thing to spread out to many bands and modes (except on receive). Having just a few "watering holes" would make it easier to find "like-minded" individuals, people who read this forum. Note that the goal here is not to form some kind of militia group. It is to exchange information on developing events between somewhat trusted individuals with whom we may have had prior contact and maybe even developed a friendship with.

So, do we need digital modes?

Gil.