Hear George Dobbs, G3RJV, Webcast

This via Ian, G3ZHI, via the HamRadioHelpGroup Yahoo Group. I’ve heard G3RJV talk at Dayton, and he is a very interesting speaker…..Dan

Hear a talk on QRP by Rev. George Dobbs, G3RJV. The talk was given on Sunday, 11th APRIL 2010 at the Enniskillen Amateur Radio Show, run by the Lough Erne Amateur Radio Club at the Share Holiday Village, Lisnaskea, Northern Ireland.

To view the talk,

  • go to www.batc.org.uk,
  • go to BATC TV streamer, then
  • go to film archive.

These webcasts are examples of the wide variety of services offered by BATC to the amateur radio community. These include an excellent magazine. New members are very welcome. Cyber membership, magazine by email, costs as little as £4.00 on-line. Membership gives individuals and clubs access to the BATC streamer allowing live webcasts from your shack or from a radio club display, talk or meeting.

The Michigan QRP Club is What the Hobby is All About

Saturday morning, I had the good fortune to have breakfast with members of the Michigan QRP Club.

I’d always meant to get to one of their monthly breakfasts (held the first Saturday of each month), but they normally take place in Flint, which is about an hour away. Only when they decided to hold one here in Ann Arbor did I actually make it. Now, I’m sorry I didn’t make one earlier. A great time was had by all.

One aspect of the breakfast that I enjoyed was the “show and tell.” One of the things that sets most QRPers apart is that they’re builders, and the breakfast gives them a chance to show off their handiwork. This Saturday, there was a fellow who had built a sideswiper key and another who brought in his end-fed, halfwave antenna tuner. A couple of other folks also brought in things they’d been working on, but I don’t remember them.

After eating, there was the “junk box swap.” Everyone brings stuff from their junk boxes to swap for stuff from others’ junk boxes. I brought some GE222 light bulbs that I doubt I’ll ever use, some relays, and a bunch of pots. In return, I got some crimp terminals, a bunch of 10 uF electrolytics, and a half dozen or so panel-mount BNC connectors. Everyone was very generous, and I felt a little guilty about leaving with more than I brought.

The Michigan QRP Club is what ham radio is all about. I had so much fun at breakfast that I joined the club! It’s only $10/year ($12 for new members for the first year), and that includes a quarterly newsletter. They also sponsor several CW sprints each year.

I’m looking forward to going to breakfast again sometime soon, meeting more members, and showing off some of my projects. If you’re in Michigan, you might want to consider joining, too.

CT2GQV’s Homebrew Blog

Ricardo, CT2GQV, writes the blog, The “Speaky” HF SSB transceiver and other homebrew projects. I found this blog because Ricardo linked to one of my blog posts.

I like it a lot. Ricardo is a hard-core homebrewer, and has posts on a number of projects including:

  • 0-500 Khz converter to 4 Mhz
  • 100 w dummy load
  • Attenuator
  • Batery tester
  • BFO for hf-radio
  • Digital modes interface
  • HF SWR meter
  • Noise generator for filter aligment
  • PCB helping hand
  • RF Probe
  • S9 signal generator

…and much more.

I’m adding it to my links list. It’s certainly worth reading.

First, Check the PC Board

ATX80 board showing defectsBuilding is a lot of fun. You can build your own stuff, or take advantage of the work done by other hams and build projects from the ham mags like QST or CQ. One of the advantages of building projects from magazines is that frequently someone has already designed a PC board for it.

Even so, make sure you check that PC board before you start soldering parts. A recent purchase shows why.

The image at right is a scan I made of a PC board that I purchased to make a little 80m transmitter for transmitter hunting. Last night, I gave it a visual inspection before beginning construction, and I’m glad I did. For one thing, I noticed several spots that hadn’t been etched properly. These are marked with a “*” on the scan.

Those defects would have been easily corrected with an X-Acto knife, but when I flipped the board over to inspect the component side of the board, I found that none of the legends matched the holes in the board. Upon further inspection, I determined that the image used to print the component layout had been inadvertently rotated 180 degrees.

I e-mailed the vendor late last night, and this morning when I checked my e-mail, I’d already gotten a reply. The vendor apologized for the error, and said he’d get a new board out to me as soon as he could make a new batch. What great customer service!

Soldering Difficult Connections

Almost three years ago, I blogged about splicing my 40m dipole back together. The problem was that the wire had corroded, and I just couldn’t solder it properly. This episode came to mind when I read the following e-mail by Chuck, W5USJ, to the qrp-l.org mailing list:

Not a new thing and came up recently — problems soldering oxidized wire like coax shield and connections that are bright nickel plated and so on.

I used to have the old type rosin flux used for soldering copper plumbing. It worked really well for difficult surfaces (used sparingly). But that’s no longer available in favor of fluxes that will work with lead-free solders.

What I found that works really well is something called NoKorode Regular Paste Flux made by Rectorseal. It’s designed for lead-free solder but seems to work well on just about any metal. On the label there is this note: “Non-aggressive paste flux. Works on copper, galvanized iron, lead, tinned steel and other metals.”

One particular problem I have is with the shield on RG-174, the silver plated stuff anyway. With regular solder, even with high heat the solder wouldn’t stick well and often the insulation melted to the point of damage.

I had prepared some 174 with a short pigtail of twisted shield.

With the NoKorode, I applied a really thin coating on the shield. Then when I applied the solder it completely wicked into the shield almost instantly with complete coverage. As the name suggests, it does not seem to be corrosive in any way.

On some RCA connectors with what looks like nickel plating, I lightly dipped the end of my solder into the paste. Then tinned the area around the holes for the connections. That worked great too when I attached the wires; it was much easier to make a proper connection. No where near as much time was needed to heat the joint to get the solder to stick to the bright nickel surface.

It doesn’t take much to do the job with this flux and used sparingly should be fine for soldering other than electronics circuits. I’m going to try it with some of the bright metal finish on connectors like PL-259s. The 1.7oz container that I bought should last a very long time.

Sounds like I need to go get some of this stuff. If you go to the Rectorseal website, you’ll find that they make a whole bunch of different fluxes for use in different situations.

UPDATE
I just got this update from W5USJ:

Got some replies asking where to find the flux I used. One mentioned a few times was ACE hardware. My source is a local hardware, plumbing supply, lumber yard, welding supply, mini-Walmart affiliated with no national chain. It’s located in the county seat city of Emory, population 1100, Rains County, population 11,000. Sort of a rural location you might say…8^)

Also, I’d expect some plumbing supply stores would handle the NoKorode brand. Oatey has a similar product and a much bigger name in the brand stores. But the NoKorode seemed like a better idea to me. So I haven’t tried the Oatey brand.

Where are the Ham Radio Hackers?

On the Ten-Tec Omni VII Yahoo Group, Bill, KZ3DX writes:

If I was 17 years-old I would be hacking I-phones and other items like George Hotz, the 17 year-old from New Jersey who was able to unlock the Apple I-phone so that it could be used on other cell service networks.

When I was his age, I was “hacking” dial telephones. Then one day the phone company showed up at my house. My parents were not impressed with my technical abilities.

This morning there is a story that George has just hacked the “un-hackable” Sony 3 Play Station. He says the hack was 95% software and 5% hardware.

A quick check of the modifications site run by that guy over in Denmark, shows that there are NO MODS for the Omni VII…interesting.

I just wonder how many strange and wonderful things can be done with those 36 buttons/switches on the front panel.

Can the O7 be made even better??

My question would be, “Why stop at pressing some buttons on the front panel”? Why doesn’t someone really hack the Omni VII and develop a completely new software package for it? Rigs like the Omni VII and the Elecraft K3 would seem to be perfect candidates for this kind of hacking.

Sure, there is an order of magnitude difference between a $300 iPod and a $3,000 radio, but we’re big boys, aren’t we? Besides, aside from overdriving the finals, what real damage can you do to the radio? It seems to me that even if you manage to screw up the software in the rig, you can get back to square one by simply re-loading the manufacturer’s software.

Ham radio operators have a long history of modifying their radios. Page through any stack of QSTs or CQ Magazines from the 1950s, 60s, and 70s, and you’ll find many articles describing modifications to the popular radios of the day. About the only thing hams do to their rigs today is to clip a diode to allow it to operate out-of-band.

What does it say about the technical capabilities of today’s hams that we haven’t yet done with our gear what some 17-year-old kid has done with the iPhone and the PlayStation? Why don’t we have any third-party software for Omni VII or the K3? I think if a manufacturer actually encouraged third-party software development, they’d quickly gain a following and make their brand even stronger, don’t you?

What Every Ham Should Have in the Shack

Previously, I blogged about what every ham should know how to do. On a related note, the HamRadioHelpGroup now has a thread on what every ham should have in the shack. This is actually a revival of an older thread; the original poster, Jean, W4TYU, is now an SK.

Jean wrote:

There are basic tools that a HAM needs:

  • small screwdrivers – both straight and phillips,
  • cheap set of jeweler’s screwdrivers for the very small screws in microphone plugs,
  • soldering iron- one pencil type and one heavy one,
  • resin (or rosin) core solder,
  • small pliers and diagonal cutters,
  • 6″ slip joint pliers,
  • sharp knife for cutting insulation
  • small scissors,
  • an inexpensive volt-ohm meter,
  • black electrical tape to waterproof outdoor connectors, etc., and
  • cable ties of various lengths.

Bill, AB9BC replied:

I’d add an SWR meter, and be sure to check that it’s appropriate for the bands you are using.

Tim, N9PUZ, adds:

  • A nice long tape measure to measure wire antennas, map out your yard, etc. I have one of those roll up style 250′ long ones that makes a lot of tasks easy. They don’t have to cost a fortune. Buy an inexpensive one at Harbor Freight or somewhere similar. You are going to use it a few times a year to play with antennas NOT try to earn a living with it.
  • Safety goggles. Wear them, don’t store them in your toolbox. You only have one set of eyes and a blob of hot solder, sliver of wire, or a metal filing or wood chip while cutting or drilling can really ruin your day.
  • A decent pair of wire strippers for wire up to about 12 ga. Yes, you can use a knife or carefully held side cutters (DON’T use your teeth) but a wire stripper will be so much easier. I like the style with fixed sizes rather than the adjustable ones. Any home center type store will have them.
  • A pair of “Vise-Grip” type adjustable, locking pliers. You can use them to
    hold coax connectors while soldering, etc. as well as all of the normal things you’d use them for.

I would add some kind of adjustable, bench power supply. This is NOT the supply you use to power your transceiver. If you have such a supply handy, you’ll find yourself more willing and able to play around with circuits. If you don’t have one, I guarantee that you won’t ever do any experimentation.

What else should every shack have? A selection of different fuses, perhaps? Different kinds of connectors and wire so that you can make up a cable when you need it?

Four State Kit Update

From Terry, WA0ITP via the qrp-l.org mailing list. I’m thinking about getting an HF Test Set myself:

With the Holiday season upon us, it seems appropriate to provide an update of the Four State’s kit status.

AAØZZ EZKeyer. These have been selling like Snow Cones in the Sahara. The first run sold out in less than a week and another run has been made. This is an ideal first time builder’s kit, and we have plenty on hand to fill your orders. Order from the EZKeyer Web page. They are being kitted and shipped by Rex Terry, N5KDO, Tulsa, OK. Thank you Rex!

VRX-1 DC Receiver. Another run was made recently so we have a substantial number of kits in inventory. This Manhattan kit builds quickly and performs very well. A Manhattan layout template is provided, insuring correct parts placement. This kit is an excellent first Manhattan project.

Clear Top Tins. Another large quantity has been purchased, so these are still available. Larger than an Aloids tin, they showcase your projects nicely, and they are a bargain priced. They are being shipped by Dennis Smith, W5VAF, Jonesboro, AR. Thank you Dennis!

Enhanced Manhattan Audio Amp. This is the ideal first Manhattan kit.We still have some of these left, and may make a 3rd run if demand. is sufficient.

SMT Dummy Load. This is the ideal first SMT kit. We still have some of these left, and may make a 2nd run if demand continues. These are being shipped by Dennis Smith, W5VAF, Jonesboro, AR. Thank you Dennis!

NS-40 Class E Transmitter. Our best selling kit to date. The 4th run has just been completed so we have plenty on hand. This is a perfect first kit. Low parts count, a very easy build, and works on power up.

HF Test Set. Many on hand and more are being kitted at the regional meetings in Seneca, MO. Many thanx to the Barney’s gang and Dave Bixler, WØCH, for handling the shipping.

More kits are in the planning stage, and will be announced asap.

As always all profit is applied to funding OzarkCon. Thank you all for supporting The Four State QRP Group, it is greatly appreciated.

Make: Tackles Learning Electronics

The publishers of Make: magazine have just come out with a book on the basics of electronics. You can download a sample of the book that include the table of contents, the index, and Chapter 1.

From what I could see I like it. Right off the bat, they have you build a little LED circuit consisting of a battery, potentiometer, and LED. With just those three components, they’re able to demonstrate the concepts of voltage, resistance and current, as well as teach you how to use a multimeter.

Read more

Parts is Parts

When I was looking for a plug to fit into a Yaesu charger that I inherited, I was referred to Part Express. The not only had the part, but a lot of other interesting stuff as well.

They mostly specialize in consumer electronics, but they carry a bunch of stuff that will be useful to ham radio operators. Their holiday flyer, for example, offers a variable temperature soldering iron for $12.00 and a 12V, 2A power supply for $12.00. Prices are good until January 4, 2010.

The second catalog I actually got a couple of months ago. It’s the catalog for Small Parts: The Hardware Store for Researchers and Developers. They claim to have over 100,000 products.

For example, they carry all different kinds of wire, including magnet wire (24 AWG, $16/lb.), stainless steel wire, and brass wire. The small flyer that they sent me also shows all different types of plastic, rubber, bearings, gears, belts, mesh, tubes, and fasteners. Very cool!