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It’s annual general meeting time again for the Ridgeway Repeater Group (http://www.rrg.org.uk). The group looks after the GB3WH and GB3TD as well MB7UR and GB3NW in the Swindon area.If you are close by, do come along – it would be great to see you there.The meeting will be held at 19:30 at Thring Townsend, 6 Drakes Meadow, Penny Lane, Swindon. SN3 3LL
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We are very pleased to announce the winner of
1,000 Photo QSL Cards
from KB3IFH

Thanks to Randy for sponsoring this month’s drawing.
We had almost 500 entries!

We’re giving away more great prizes soon.
Stay tuned and get ready to enter.

OK, onto what you’ve all been waiting for!

The winner of our May 2011 prize giveaway is…

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Series Four Episode Ten of the ICQ Podcast has been released. News Stories include :-

• Amateur Radio suffers robot interference setback 
• Disappointment when poorly designed equipment malfunctions 
• 1000 FUNcube group members 
• Radio Hams' Royal Wedding Tribute 
• Practical Introduction to Amateur Radio
• World Amateur Radio Day on prime-time TV 
• Your Callsign to Mars 
• Easy Soldering Comic Book
• New 2m ham radio station on ISS 
• Danny’s Digital Packet 
• Bell System Technical Journals online
• One Millionth QSO mark for Summits on the Air

Your feedback and Martin (M1MRB) discusses NVIS.

Series Four Episode Ten of the ICQ Podcast has been released. News Stories include :-

• Amateur Radio suffers robot interference setback 
• Disappointment when poorly designed equipment malfunctions 
• 1000 FUNcube group members 
• Radio Hams' Royal Wedding Tribute 
• Practical Introduction to Amateur Radio
• World Amateur Radio Day on prime-time TV 
• Your Callsign to Mars 
• Easy Soldering Comic Book
• New 2m ham radio station on ISS 
• Danny’s Digital Packet 
• Bell System Technical Journals online
• One Millionth QSO mark for Summits on the Air

Your feedback and Martin (M1MRB) discusses NVIS.

See original post here.  Convinced that I had it working, I put the IC-290A aside and worked on some other projects.  But, when I came back to it a few weeks later, the display was still disappearing.  So, armed with the schematic and the block diagram, I began narrowing it down.

The display digits and tuning A/D converter are both driven off the same bus.  But, since the disappearance of the display did not bring loss of receive, that gave me some confidence that it was not affecting the synthesizer.  In order to simplify the analysis, I elected to assume that it was a single component (almost certainly a cold solder joint or an electrolytic capacitor) at fault.

Another clue was that the VFO dial ceased to operate once the display started acting up.  Taking the single-point-of-failure assumption into account, this strongly implicated the microprocessor on the LOGIC board as a starting point.  The only suspicious device that I could find on the schematic was C9, a 1000-uF, 6.3-volt electrolytic capacitor on the Vcc line of the microprocessor.  So, I replaced it with a similar value unit from my junk box.

And, the radio seems to be working…for now.   I did park it on WA1ZMS/B overnight and it is still running.

The iHAB-4 launch last Saturday was oddly enough close enough to my QTH (51 miles away– in Oxford, IA just east of Iowa City, IA) to justify taking the kids to.  It also happened to be sponsored by the Marion Home School Assistance program (Marion, IA) that my children happened to be open enrolled in. Yes, on top of everything else (having four, young, non-genetically related South Korean adoptees) we homeschool our children.

This was a great way of trying to interest kids in Amateur Radio. I’ve been taking my oldest two boys (9 and 10) to a Technician Class with the hopes that eventually between that class and me teaching them the material that at least one of them would get a Technician license. Yes, they are a little young, but I think they could do it. (After all, they are homeschooled.)   Unfortunately, they have been very antsy.. I think I will get at least one to pass.. but maybe that will take months more.. maybe years more?

They like hamfests… but they LOVED this launch…

It is difficult to keep kids interested in DXing, Contesting, building antennas, etc. But launching a balloon is a different story.

This should remind us all that Amateur Radio is a very diverse hobby with many aspects. Marshall Dias, W0OTM of Ottumwa, IA I believe became a ham to fly the types of communications payloads that he does fly on the iHAB missions.

You can see what this leads to:

Serious hardware for the balloon experiments

And, you can see a “Serious ham’s” equipment inside of the trailer:

Inside of the iHAB Communications Trailer

Of course, the payload boxes are even more interesting than the trailer.  Again, this shows how serious even this unusual aspect of the hobby can be technically!

iHAB-4 Top most payload - APRS 2m Beacon and 20m CW Beacon

As you can tell, Marshall W0OTM is an extremely positive guy and one could genuinely tell he enjoyed the involvement of the children.  My kids, with the important task of keeping the payload boxes from blowing away in the 25 MPH (with gusts over 30) Iowa nasty spring winds we thrilled to have the task.

The picture above showed my 9 year old son helping steady the top payload from blowing away.. the picture below shows my 10 year old (yes he’s shorter and smaller) doing the same with the bottom payload.  One of the experiments on this launch were separating the two payloads and running the antennas vertical between the two payloads.  It was probably a success on 20m, but it proved to be a bad idea on the parrot repeater (and maybe the APRS?) because when the balloon was above about 10,000 ft. the stations on the ground in Iowa were in the antennas deep null!

The payloads are a clever version of simple technology:  Here is an example:

iHAB-4 20m CW Beacon inside the payload box

The equipment inside the payload is decidedly low-tech.  I actually decided to show the 20m beacon as it is probably the most custom piece of hardware in the whole balloon.  The repeaters and APRS transmitters are literally Alinco small Handi-Talkies.

Marshall is not an electrical engineer.  He’s willing to fly payloads that the ham community provides.  (So build something for him!)  Personally, if I had time (which I don’t) I’d like to do a SDR ARISSat-1 style linear transponder with the APRS beacon as the transponder beacon.  Marshall also said that he has most or all of the equipment to do a crossband FM repeater.  But he believes the “parrot” repeater is more accessible to hams.  I think it’s rather awkward to operate through.  Maybe the community can convince him not to fear 70cm.  I worked the parrot repeater with a $99 TYT dual band HT.  Dual band FM rigs are cheap now!

The main point, though is the science and the “WOW!” factor of the event for the kids.  Actually the iHAB-4 launch was probably the least technically successful launches that he did– really.. almost nothing on it worked fully correctly!  But the specific involvement of the children on this launch made the event really special.  Marshall, W0OTM should be lauded for his willingness to cooperate with the homeschool assistance program and his utter excitement and positive energy was an inspiration to my kids– and all of the kids at the event.

He also reminded me, now 25 years into the hobby and — even though I am only 42 years old– I am definitely a curmudgeon and a OF…   the excitement I had early in my ham radio experience.  I suppose I need to try to recapture some of that.

The event was covered by the local newspaper (the Cedar Rapids Gazette) and their associated TV station KCRG-TV (Channel 9) in Cedar Rapids.  So there was very good positive advertising for the hobby with this event.

KCRG-TV 9 report on iHAB-4 launch — video on You Tube

Yes, my children and I seriously get our 15 seconds of fame here.

There are a lot of primary source info about this event on the http://www.ihabproject.com website at the following link:  http://www.ihabproject.com/iHAB-4/

Of course who are these goofy people posed by the fully inflated and ready to go:

The Motley Balloon Observation crewe

4/6 of the Spinner clan.  My youngest son and my wife stayed home to be the remote “mission control” for us!

Only a few days after I had ordered the little Jin Ma Tong JMT-227 145MHz transceiver from China, news began to appear of a new miniature Chinese transceiver from Vero Telecom called the UV-3R which was a dual band (136-174 and 400-470MHz) transceiver. Eventually these began to appear from eBay sellers under the Chinese brand name Baofeng. The price was an astonishing £25 plus postage from Hong Kong. I ordered one from the seller hk360radio and it arrived in just over a week.

The Baofeng UV-3R comes in a colourfully printed box. Together with the radio the box contains the battery (Li-ion 3.7V 1500mAH), a charger with two-pin socket and adapter for UK mains sockets, two antennas (one for VHF and one for UHF), an earpiece/microphone similar to a mobile phone hands-free kit and a manual written completely in mostly pretty good English. There is also a blue carrying strap carrying the seller’s name which is so cheap and nasty it is unlikely anyone would use it.

Not mentioned in the manual’s list of included accessories but also supplied was a cradle that can hold the radio while charging the battery externally. Why you should wish to do this when you can charge the battery installed in the radio I have no idea. There are no charging contacts on the radio, you have to charge it by inserting the small barrel connector into the socket in the side or by taking the battery out. There is also a short cable with one of these barrel connectors on each end, the purpose of which no-one figured out yet.

The UV-3R makes the JMT-227 look a quality product. This is the first new electronic product I’ve had that didn’t come with a peel-off protective film over the display. The plastic casing is extremely thin and the plastic belt clip that can optionally be attached looks as if it would easily break. To be fair, the flimsiness of the Baofeng may not be due to cheapness but to save weight. The radio is extremely small and very light, just 125 grams (5 oz) with battery inserted and antenna attached.

The provision of two separate antennas for VHF and UHF may be a cost saving measure or it may be for efficiency reasons (a single band antenna is usually more efficient.) However it is not convenient for a user who wishes to make regular use of both bands. The antenna connector is an SMA female, as used by all the Japanese ham radio manufacturers. Frequent changing of the antenna will result in wear of the connector and ultimately a poor contact as the centre pin of the antenna rotates in the socket. Some eBay sellers are now supplying this radio with a single, dual-band antenna. This is something to look out for when buying.

I had originally intended fitting an SMA to BNC adapter to the Baofeng as I have with all my other handheld radios but the UV-3R is so small and light that it seems inappropriate. I doubt that the radio is ruggedly enough constructed to take the stress of using one of the larger BNC antennas in any case.

Confusingly, the rotary switch on top of the radio must be pulled up before it can be rotated. Once you have realized that, the UV-3R is easy to use and easy to program the simplex channels and local repeaters into the memories by hand. There is free programming software available on the web. Programming cables are becoming available to buy on eBay but it isn’t necessary to use the software, unlike with early models of the UV-3R which had very limited menus that did not allow the changing of things like step size or power level except through the programming software. (This is something to bear in mind if considering buying a used one.)

But this radio is evolving rapidly. The manual that came with mine describes 12 different menu settings but the radio actually has 18. Every setting you would want to change can now be set through the keypad. The settings are also stored in the memories – even the selected power level, so that I can have the radio use low power whenever I use it to communicate with my Echolink node. Perfect!

The one thing it does not seem to be possible to do without the software is to program cross-band splits, such as listen on UHF and transmit on VHF. This could be useful for working FM satellites. But I am not very bothered about this.

All the usual RX and TX tones are supported for repeater access. A 1750Hz tone burst is generated by pressing PTT + VOL. The radio also receives Band 2 FM. The quality is not very good, but on the plus side FM reception is interrupted if a signal is received on the currently selected amateur frequency.

The performance of the little radio seemed to be well within spec. On a fully charged battery the output power on 2m was 3W on my QRP power meter. On low power it was 400mW. The sensitivity is also excellent. The box and some advertisements claim the UV-3R uses DSP. As no schematic is available I have no idea. All I can say is that the received audio is very clear and pleasant and that the signal to noise ratio receiving a distant repeater on the UV-3R with its short VHF antenna was better than on the Kenwood TH-D72 with its dual band antenna standing in the same place.

Newer versions of the UV-3R including this one now have an S-meter on receive, though it works in coarse steps. I also checked the strong signal handling performance of the receiver the same way I did recently with my other hand-held transceivers. It was on a par with the VX-8GR and the JMT-227, at the poor end of the spectrum.

The transmitted audio is very good, if slightly lower in level than some of the ham rigs. One local said my audio sounded “just like my normal audio.” The LED on the front of  the radio is supposed to glow red on transmit and green when a signal is received. Mine does not glow red, although the S-meter goes full scale to indicate power out. This appears to be a fault, but not one worth sending the radio back to Hong Kong to fix. However, this perhaps tells us something about the level of quality control you can expect for this price.

I have recorded an audio sample off-air, together with one of the Kenwood TH-D72 for comparison:

• Baofeng UV-3R using built-in microphone
• Kenwood TH-D72 using built-in microphone

The earpiece/hands-free mic supplied with the radio is not useful. I had some trouble with the audio but the main problem is that after you press PTT the radio locks in transmit. This appears to be due to RF feedback into the earpiece/mic cable as it doesn’t happen on the low power setting.

Using the supplied VHF antenna I can access from indoors a repeater 50 miles away. Not bad for such a tiny radio running 2 – 3 watts. Several people who have bought the UV-3R have commented favourably on the performance of the supplied single-band antennas. I tested the VHF antenna and found an extremely sharp response curve with a perfect 1:1 SWR at about 143.5MHz. At 145MHz the SWR was 1.5:1. The antenna has a high Q which no doubt accounts for its surprisingly good performance for its size. It’s a pity the resonant point isn’t exactly on 145MHz but that would be difficult to achieve with a mass produced antenna.

It isn’t perfect, but all in all I am pleased with the tiny little Baofeng UV-3R – for the price. However there are indications that where quality is concerned you are getting what you pay for. If I was a UK dealer thinking of importing a batch to sell I’d think twice. I think fussy British consumers would send quite a few back because of niggling faults like the non-working TX indicator or the problem with the headset/mic. But if you don’t mind taking a bit of a gamble on buying a radio from Hong Kong then the UV-3R would be a good bet for £25.