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I have been playing with using the Kenwood TH-D72 as a standalone digipeater and fired up the FoxTrak APRS tracker I built last year. The FoxTrak is a TinyTrak clone using DK7IN firmware. I had not noticed a problem before when using a TNC connected to PC software, but now I found that the D72 will not display the FoxTrak’s packets. Instead, it interrupts the frequency display and puts >F G4ILO-12 on the first line of the display. The packets are digipeated but they don’t appear in the radio’s list of received stations.

I’m guessing that >F is some sort of error status but it is not listed on page APRS-3 of the user manual where the other status indicators are listed. Does anyone know what it means, or how to configure the FoxTrak so that the Kenwood will display the beacons?

So I guess this video is as viral as you can get in the Ham Radio Community. But the name of the video lives up to what you see in it. I guess you could almost say it’s something you would see on HamSexy. But everyone has their own way. So here it is. The video that has been making it’s way around Twitter. Some questions I have about this video is, how does he know which mic to use, and how does he keep track of conversations? And what’s up with the business cards on the dash? And with all those speakers, does he get surround sound now if he tunes all the radios to the same frequency? Just askin’.

73.

Rich also writes a Tech blog and posts stories every Tuesday and Thursday on Q103, The Rock of Albany’s website, as well as Amateur Radio stories every Monday thru Friday here on AmiZed Studios.

Today I made a programming cable for the Baofeng UV-3R. Until now I couldn’t be bothered, as the radio is easy to program manually and neither the cost of sending off for a programming cable nor the complexity of building one of the programming interfaces published on the web seemed worthwhile. But it turned out to be very easy.

A few months ago, with other purposes in mind, I ordered on eBay two USB/TTL/RS232 cables. If you search eBay for “PL2303” you should find a couple of sellers: one from Hong Kong is currently selling a single cable with free shipping for £3.99. These are USB plugs with the serial converter built in to the plug. At the other end there are four wires: GND, TXD, RXD and +5V. The logic level is 3.3V (at least mine are) so it can be used directly with the UV-3R. Just solder the appropriate wires to a 4-way 3.5mm jack plug.

The connections (and the wire colours for my cables) are:

• GND (black) – base of the plug
• TXD (green) – first ring
• no connection – second ring
• RXD (white) tip

Cut off the red +5V wire and make sure it doesn’t short out against anything.

In the photo you’ll see that there is something else in the middle of my cable. That’s because I used a 4-way 3.5mm to mini-DIN adapter sold for use with various Yaesu radios such as the VX-1R, VX-3R, VX-5R, FT-60R and VX-150 instead of a simple plug. I bought that at the same time I bought the radio as I thought it might be useful if I wanted to try connecting other things such as a TNC. Plus the simple 4-way 3.5mm jack plugs are a bit hard to find.

Mini-DIN plugs can be a bugger to solder, especially with my hands shaking as they do now. But the inline socket I used today had terminals that would hold the tinned end of a thin wire pushed into it even without soldering, which made the job easy for me.

I tested the new cable with the UV-3R programming software and it worked, so that was a good result.

By the way, I saw on the UV-3R Yahoo group that the free cross-platform cross-radio programming tool CHIRP will soon be supporting the UV-3R. I can claim a little bit of credit for that as I was instrumental in persuading a UV-3R user who had been investigating the programming protocol to share his findings with CHIRP’s author. So soon you’ll be able to upload memories from other radios into your UV-3R.

K4UPG demonstrates how to get to FOBB in STYLE!

While everyone is thinking about antennas, staying cool and planning for the upcoming FOBB, I been checkin out a new ride! What do you think? Buzz- Buzz! Does this shout FOBB or what?

Now I can settle down and get ready for FOBB action with my untested top secret antenna. It will be all out for me again this year! Lookin’ for my friends out there on the ether and praying we don’t get lightning again like we did in 2009.

The last few years 20 meters has been the go to band, but it sure has not sounded very good here in Central Florida during the contest hours, so it will require being ready to shift bands to take advantage of the conditions.

BumbleBee #010 is gonna be listening for you all and lookin’ for the promised post of last year’s results too. CUL and 72– K4UPG

It has been yet another fabulous summer day here in Cumbria. I’m in good spirits and physically feeling fitter by the day. I think the balance issues and “jelly legs” are more an effect of the brain operation than a lack of fitness. Perhaps the same reason my hands often shake badly and cause frustration when trying to attempt soldering.

We decided to go for a walk over the fields to the north of Cockermouth and have a picnic lunch. I took the Taiwanese twins in the hope of making a few radio contacts whilst we were out.

The walk involved some gentle climbing up from the valley. On the way I heard Alan M1EYO/P call on 2m to activate the SOTA summit of Watch Hill G/LD-054 which is almost literally in my back yard. You can see it on the far left of the picture behind me. When I was fit I could walk to Watch Hill though I never did as there was not much attraction in walking for an hour and a half to reach the summit when I could park the car within 15 minutes walk of the top. With no car unfortunately even Watch Hill is out of bounds.

After I worked Alan we carried on walking until we almost reached the Carlisle road, where we found a grassy south facing slope to have lunch. This is probably the only portable site that I can reach on foot from here, though it isn’t a very good site as it is still within the Derwent valley or “Cockermouth black hole” as I call it.

Checking 2m from time to time with a 5/8 telescopic whip on the 2m radio I heard Richard G1JTD/P activating Illgill Head G/LD-029. With a bit of help from Tony G1OAE Richard heard me and we made a contact. I had to use the monitor button to disable the fixed squelch on the H112PLUS which is set far too high. The receiver on the 5/8 telescopic seemed quite poor possibly due to intermodulation or overload. These really are terrible radios!

Alan was going to activate Binsey G/LD-041 a favourite of mine which was in fact the last summit I activated so we waited until he called on 2m and I had another contact. Alan told me he had discovered Rob G4RQJ on the other side of Binsey summit working 40m and setting up to try 4m. I pricked up my ears at the mention of four metres and about a minute later I heard Rob calling on the other H112PLUS so I was able to make my second-ever contact on 70MHz. Binsey is also line of sight from where I was so it was not a DX contact but it was still nice to make a contact on the 4m band.

After that we packed up and walked home. It was a pretty tiring day’s outing for me, definitely the furthest I have walked and the highest I have climbed since my operation. But it was quite a morale booster to get out on such a nice day and do some portable operation. There are even some trees there I could try to get some wire over for some HF operation with the FT-817 in the future, so that’s something to look forward to.

As I mentioned previously, the receive capability in my 50-MHz transverter seemed to be a little bit anemic.  So, I decided to add a little bit of gain.  Looking at the block diagram for the transverter (shown below in updated form—jumper across the SGA-4586Z to understand what the circuit looked like initially—by the way, full-sized PDF versions of all of my notes and schematics will eventually be available here), I reasoned that I had the following losses and gains:  +10 dB for the LNA (this might be as much as +15 dB, but 10 seems more realistic, if not generous), -3 dB for the bandpass filter, -7 dB for the mixer conversion loss, and -3 dB in the diplexer, leaving me with -3 dB overall conversion gain.

So, I endeavored to find some more gain in the form of a MMIC (which is really what all gain blocks in this transverter would be if I were to do it again).  I have a nice (but dwindling) supply of SGA-4586Z’s that produce about 20 dB gain with a 1-dB compression point around 16 dBm, which is probably a good part for this location.  The idea is to overcome the losses in following stages with robust gain in earlier stages (in order to keep system NF low).  So, I ripped out the existing two-pole BPF and replaced it with this:

I was relatively satisfied that I had everything working with the cover of the transverter off to peak the BPF on the W3APL beacon.  So, I replaced the cover and surprise!  To borrow a poetic description of RF circuit doom from N3UM, the MMIC “amplifier burst into song.”  Bursting into song is a bit of a charitable description for something that sounded more  like S9 power line noise in the IF receiver.  I did not actually know that it was the MMIC oscillating at first, but I started wiggling cables and finally found that if I touched the 12RX (+13.8 volts on RX) line, the problem disappeared.  So, I added the 0.01-uF bypass capacitor to ground on the supply side of 180-ohm bias resistor and the problem was solved.

With the completion of the HF SoftRock with Si570 LO, I now have a tunable IF to play with the transverter.  We had a nice opening to the Southeast and Gulf this morning and I even heard my first DX with the transverter and SoftRock combination—CO2WF.  With the appropriate software, I can configure a the SoftRock as a panadapter with the TS-930S as the transmitter.  More on this in the future.  Best of friends:

The real next step in making the transverter useful is building a 20-watt PA stage.  This should be good for driving a Mirage or TE Systems brick or even something bigger like a 3CX800 or 50-volt solid-state amp…

Got the SoftRock v9.0 Lite+USB Xtall working last night.  I’m not 100% sure what the problem was, but I think it may have been due to me programming an ATTiny85 with the latest SoftRock firmware (V15.14), rather than using the supplied ATTiny45 with V15.4.  So, I’m sticking with old version for now.  Not sure if it was cockpit error on my part programming (more likely) or an incompatibility with the new firmware which is designed to work with the Ensemble series of SoftRocks.

As shown in the screenshot from Rocky above, there appears to be a spur that repeats every 1 kHz (see left side of the waterfall).  The right side of the waterfall is with the USB cable unplugged from the computer.  I’m 99% certain this is something internal to the SoftRock because I wrapped a few turns of the USB cable around a big type-31 ferrite toroid and the spurs are still there.  So, need to play with that.

I’m listening to a Es opening to the south on 50 MHz right now using the SoftRock as the RX IF.  Yes, that means that I got the RX on the transverter souped up a little hotter.  I will post something about that later today and place a non-causal link in this post.