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I was enormously pleased to see a new post from my fellow blogger Roger, G3XBM Roger is recovering from a severe stroke and  facing difficulties I can only imagine. I’m sure I’m not the only one missing his posts about QRP projects nd accounts of his low power activities. Get well soon, Roger.

@G4ILO is on Twitter!  You can follow me from the widget in the left hand column of the blog.

My  Nevada WH3080 weather station has turned out to be a five minute wonder. Barely 3 months since we installed it, it has quit working. The base unit is no longer receiving information from the sensors.

There was a slight lift on 6m this afternoon, enabling me to try out my latest acquisition: an Elecraft PR6-10 preamp for the K3. A few days ago I noticed that the KX3 had a more sensitive receiver than the K3 on 6m. I couldn’t allow my K3 to be outshone by its baby brother so the preamp was ordered. I felt that the K3 could do with a boost on some of the lower bands as well so I opted for the new PR6-10 dual band preamp which despite the name covers the range from 6m to 12m. It was obtained and delivered to me very speedily by Elecraft’s UK agents Waters and Stanton. This was one Elecraft item that actually worked out cheaper to buy from the UK!

The preamp was very easy to install. It is designed to fit on the back of the K3 using the BNC connectors for RX IN and RX OUT provided by the KXV3A board. The preamp’s connectors are exactly the same distance apart as the ones on the K3 so you just need a pair of BNC couplers which Elecraft thoughtfully provided. I saw from the manual that the preamp was installed like this but I was afraid I would not have enough distance between the back of the K3 and the wall so I had ordered a couple of BNC patch leads as a precaution. In the end they weren’t needed.

Elecraft also provided a made-up cable to link the preamp to the K3’s switched 12V output and its ACC socket so you can select the bands the preamp is enabled for. On other bands a pair of pass-through connectors are enabled. This was the main factor for choosing the ready-made Elecraft preamp instead of a cheaper home-brew one as it meant I didn’t lose the use of the RX IN and RX OUT sockets that are utilized by the MFJ noise cancelling unit which is essential here on the 20m band.

Installing the preamp involved dismantling the entire station.

Although fitting the preamp to the K3 was easy, getting access to the back of the transceiver was not, and entailed the dismantling of almost the entire G4ILO station. Taking it apart may have been one thing, but putting it all together again is another. Labels fell off disconnected cables, other cables disappeared down the back of the table and had to be fished out again. If that wasn’t enough, the meter illumination lamp in the MFJ magnetic loop control box chose this moment to fail, resulting in a lot of time wasted after I had reconnected it trying to find out what I had done with its power supply.

Despite these hassles, installing the PR6-10 was worth the trouble, producing a clearly audible improvement in signal to noise ratio even on 12m. I can now hear stations that can’t hear me!

One of the things I’ve been up to the last few weeks is testing a new Bluetooth TNC made by Rob WX9O who is selling them as Mobilinkd. I had to put testing on hold while my Motorola smartphone went away to be repaired (by BuzzBox whom I can recommend highly.) In the meantime word got round and Rob sold out of these gadgets before I could write about it.

The price was around $49.95 which I thought at the time was amazingly cheap and probably explains why they are all sold out at the time of writing. The module is a small PCB slightly smaller than a Baofeng UV-3R and if you remove the belt clip it can easily be fixed to the back of it. My picture shows it strapped to the back of one of the Baofeng’s predecessors, where it makes a nice inexpensive and compact APRS tracker. The board and it’s battery (which can be charged using a USB cable as shown in the photo) are shrink-wrapped in a tough translucent plastic casing.

Ready-made cables are available. Rob sent me a Kenwood-format two-pin connector which fits the later model Baofengs and the two worked together perfectly. The audio levels were just right on both transmit and receive.

Yes, receive. This is no mere tracker. It’s a full KISS TNC and decoded all the packets received by the Baofeng. The software used was the latest APRSDroid running on my Motorola Milestone (a.k.a. Droid) smartphone.  Droid and TNC paired easily and made an effective APRS mobile station.

I did try to pair up the TNC with APRSISCE on an HTC Touch Pro running Windows Mobile 6.1. The two devices paired but could not connect as the Bluetooth software did not recognize the TNC as a valid device type. I think that is a limitation of the Windows Mobile Bluetooth software rather than the TNC module.

If you are interested in APRS and would prefer to do it over the radio rather than a cellular data connection (real hams use RF, right?) then this is a nice toy to play with.

They say that to err is human, to really foul things up you need a computer. And I have been fouling a lot of things up recently. The latest thing that I fouled up is the G4ILO’s Shack visitors book.

On the site I also have a contact log. This runs from a backup of my KComm (MixW format) log file. KComm automatically backs up my log to the web server, in order to create an off-site backup of my log. As a bonus, I have a PHP script that reads this backup file and displays the contents in a human-readable format.

What I stupidly did, when re-configuring KComm after my computer troubles a couple of weeks ago, was put the guest book file name log.dat for the backup file name, instead of what it should have been: g4ilo.log. So when KComm uploaded my contact log backup it overwrote the guest book data file instead. I only discovered this after wondering why the contact log on the site wasn’t updating.

I looked back in the site backups maintained by the hosting service but they only go back a couple of weeks.  I must have made the error before then. All I have managed to salvage is the most recent 3 entries. I’m rather upset about that, because the guest book contained comments made over many years from the early days of the site, which I had painstakingly preserved over various versions of guest book script.

At least I didn’t lose my contact log going back to 2001. That would have been a disaster!

There was a good opening on 6m this morning which lasted until early afternoon. I’d just been reading some list traffic on how good the KX3 receiver is so I thought I would plug it in to the antenna and see what I could do. After all, Six is the magic band, who needs 100 watts?

Listening on the two receivers was like night and day. On the KX3 the band sounded much more lively. Stations that were only peaking an S7 on the K3 were S9 plus.

On the KX3 with just 10 watts, just because a station was loud it didn’t mean I could work them. I got some 59 reports but with several stations they didn’t hear me even if I had no competition. The loudest stations had a lot of callers and they just didn’t hear me over the crowd. You wouldn’t think 9dB would make all that much difference but it does!

I’ve seen comments about the K3 being deaf on 6m, or even 10m, but I had never really bothered about it until now. If I can hear them on the K3 I can usually work them even though I generally limit the power to 80 watts.

But I ended up a bit dissatisfied with the K3’s receive performance on one of my favourite bands. The simple solution – fit a preamp between RX IN and RX OUT – isn’t an option for me as I need those ports to plumb in the MFJ noise cancelling device. It’s a pity no-one has come up with a mod to boost the K3’s fairly useless internal preamp on 50MHz.