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Conditoins remain excellent on the 10m band. I made several contacts and even had Stateside DX stations reply to my CQs. Two of my contacts were with Elecraft K3 users – don’t often hear K3s on digital though they are the perfect rig for it.

When I’m not actively working stations I like to look at the PSK Reporter reception reports map.  It’s more interesting than WSPR as the reports are of actual PSK31 signals. It’s a pity there isn’t a beacon mode because you have got to transmit or call CQ to see reports of your own signal. At least it is motivation to actually go on the air rather than just lurk!

There aren’t that many modifications that you can do to the Elecraft K3. This is very different from the K2 as in my list I now have 138 different modifications for it. But Elecraft does have a few K3 enhancements and mods on their home page and here are two additional modifications that I have done to my K3.

Plug-in roofing filters on main RX board

The first one is to add a wideband LC-filter (roofing filter). The filter was inspired by ideas from W5DHM with three tuned sections at the IF frequency of 8.215 kHz. It is to the right in the image. It is not the best of filters, and probably compromises performance somewhat, most likely because of its low image rejection 30 kHz away. It has however served me well as a receiver filter for the latest version of K1JT’s software WSJT-X. That software processes a 4 kHz band for both the JT65 and JT9 digital modes, and the LC-filter has demonstrated to me the utility of having a wide roofing filter for reception of those modes. The filter also works well for listening to broadcast AM which was what W5DHM designed it for in the first place.

Back panel of the K3

The second modification allows for a connection to the P3 Panadapter without using the recommended KXV3A Interface. All that is needed for the P3 is simply a minicoax with proper terminations. On the underside of the main PCB it should have a plug that connects to the J66 connector (see page 10 in the KXV3 manual). In the other end it is soldered to a BNC connector on the back of the K3. I put mine in the hole reserved for the REF input, as I don’t have the K3EXREF External Reference Input option. The BNC connector was marked with a label that says “IF out” as seen in the image.

Both of these modifications are temporary, and as a matter of fact the last one was just replaced by a KXV3A after several years of service. I needed the KXV3A for the PR6-10 preamplifier. I also plan some day to replace the wideband LC-filter with either the KFL3A-6K 6 kHz AM/ESSB filter or the KFL3B-FM 13 kHz FM filter.

I was fighting a high ambient noise level tonight, while participating in the monthly NAQCC Sprint. Not as terrible as it was a few years ago, when 40 Meters was so bad that I had to abandon the 40 Meter Fox Hunts, but bad enough to be annoying.

With the goofy damp weather we have been having, I think the local QRN was due more to atmospherics, than anything else. I’ll have to see how the band conditions are over the next few days.

In any event, I racked up 22 QSOs during the during the Sprint, almost evenly divided between 40 and 20 Meters. It ended up being 10 QSOs on 20 Meters and 12 on 40 Meters. Not my best effort, by any means, but not abysmal, either.

I was happy to work Jim W1PID at the very end, but was disappointed that I was not able to get a QSO in with my two NJ buddies, Don W2JEK, or Charles W2SH. They were both sitting on frequencies, running mini pileups, and I could just not break through.

Just goes to show you ….. sometimes you get the bear, and sometimes the bear gets you.

72 de Larry W2LJ
QRP – When you care to send the very least!

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!

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.

In my e-mail box was a special announcement from Elecraft. Today they announced they were taking orders for the KXPA100 amplifier for the KX3, and the KXAT100, the auto tuner for the amp.

The amp is $700 and the tuner is another $300.

At this point, I don’t think these are in the cards for me, for a couple of reasons.

1) Price – I just don’t have an extra thousand bucks laying around. Of course, I could always part ways with something, like my K3, but I’m not too crazy with that idea.  I bought it soon after my Mom passed, so it holds a lot of sentimental value.

2) Practicality – I like the idea of having two rigs. My K3 and my KX3 are mutual backups. If something were to happen to one, I still have the other. If I were to sell the K3 in order purchase the KXPA100 and the KXAT100, I would no longer have a backup. I also like having a main station rig and a dedicated portable rig.

3) Personal – I need to be happy with what I have and not always be on the lookout for “more”. I am very fortunate to have what I already own, and while it may be less than some, it’s still a lot more than even others. I need to enjoy what I have and get off the “consumer hamster wheel” of always wanting more.

72 de Larry W2LJ
QRP – When you care to send the very least!

I just finished a contact with a very loud Austrian station, OE3DIA on 10 metres, who took time out while working a string of stations to give me a complimentary audio report, quite unsolicited. It’s good when that happens! The comment was “Very nice audio cutting through the QRM” I was using the K3 at 80 watts and the mike was one of those Heil mikes with the dual insert, set to “narrow”. The K3 transmit audio equalisation is factory standard, in other words flat.

As it happens I had just been doing some audio comparisons between the KX3 and the FT-817. There has been a thread going on the KX3 Yahoo group started by a disenchanted American ham who claims that the FT-817 has punchier audio than the KX3. It’s rubbish, to put it politely. The KX3 has a built-in speech compressor, while my 817 has an RF processor made by Joachim, DF4ZS (more details on my FT-817 page) built into the microphone. Without it there is just no comparison.

I recorded some audio clips so you can hear for yourself:

• FT-817 with standard microphone, no compression
• FT-817 with standard microphone and DF4ZS compressor
• KX3 with MH3 microphone, mic gain and compression both set to 30

There is a bit of distortion on those clips which was not noticeable when listening on the radio. I think I might have a problem with my sound card.

I’m not sure if the difference are that noticeable in those clips, but when you look at the needle of the power meter the KX3 certainly has the more punchy signal.

Both the FT-817 and the KX3 were running off 13.8V and set to 5 watts output. I couldn’t compare them on battery power as I don’t have the charger board for the KX3 and the external battery pack (10xAA NiMH cells) I intended to use appears to be past it and the KX3 kept cutting out on voice peaks.