Working SOTA stations

I have one of the rigs on S20 most of the time I'm in the shack listening for local FM contacts. Occasionally I hear operators calling CQ SOTA. I try to always reply to them as they have taken the time to climb up to the top of a high point. It must be really disappointing when nobody replies back to them so I encourage everybody who hears a CQ SOTA to please reply.

I was just speaking with Tom M1EYP stood upon SP15 "The Cloud" near Bosley, Macclesfield. He wanted other operators to also try reponding to him on 6m SSB. I of course am fully equipped for most bands and was able to just pick him out of the noise. He gave me a 59 response he was only 41 to 51.
On 2m FM he was 59 end stop.

I also send eQSL cards out too so they have proof of the 2 way contact should they need it for an activation. Tom was no exception and an eQSL is on its way.

Noisy 20m band and quiet 15m band

I normally work the 20 and 15m bands in the morning through into the late afternoon. Over the last few months this has been really lucrative being able to work many countries during the day. Over the last couple of days 20m has developed a lot of atmospheric noise and 15m has become fairly quiet.

I hope the bands will improve otherwise I'll have to go back to VHF/UHF for a while :(

Tuning out QRM on datamodes using the Yaesu FT-450D with DM-780 and Ham Radio Deluxe

The standard way of operating a datamode such as PSK-31 is to leave the filter width as wide as you can and tune to the operating frequency. The software, in my case Ham Radio Deluxe running the DM780 module, then uses software filters to narrow reception down to whatever audio frequency you have selected in the waterfall. This works well 99% of the time but you do get occasions in the middle of a QSO when a very strong station starts transmitting in an adjacent audio frequency. That station probably can't hear your contact so doesn't know that it is generating QRM.
This can sometimes result in swamping the signal coming from your contact.

The two useful filters on the FT-450D highlighted in yellow

The radio then comes to the rescue. From very early days it has been possible to engage IF filters, notch filters and such like on communications equipment. When somebody is tuning up close to your listening frequency engage your tunable notch filter. If somebody is transmitting on SSB a few KHz up then engage your IF Shift. The ways of getting rid of QRM are very wide ranging and easy to do.

Diamond V-2000 triband vertical review - a replacement for an older Diamond X-50 dual bander

My old Diamond X-50

The new Diamond V-2000 in situ
The 6m inverted V is pointing
east to Europe

Diamond X-50

As mentioned in a previous post my dual band colinear had suddenly gone deaf. When taken down it was found to be a Diamond X-50. I had totally forgotten what make or manufacturer it was. It was still in excellent condition when it was brought down from its home for the last 15 years atop an 8 foot long pole.

I investigated it and found that the PL259 had a slight amount of corrosion despite it being wrapped in self amalgamating tape and in turn being inside the lower pipe of the antenna.

Diamond V-2000 triband vertical antenna

I received the new antenna and assembled it. This one now has two set screws holding the support pipe to the base of the antenna so Diamond have listened to the criticism on internet forums about the the previous 1 set screw fixing. Now it is really strong and gives you confidence.

Yaesu FT-450D using the internal ATU at the same time as an external ATU

I have an external ATU made by LDG, The Z-100Plus Autotuner, connected to the rig with a short section of 50ohm cable (500mm long). I use this as the internal ATU inside the FT-450D will not tune my end fed dipole on any band.

Following on from a query by a local ham I need to explain I have been experimenting using the internal ATU within the Yaesu FT-450D at the same time as the external ATU and am having good results. I have the Yaesu internal ATU set to be in circuit both on transmit and receive (out of the box as a default the FT-450D is set to be in circuit just on transmit).

It must be stressed that I don't tune both ATU's at the same time.

The way I do it is tune up on the desired band and frequency using low power through the Z-100 Plus. This gets the load presented by the antenna to the rig within range. Then I press and hold the tune button on the rig and let it do its stuff too. A further tune on the Z-100 retains exactly the same settings. In other words the external ATU is still tuned so doesn't go through its tuning cycle again.

 When I take the internal ATU out of circuit while receiving a fairly stable signal I do see the S meter drop 1 or two points. I have also switched it into circuit and found that I get a noticeable improvement in reception on very weak signals.

My belief is that both ATU's compliment each other and the only thing in the manual says "Yaesu recommend keeping the ATU in circuit all the time". My view it that the internal ATU just sees a load to match to the power amplifier and doesn't know or care that there is another ATU between it and the antenna.

I am aware that there is debate whether both ATU's should be used and certain manufacturers rig operating manuals say not to do it. I only present the results that I am seeing and that is part of what amateur radio is about - experimentation. I take no responsibility for what you do in your own shack.

Avair AV-601 review

I have had an old AEC SWR-50A for the last 35 years and it has finally given up the ghost. To be quite honest it was never really good and now its adjustment potentiometer was shot. I needed another more modern VSWR/Power meter.
I opted for the Avair AV-601 as it covered frequencies from 1.8MHz up to 525MHz that covers most of the radios I have.

I ordered it from Martin Lynch on a Sunday evening and it arrived yesterday 08/07/2015 in a padded bag. I opened it and the cardboard cover for it was a little battered but the meter was inside a large padded bubble wrap sleeve and was fully protected.

Front panel

The instrument itself comprises a large metal box, solidly built and is dominated by a large multipurpose meter. There are 4 rubber feet on the bottom, it is finished in black with silk screen printed lettering. The instrument weighs 720 grams and measures 150mm wide x 50mm high x 100mm deep so should fit in a convenient location in the shack. The RF and power connections are all on the rear panel so make allowances for these connectors.

DM780 Waterfall hiccups

I noticed the other day that the waterfall was hiccuping from time to time. I thought nothing of it as "it was probably something cosmetic to do with the display driver". Oh how wrong I was.
I was in QSO with a guy on lowly PSK31 and noticed that my last 73 over to him stumbled slightly and took much longer to complete than normal.

Now my Windows 7 64 bit PC is not slow nor lacking in RAM but I investigated to find a process taking an inordinate amount of memory (almost 2GB). It was the "svchost.exe -k LocalSystemNetworkRestricted" host process. I know from my work in computers that sometimes hackers replace this file with their own.
To cure this I first of all killed the process and then ran up an administrative cmd.exe prompt (right click the cmd icon on your start menu and select run as administrator)
Then I typed in the cmd line sfc /scannow and let it run to its conclusion. This will report on whether any essential system files have been replaced with dodgy ones and repair them with the original Microsoft ones if it finds any. Fortunately it did not find any and I noticed that svchost had automatically restarted.

I monitored this over the next few days and it took no more that 220 MB of RAM - not bad for an 8GB machine.

DM780 no longer stutters. So have a look at your machine before you blame the HRD software!

For more information about sfc have a look at Microsoft Knowledgebase article here