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So I had noticed a while back, when developing my Icom (CI-V or band Data) to Yaesu BCD Band Data Converter that occasionally I could get 70MHz to show up as the band.

I always had it in mind to investigate this further.  Today I set about finding the BCD which selected 4m (70MHz) and found it with all BCD lines high (Band A=1, Band B=1, Band C=1, Band D=1, ) great!  On page 5 of the manual it shows the pin-outs, on BAND-DATA 1 or BAND-DATA 2 connect pins 4, 5, 6 & 7 together and then to 12v via a 1k resistor to get 70MHz. I noticed the amp would only allow LOW which I presume is to stop the PA’s overdriving into a non-optimized filter.  The fact that LOW is only fixed when on the 70MHz band lends me to believe the designers know this and allow it. Now to the interesting part.

With 25w in I get about 240w output, rather useful as the UK limit is 160w. Id was about 25amps though which at 33v is about 825w and means it’s about 30% efficient but none the less the amp does it.

However with 65w in I was getting a peak of 500w. 35% efficient.

I’ve not run this long term so it’s all at your own risk! I did run it for about 10 minutes to keep the dummy load cool, but for UK legal this should be a good option to get you to 160w with about 20w drive.

Update 2/1/12: G6UW ran their Quadra for 2.5 hours in the first 4m RSGB UKAC contest of the year without issue. On air their signal was clean and caused us no issue, they were an S9+50 signal with us being less than 10km away.

Just thought I would share some projects I have bits for, and can recall at the moment, but are in the waiting pile:

- APRS beacon built around a PICAXE-08M which periodically wakes up, beacons and shuts down.

- 3 x Azimuth rotator controllers. 2 for the CUWS (G6UW) and one for John G4BAO.

- Write up an AZ and EL rotator interface, basically my own version of an LVB tracker or ST-2.

- 30m QRSS CW beacon.

- RTTY modulator for my IC-756pro3 using a PICAXE-08X2 and XR2211, it already does inbuilt RX.

- Repair a mates FT-8800r.

So after sending a quick picture to Twitter showing my clean shack I got quite a few replies.  I thought therefore it would be good to show the shack in its entirety.

I first Googled to see if Picasa could do it and got a result back for Microsoft’s Image Composite Editor (could this be a #fail for Google?).  Anyhow after a straigh forward email, had to install Microsoft Visual C++ 2010 Redistributable Package and Microsoft .NET Framework 4 Client Profile, which the installer gave links for as you went I loaded Image Composite Editor, dragged my images in I had taken of the shack and it just did it, amazing!  I was able to crop out the edges and save the panorama in about 1 minute…

Lick on the image below to open it in Flickr and get more size options…

So I got the bug, got up this morning and strapped my Casio Exilim EX-G1 camera to the 6m beam, set it to interval shoot (take a photo every 10 seconds) pumped the mast up and rotated the mast slowly to get a panorama of my takeoff

So I can’t get it out of my head all the grief I got after operating within the top 3 KHz of the DX window on the 6m band…  The conditions were such that there was a chance of some North African stations being on the band so I thought I’d position myself at the top end, not the middle of the DX band incase, also I should point out in region 1 the band plans are only guidance.  People trying to tell me I can’t work EU stations are just unreal, when questioned about it NONE of them could answer my question of what needs to happen before, in their minds, operating in the DX part of the band is allowed.  Is it when they want to do it?  Do I need to keep an eye on page 5 of the Guardian newspaper? Wait till the current RSGB president announces it on a specific DX cluster?  I mean what a load of crap. 

I then asked those making the comments if they had worked any DX on the band which I was causing interference to.  If I was then what?  QSY out the DX band to give them the frequency?  Rubbish! If DX is being heard then I would also be DX to the other location thus justifying being in the DX portion of the band to begin with! I have 400w and a 5 element on 6m so I would easily be heard before most…

Lots of their argument stem from me working stations in EU so in their mind I should become ignorant and ignore any EU stations calling me, they didn’t even suggest I should call “CQ outside Europe” or similar which makes it even more obvious to me they don’t have a clue and are just moaning to satisfy themselves – they can’t even advise people like me on how to ‘appropriately behave’ in the DX band when complaining and this really annoys me, if you are going to complain about something at least be ready to suggest the reasons behind your complaint and suggest an alternative/solution.

So in summary calling in the DX window might yield the first DX of the day, if there is DX, as advised in page 5 of the Guardian newspaper, then I can safely operate in the DX window but what needs to come first, the CQ or DX?  Also once DX was announced wouldn’t everyone else cram themselves into the 30KHz DX windows of 6m instead of the other 70KHz, and after what time should everyone QSY out of the DX window? 1 hour after the RSGB president goes to bed on the day when there was DX stations on the band? Do we wait to work DX outside the DX window before these people say we can use the DX window? If DX is being worked outside the DX windows then what is the point of the DX window in the first place??? Please someone tell me!!!

It has been a busy month.  First I was on holiday for 2 weeks, one week at my parents in Scotland and the 2nd I was on the Isle of Arran for the Camb-Hams 2011 DX’Pedition.  The DX’Pedition was sponsorship by Kenwood UK, Icom UK and Linear Amp UK.  The latter provided us with an HF amp (Challenger) and a 6m/4m (Discovery 64) amp.

On the DX’Pedition we planned to make about 4000 QSOs in the week, this is about what we have managed to do in previous weeks on our DX’Peditions.  So when we managed 4000 after 4 days we thought maybe we will manage 6000, in the end we managed 9100 QSOs!!!  At times we were on 6 bands running simultaneously and most of the time no less than 3.  We also managed to get out on the 2m RSGB UKAC where we managed 49 QSOs and 16 squares.  The only thing which broke was the motor driving the elevation rotator as the controller has a mind of it’s own, somehow faulty, and now and then enables (and sticks on) one direction, in this case UP and we only noticed after 15 minutes of the motor trying to drive the rotator after it had hit the mechanical end-stop.  This is now fixed as I had a spare motor at home.

It was the second year we have borrowed the Discovery 64 and since last year I have been thinking about a 6m amp for the shack.  I didn’t want to get an amp which only covered 6m though, mainly for space, and I wasn’t compelled to buy an HF amp either so I didn’t bother buying anything.  This year however with having 3 HF amps on the DX’Pedition I was sold on getting an HF amp, even conservatively running them at 300w, a 4.8dB increase on the 100w the radio produces, yielded a much higher QSO rate and allowed us to keep our frequency on a crowded band.

So now I was sold on the virtues of an amplifier for 6m and HF I needed to find one which done both.  As luck would have it Martin Lynch and Sons, a large UK ham radio supplier, had just added a Yaesu VL-1000 Quadra to their second hand section a few days before I decided I wanted it.

The Quadra is a solid state 1KW on HF and 500w on 6m amp which requires minimal startup time, instant [no tuning required] band changing, 4 antenna connections, 2 radio inputs and a built in ATU.  The only slight issue [for me] is it uses Yaesu’s band data (4 pins) for band selecting and I will use an Icom IC-756pro3 to drive it, which doesn’t have these data pins.  Solution: buy the amp, which I did on the spot, then make a PICAXE interface which translates Icom data to Yaesu data which was done a week later…

I had to do a bit of shelve re-arrangement in the shack to fit the Quadra in so thankfully my shelving is plug and play.  One thing I found out quite quickly, it was something I had read about was the noise floor increases on 6m.  It turn out the display board and the control board, which sits just behind the top right of the display produces lots of RFI on 6m. Some intensive screening using EMC tape fixed the issue!  I’ll write more about this later…

So about a week ago I tweeted that my PC had crashed and on boot-up I got error messages saying there were missing DLL and SYS files for the programs which were running when the crash happened.  All week the PC had sputtered which was uncharacteristic of it being quite a decent machine.  I decided to run the Maxtor disk check utility which it failed the disk and recommended I replace it, so after a reboot to do more detailed test it failed to boot, missing a ntoskrnl.exe file!  So I left it hanging on that screen for a bit then noticed the PC had switched off, I assumed it was cause it was doing nothing – WRONG!  The PSU was dead now, so that was a duff hard drive and PSU.  Thankfully I had a spare PSU but I had to go out and get a new HD.  Got that and fitted it with the new PSU but had to wait 4 hours for the Windows XP hard drive test utility to finish incase it could cure my issue so I could image the drive.  Once that was done I wired it all up and switched it on and this is when the real fun started as you can see in the video:

So off again to the PC shop to get a new graphics card which is now fitted and cause my original HD is dead the new one has just been installed with a clean install of Windows XP, not quite brave enough to see if everything I use will run on Windows 7 yet.

So I’ve been after a few RF switches to allow me to switch various radios to various antennas. In this instance I wanted to switch antennas to my IC-910 radio (the 2m and 70cm side only), my funcube dongle and 2m transverter (connected to my Flex-1500).  The antennas were my 2m 9 element YU7EF, the 7 element and 70cm 10 element cross yagis.

So in sequence from the bottom right switch, C = common port, R = right port and L = left port (as seen in the photo:

Bottom right = C (9 element yagi) to R (2m tranverter) and L (IC-910 switch). Middle bottom = C (2m 7 element cross yagi) to R (IC-910 2m switch) and L (funcube dongle switch). Left bottom = C (70cm 10 element cross yagi) to R (funcube dongle switch) and L ((IC-910 70cm). Top right = C (2m port of IC-910). Top left = C (funcube dongle)