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Saturday, 11 August 2018

60m or 5MHz and all that Jazz


Lat time you may recall that I mentioned I had constructed two new wire antennas; one for 40/30M and one for 80/60M.

60M or 5MHz is a new (ish) allocation in the UK and I had to think carefully how to make sure I stick to the frequency allocation. We have a bunch of 'bandlets' and we are not allowed to transmit outside these frequencies.

So, looking at my newfangled IC-7610, I can see that is has a feature whereby you can configure user band edges and also set up the radio so the TX is inhibited outside these ranges.

To turn on this feature, we enable "Band Edge Beep" to be "On (USER) & TX Limit" as below:

Once that feature is switched on, you can then select an option "User Band Edge" and enter new band edges for the radio to use:

So in the images above you will see that the item numbers 4 to 13 are the UK allocations (note I have subtracted the SSB bandwidth from the upper frequencies in the SSB segments).

So now, as you tune through the band, the TX is enabled in the bits we are OK to TX and disabled where we aren't:

So above you can see the line round the TX is solid at 5.262 MHz meaning the radio will TX, but at 5.258 (which is below the bandlet) it's a dotted surround meaning TX is disabled.

I've stuck my radio config file here if you want to download it. In the latest firmware you can even just import the band edge settings without bringing in all my other config if needed.

Most excellent - well thought out Icom.

Monday, 30 July 2018

Trap Dipoles - Really?


I've been fiddling with my wire antennas - never quite being satisfied with what I had.

Prior to this change I had a 30M dipole plus a full size Windom.

I saw some traps advertised by Spectrum Communications and the idea of a combined 30/40M antenna and a separate combined 60/80M antenna appealed.

The traps themselves are really very small and lightweight:

I bought traps for 10.125 MHz and 5.35 MHz.

The 30/40M antenna uses 24ft from the feedpoint to the trap and then 5' 8" as a tail on each end.

The 60/80M antenna uses 44ft from the feedpoint to the trap and then 11'2" to the end.

I've used "flexweave" cable I had here already.

I've also used some balanced feeder for the first time - also from Spectrum - it's very thin and needs a balun at the Shack end but the noise reduction on the low bands is very noticeable.

It always takes time to evaluate new antennas, but so far I'm more than impressed.

Good. don't you think?

Saturday, 14 July 2018

Some Casual Contesting


This weekend is the IARU HF World Championship and I have been having a dabble in CW.

I have three monitors connected to the "radio" PC, the primary screen has my main Logger32 window:

Going clockwise you can see:
  1. Great circle map plus beam heading - any DX station entered into the log entry window is also placed on this map;
  2. The pink/purple bar lists the station I am workings callsign and country;
  3. Below the pink box you can see a list of previous QSOs with the callsign being worked plus the incoming DX spots;
  4. The next window is "worked/confirmed" this lists the country/prefix being worked and shows the status of each slot i.e. not worked, worked, confirmed;
  5. The top right window is the telnet connection to my DX Cluster of choice;
  6. Below the map on the far left is my logbook window, the colour of the entry tells me if it is yet to be uploaded to LOTW and if the QSO is confirmed;
  7. To the right of the logbook is the QSO entry window including frequency and mode read from the radio directly. There's also a lookup to to auto populate name grid et cetea.
  8. Then we have 10 bandmaps which list the recent DX spots by band and frequency - clicking on a spot tunes the radio.
The left hand screen is watching out for any opening on 4M using dxmaps:

The third monitor has a number of other applications, firstly, we have CW skimmer to help me with CW RX at high speed - here we have YT0HQ at 37 wpm:

Then I have my CW Machine - this is part of the Logger32 application and is a CW keyboard with macros - simgle click on the maco or any text typed in is sent as CW:

And finally we have the remote software for the SPE Amplifier we discussed back here:

The amp is performing flawlessly since its return from the manufacturer. It has a lot of ATU frequency memories and as you tune between parts of the same band there is no need to worry at all about the antenna match - its just a case of setting it up once with your antennas and then forgetting.

The Antenna selection is also automatic as you switch bands on the radio - there are CAT interfaces from both my Kenwood TS-990 and Icom IC-7610. So the preference from 4 antenna sockets is auto selected by band.

With auto band, antenna and ATU settings its foolproof and is performing perfectly - I'm delighted.

Here's our Elmo looking like he has the worlds problems to worry about:

Good, isn't it?

Monday, 18 June 2018

Splashing Complete


Following my recent post back here about my bonkers SPE 1.3K-FA Amplifier, I thought I should post an update now it's back from its short vacation in Italy.

It has been back to the factory for three issues:

  • Front Panel missalignment
  • Very noisy fans
  • Attenuator fittment

So, I am please to report all three issues are sorted on the amplifier and the drive levels, whilst still somewhat bonkers, are very much more reasonable and within the range that I can actually control from the radio.

Luckily, my main radio (The TS-990) is extremely well thought out, and within the menu system you can set the granularity of the power out adjustment:

So  I can now set the output level exactly as I require on each band.

Here's a quick video of the amplifier now its back:

You can see the automatic band switching working - I have this working on both the Kenwood and my IC-7610 radios - you can also see that 5W drive now gives me 250W and 8W gives me full UK legal limit.

I haven't yet played with the in-line attenuator I made back here, but will do soon.

I've actually used the output from my MicroHam DigiKeyers to drive the CAT control from the rigs, so I can also keep the CAT line into the computer for logging and other control purposes.

All good.

Sunday, 17 June 2018

It's a Kind of Magic.....


6M AKA "The Magic Band" sometimes simply amazes me.

Today I have worked Cuba, Puerto Rico, Dominican Republic and Haiti.

Here's my all time 6M QSO log as a map:

Amazing, isn't it?

Sunday, 10 June 2018

TS-990 on 144MHz


Following some discussions at Ham Radio 2018, Friedrichshafen, I've done another example video of the TS-990 with a G4DDK transverter:

There's a document I've compiled on the transverter setup here.

Here's one of the halls full of goodies that I don't need from the rally - it really was very good:

and some of the test gear on offer:

And here is my very lovely Luna cat enjoying a snooze in the shack:

and finally, Miss Florrie Cat:

Good, egh?

Thursday, 7 June 2018

Taming the Amplifer


Following my recent purchase of an SPE Expert Amplifier I described here, I've been pondering how to keep the amplifier under control. It is currently back at the manufacturer for three issues:
  1. Extremely noisy fans;
  2. Bent front panel;
  3. Attenuation fitting.
I attended Ham Radio 2018 at Friedrichshafen this year and spoke to the owner (Dr. Gianfranco Scasciafratti I0ZY) of SPE while I was there. I tried to explain my concerns about such low drive level requirements and the reliance on ALC and associated risk of failure; the conversation concerned me because he didn't seem to want to listen to a word I said.

SPE have sent a video of my amp under test:

So hopefully it's on its way back to me now.

I've designed a thingamabob to put in-line with the amplifier as recommended by I0ZY to provide attenuation to the input drive level. Gianfranco suggested that the attenuation could be permanently in-line as on receive it "didn't matter". However, I'm not happy with that so I have come up with the following to switch the attenuation in line during TX and remove it during RX:

In reality the build looks like this:

There are quite a few bits in there, there are two coax relays (50 GBP), the connectors and the resistors in the Pi Attenuator (50 GBP) plus the case and other assorted bits and bobs (75 GBP) - so a total of 175 GBP just to tame the amplifier. Of course, I will need two of these if I want to use the amp as designed with two radios. I find it odd that they would recommend such a solution - why not just put sufficient attenuation in the amp to start with?

The gubbins has a good flat response from 0 to 50Mhz and also give us about 6.16dB of attenuation.

Throughout the build construction Florrie Cat has been assisting:

and somehow, you just know it's not going to end well:

Odd situation, don't you think?