Some Casual Contesting

Well,

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 QRZ.com 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?

Splashing Complete

Well,

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.

Taming the Amplifer

Well,

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?

Splashing Out Somewhat

Well,

I decided to get myself a new toy. The idea is that this replaces the linear amp, the antenna switching, the radio switching on HF plus the ATU - all in one box. Also it doesn't need to "warm up" or tuning on each band.

So I brought it home, somewhat excited:

Now, I first tried it with my TS-990 as the exciter. The manual doesn't actually tell me anything about required drive levels, but anything from the TS-990 generates "INPUT OVERLOAD" error - even only with 5W output. So more consultation of the manual and it seems they are keen on you using ALC connections to control the exciter drive levels, so I hook up the ALC line and then this is what happens:

Now that's really quite strange.

Next I try the IC-7610, connect up the ALC and PTT lines and it seems to work OK, however, I have very little control over the RF out - in fact I cant get the amplifier to deliver less than just over 500W output even on the lowest power output setting. That's not very clever - I want to be able to control the RF and gain of the amplifier.

So, some email back and forth to the manufacturer and it seems there are two versions of this amp. One for the US market which includes an attenuator in the drive line so that 25-30W of RF is required for full output, and an EU version without the attenuator.

SPE sent me this table which shows the input RF needed for full output by band and power setting (you can have the amp on Low, Med, High):

So at this point I fell off my chair! This amp eneds only 2W of drive on the low bands for maximum output. The only way that low level of drive is possible with most modern transcievers is by using the ALC all the time to restrict the output of the rig - which is exactly how this amp is "designed" to operate. I think the issue with the TS-990 is that despite ramping the ALC voltage to the most -ve it can, the output is still too high to drive the linear.

Either way, there is no way you can set the controls to deliver, say, 200W output. You can have maximum bananas (which seems to be 500W, 1Kw and 1.3Kw) depending on the Low, Med or High selection of the amp power switch.

The manufacturer recommends you run your rig at FULL RF output and rely 100% on the ALC circuitry to protect the MOSFET in the linear from being fried. I personally don't like this theory at all.

Needless to say the amplifier has been returned today for modification to the USA version so I have some hope of controlling the RF output.

Here you see the drive level of 3W:

which produces 508W out in the "low" power setting:

Bonkers, don't you think?