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The F-117 Nighthawk, designed by the Lockheed ‘Skunkworks’. (Image in public domain from Wikimedia Commons)

I have just finished reading ‘Skunkworks’ by Ben Rich and Leo Janos and it should be one of those books that engineers, students of engineering and those that like technology should read. The book details the secret Lockheed Martin aircraft design branch, set up and run by Kelly Johnson, which became known as the ‘Skunkworks’. Out of this special projects group came the F-104 Starfighter, the U-2 spy plane, the SR-71 Blackbird and the F-117 Nighthawk (also called the stealth fighter), amongst other aircraft.  The book starts out with the development of the Nighthawk which was developed by a team led by Ben Rich, who replaced Kelly Johnson as the head of the Skunkworks.  After telling that story of the stealth fighter development over the first few chapters it goes back in time to when Ben Rich first joined the special projects unit and how he became involved in the development of some of the most advanced military aircraft of the 20th Century. The book is an exciting insight in to how advanced engineering projects can be run.  ’Skunkworks’ was allowed to be free from the usual corporate bureaucracy and therefore it could move quickly in development. There was also a philosophy of using off-the-shelf parts as much as possible, including engines, so reducing delays from manufacturing new parts that would then need to be continued to be produced.  Although this philosophy was challenged with the development of the Blackbird which was designed to achieve Mach 3 speeds and so needed to be constructed with large amounts of titanium.

Combining details of how the planes were developed, the challenges and uses of the planes, as well as some insight into management styles and how to obtain multimillion dollar contracts make the book extremely interesting. When you read about the uses of the U-2 in the Cuban Missile Crisis, the shooting down of Gary Powers, and the use of the F-117 in Iraq you can see these aircraft had influencial and important roles in the the Cold War period and beyond. It was also interesting to read about the irony of how a relatively obscure Russian paper on electromagnetic theory  lead a young mathematician at the Skunkworks to propose how they could devise an aircraft that was almost invisible to radar.

Check out your library or bookstore to find a copy of ‘Skunkworks’ and read about engineering at its best.  To illustrate the performance of the U-2 here is a video from the BBC where presenter James May gets a flight in the two seater version of the U-2.  You can see how the U-2 could fly so high it was out of range of fighter jets and missiles (although there is a report of an English Electric Lightning F3 intercepting one at 88,000ft during a NATO excercise in 1984).

Onto the second engineering biography book to read.  This is ‘iWoz’ by Steve Wozniak and Gina Smith, which I read a year or two ago and should have written about sooner.  This is the story of Steve Wozniak, co-founder of Apple and the real technical brains behind the development of the first Apple computers, including the massively successful Apple II.  This is a very personal account, and more like a traditional autobiography than ‘Skunkworks’, but there are some interesting insight into how ‘the Woz’ come come up with the design for computers that effectively started the microcomputer revolution. It is fascinating to read how in high school he collected minicomputer manuals and with the help of catalogues and datasheets of newer components he would redesign the circuitry of those computers to use fewer components. Also interesting is his interest in using components in more than one way on the same board.  Here you can see the real engineering genius coming through. Below is a short clip of Wozniak talking about the ‘economy’ of the design of the Apple II at book signing event for ‘iWoz’.

Summer is not far away so chase down one or both of these books for your Summer vacation.  Lots of engineering inspiration is contained within the both books.

I think I mentioned a few weeks ago that OFCOM had offered us the chance to use a special prefix to celebrate the wedding of Prince William and Kate Middleton (have you noticed how she’s become Catherine recently!). The special call can be used from the date of their wedding, 29th April for 11 days.On the day of the wedding my QSOs were all on 70MHz – but it was nice to catch up with some of the locals as I was using the special call. I was out and about a little from the mobile on both 144MHz and 433MHz too, so fun to use the call there too. Tried a few CQs on 29.600MHz FM, but no luck!Today, I caught a little sporadic E on 50MHz this morning, so worked I0JX and I0WTD from the Rome area. Once again, tried a CQ on 70.200MHz but no luck. Also had a really nice DSTAR QSO with Gordon, G8PNN from Northumberland who I’d not spoken to for years. It was really good to catch up and hear about some of the interesting QSOs that he’s been having recently – including optical ones!This afternoon, after some pleasant 70MHz FM QSOs, I biked over to Windmill Hill taking the FT817 and whip as well as the Icom IC-E92. 28MHz was quite interesting and I was pleased to hear some African DX coming through; ZS1AX, ZS1ACH and a 5R7 (I think) all on phone. Heard a I3 working into Brazil (PP5) on CW and A61Q on 24MHz CW before switching over to VHF/UHF.I called through GB3UK on Cleeve Hill and worked Mike, G4UXC a friend from a long way back. We were licenced around the same sort of time and it was good to work him with the special call. Last but not least, before pedalling back to Longworth was a QSO with John, G4SRE/M in Swindon. John’s a great 70MHz FM enthusiast so we swapped news about the band. John’s a native of South Wales and I’m hoping that I’ll be able to work him on 70MHz FM from a mountain top in Wales at some point! Ought to be able to do it from here…And this evening, I was pleased to work the Camb-Hams expedition to the Isle of Arran, GS3PYE/P on 7MHz – probably my first 7MHz SSB QSO in a couple of years!

I think I mentioned a few weeks ago that OFCOM had offered us the chance to use a special prefix to celebrate the wedding of Prince William and Kate Middleton (have you noticed how she’s become Catherine recently!). The special call can be used from the date of their wedding, 29th April for 11 days.On the day of the wedding my QSOs were all on 70MHz – but it was nice to catch up with some of the locals as I was using the special call. I was out and about a little from the mobile on both 144MHz and 433MHz too, so fun to use the call there too. Tried a few CQs on 29.600MHz FM, but no luck!Today, I caught a little sporadic E on 50MHz this morning, so worked I0JX and I0WTD from the Rome area. Once again, tried a CQ on 70.200MHz but no luck. Also had a really nice DSTAR QSO with Gordon, G8PNN from Northumberland who I’d not spoken to for years. It was really good to catch up and hear about some of the interesting QSOs that he’s been having recently – including optical ones!This afternoon, after some pleasant 70MHz FM QSOs, I biked over to Windmill Hill taking the FT817 and whip as well as the Icom IC-E92. 28MHz was quite interesting and I was pleased to hear some African DX coming through; ZS1AX, ZS1ACH and a 5R7 (I think) all on phone. Heard a I3 working into Brazil (PP5) on CW and A61Q on 24MHz CW before switching over to VHF/UHF.I called through GB3UK on Cleeve Hill and worked Mike, G4UXC a friend from a long way back. We were licenced around the same sort of time and it was good to work him with the special call. Last but not least, before pedalling back to Longworth was a QSO with John, G4SRE/M in Swindon. John’s a great 70MHz FM enthusiast so we swapped news about the band. John’s a native of South Wales and I’m hoping that I’ll be able to work him on 70MHz FM from a mountain top in Wales at some point! Ought to be able to do it from here…And this evening, I was pleased to work the Camb-Hams expedition to the Isle of Arran, GS3PYE/P on 7MHz – probably my first 7MHz SSB QSO in a couple of years!

The 6 metre band is showing signs of life, as this map of WSPR activity from this afternoon shows.

However, some of the traces on the WSPR application screen look a bit odd.

I don’t claim to be an expert but I think what I am seeing is the result of doppler shift on the signals being reflected by fast-moving Sporadic-E clouds. In several cases what seems to be a trace has not been decoded.

I’ve said this before, but I wonder if WSPR mode with its 110 second transmit periods and tiny frequency shift encoding is really suitable for detecting Sporadic-E propagation. But no-one has ever commented on this, leaving me to wonder whether they think I’m an idiot who doesn’t know what he is talking about or whether nobody knows.

The digital mode most people seem to use on 6m is JT6M, however this entails using the WSJT program which I find rather confusing. I’m interested in trying JT65A but I’m not sure if it is any more suitable than WSPR for this type of work.

In the absence of any expert advice I’m going to try JT65A using a dial frequency of 50.276MHz. With the JT-Alert accessory to tell me when anyone replies I can leave the rig calling CQ whilst I am otherwise occupied. It will be interesting to see what we can work on 6m with the JT65A mode.

The 6 metre band is showing signs of life, as this map of WSPR activity from this afternoon shows.

However, some of the traces on the WSPR application screen look a bit odd.

I don’t claim to be an expert but I think what I am seeing is the result of doppler shift on the signals being reflected by fast-moving Sporadic-E clouds. In several cases what seems to be a trace has not been decoded.

I’ve said this before, but I wonder if WSPR mode with its 110 second transmit periods and tiny frequency shift encoding is really suitable for detecting Sporadic-E propagation. But no-one has ever commented on this, leaving me to wonder whether they think I’m an idiot who doesn’t know what he is talking about or whether nobody knows.

The digital mode most people seem to use on 6m is JT6M, however this entails using the WSJT program which I find rather confusing. I’m interested in trying JT65A but I’m not sure if it is any more suitable than WSPR for this type of work.

In the absence of any expert advice I’m going to try JT65A using a dial frequency of 50.276MHz. With the JT-Alert accessory to tell me when anyone replies I can leave the rig calling CQ whilst I am otherwise occupied. It will be interesting to see what we can work on 6m with the JT65A mode.

Sometimes conditions on the fell-tops are not what you expect when you leave home. Yesterday, having no desire to watch the big event in London, I decided to have a big event of my own, namely to activate two of the Northern Fells for Wainwrights On The Air (WOTA). Although the weather was a little hazy there had been several sunny days and I anticipated two leisurely activations lazing in the grass and basking in the sun beside my guyed WOTA Pole, perhaps even some DX due to atmospheric conditions. I did notice a chilly breeze as I went out to the car, so I went back and got an extra fleece. That turned out to be a good move.

It was about 45 minutes drive to the parking spot at Caldbeck Common. I set off on a circuitous but easy climb up to High Pike, the first summit, working Jimmy on Blencathra who was using a special Wedding call MR3EYP/P on the way. No getting away completely from thoughts of the big event in London.

Half way up I noticed the wind was getting stronger and chillier. The extra fleece was quickly donned, and I worked another activator with a Royal call, MR1EYO/P on Red Screes. By the time I reached the summit I felt conditions were such that I didn’t want to stay long up there. After a contact with Bill G4WSB/P on Grasmoor whose voice was at times unintelligible due to wind getting into the mic of his Quansheng, I walked down from the summit in search of a slightly less windy spot to eat my packed lunch.

Whilst eating my lunch I weakly heard Derek 2E0MIX/P on Maiden Moor but I didn’t dare nip up to the top to make a contact in case my rucksack and other things blew away. When I did return to the summit I found the wind was blowing icy rain into my face. I didn’t have any enthusiasm for putting the WOTA Pole up as I didn’t intend staying there long enough for the effort to be worthwhile. I also didn’t want to get the non-waterproof Kenwood TH-D72 – which I’d taken after realizing the limitations of the receiver of the VX-8R – wet. So I sat on the stone bench near the wind break on the summit and using the 8in. helical rubber duck rapidly worked 7 of the ‘usual suspects’, contest-style, then stuffed the Kenwood in the rucksack and set off on my way to the next summit.

Carrock Fell is is a rocky summit with a big cairn, overlooking a valley. By the time I got there the rain had stopped and the wind had dropped a bit and seemed less cold. There were numerous large rocks scattered about making inviting seats. I decided to put up the WOTA Pole. First, I had a fight untangling the guys, which had knotted themselves together. Then, while pulling up the antenna using the third guy, doing my trick of using my walking stick as a bottom section for extra height, there was a crack and the antenna fell back on the ground. The jointing piece between the lower two sections of plastic tube had cracked. Arrgh!

So I was forced once again to do the activation using the 8in. helical rubber duck. However one piece of equipment favourably surprised me. Well, two, really. I began to get used to the Kenwood TH-D72 and felt that perhaps it is a viable alternative to the VX-8GR to use on activations. I received several APRS messages while I was up in the hills and found it easy to read and reply to them. Before I set off I used ?APRSO to load APRS objects for the two summits into the radio which I used to help navigation and check proximity. Very useful, though having to page forward a couple of times is less convenient than the VX-8’s all in one view.

I’m still not convinced that the Kenwood’s snazzy metallic grey paint and plasticky casing isn’t going to start showing marks from the rough and tumble of use up in the mountains. And the radio does sometimes do things I don’t understand, like beep and do nothing when I press the PTT, or beep and mute the audio of the station I’m listening to until I press the PTT again. I think this may be something to do with the APRS functions but it confuses me. The battery endurance doesn’t seem to be as good as the Yaesu either. But I’m learning to love it.

This was also the first time I could try out a headset for the Kenwood that I’d bought for £3.99 on eBay. The price, which included shipping from Hong Kong, was so low I doubted that it could be any good. But it was also cheap enough to be worth a gamble. It turned out to be the ideal accessory for operating from windy hilltops. The microphone has a foam muffler and even with my head turned so that wind was blowing on to the mic stations reported that there was only very slight wind noise, not enough to interfere with copy. With my head turned away there was no wind noise at all. Experienced activators will know just how hard it is, when it is windy, to find a position that keeps the wind out of the mic on the front of the radio.

Despite the unexpectedly nasty weather I had a nice walk and two successful activations. I may have one last try with the WOTA Pole. I will superglue the cracked jointing piece and then try reinforcing them with nylon cable ties. If that doesn’t help then I must give up the idea or accept that it will only work with longer tubes and only one joining section.