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Yesterday I made a secong attempt to activate Scafell Pike. Usually I got up to summits alone or with the dog bit this time was with a bunch who were training for the 3 peak challenge. Needless to say the summit was in cloud, it snowed then hailed then rained on me as I came down. Still this time I had a whole load more qso’s and a much more satisfying activation. Wast water (in the photo) is a beautiful lake that is surrounded by some impressive fells. Not as nice a Ennerdale but then again I am a bit biased.

I managed to sneak into the lab again at lunch today for a few minutes and hooked up the now-packaged W1GHZ 903-MHz transverter to do a transmit gain compression test.  This test is a quick and dirty way to find the linear operating region of the transverter in addition to the expected conversion gain on transmit.  These two parameters determine the IF transmit level and what kind of power amplifier or driver stage will follow.  It’s an easy test to run if you have the equipment.  I locked the transverter in transmit by applying 8 volts to the TX MMICs and used a Rodhe and Schwarz SMR40 signal generator as the IF transmitter at 147.100 MHz.  On the transverter TX output, I simply connected the HP 8565E spectrum analyzer that I’ve used in the past.  Spectrum analyzers are not great power meters, but they give you a good enough idea of what’s going on.  The 1-dB gain compression point (that is, the point where the actual device gain sags 1 dB from the linear gain) is at an input of -3 dBm or an output of just under 10 dBm.  This compares favorably with the datasheet for the mixer and discussion with N3UM.

For reasons that will become clear in a future post or series of posts, we’ve been busy lately—don’t worry, it’s a good thing.  I did manage to sneak away from my regular (usually desk-bound analysis) work into the lab and tune-up an eBay-special cavity filter for 903 MHz with our new network analyzer.  It’s really amazing how you can dial these things in if you have the right tools.  This one is a 3-cavity filter about 10x8x3 cm.

Passband insertion loss is about 1.2 dB.  Harmonic rejection at 1.8 GHz is 70 dB down.  I’ll take it.

I also have some eBay-special helical filters that were advertised to be for 432 MHz.  So, I need to cobble up some carrier boards to try them out.  Another day, another project.

For those who are following the progress of the ultra cheap pc proposed by Raspeberry Pi, I received this email this morning.

The Raspberry Pi Foundation will be making a big (and very positive) announcement that just might interest you at 0600h GMT on Wednesday 29 February 2012. Come to www.raspberrypi.org to find out what’s going on.

Eben Upton
Executive Director, Raspberry Pi Foundation

Perhaps they’ll be announcing pricing and delivery of what should be very useful lightweight PC’s (is that even the right way to describe them?)

The amount of 6 and 10 reports that I was hosting was begining to cause me a headache with space so I’ve shifted them onto a Dropbox public folder which can be accessed here. There is limited demand for these older reports but I hope they are useful to someone. Let me know if there are any problems.

I’ve long been a user of smartphone’s and always felt that in the past they were able to offer a lot in terms of being able to make and receive calls then the applications or apps that run on them we additional bonuses. Nowadays the primary selling point of a smartphone is not to do the basics like calls and text (SMS) messaging are the apps. My HTC desire S is like many other that run the Android OS in that it has access to the Android Market and its ever growing list of extras. A little run down on the ham radio one I have is as below. There’s no great explanation as to their functionality as its all on the Android Marketplace

APRSdroid – APRS on your phone. Well worth the money especially now that it supports messaging.

Echolink – Ro real need to introduce this application. Just does what you need to make use of the Echolink network

Electrodroid – A collection of electrical references

Hamsatdroid – Satellite prediction for your phone. Very effective with a simple interface.

Morse code reader – Like all readers its not as good as your ear and as such is limited but a simple application

Morse CT – The trainer that if it was a person would have given up on me learning the code a long time ago. A very patient trainer.

Repeater – Repeaters in you local area. Shows you the distance to your nearest repeater.

Satellite AR – A mixture of Google sky maps and hamsatdroid with a nice ‘point at the sky and see where the satellite is in real time’ interface. Does more than amateur radio satellites.

This is by no means an exhaustive list but these are the ones that have been installed and used. I’ve tinkered with the idea of a log book for when I’m portable but nothing so far has stood up to the old pencil and paper. If a developer makes one that can pick out call signs then that would be smart but I can imagine that’s not going to happen in the near future.

I know there are apps for digimodes like PSK-31 but nothing for things like WSPR or any of the exotic ones. As the next generation of phones come out and these become functional but obsolete the ability to repurpose them must be on someone else’s mind and not just mine.

Well I can call it a summit because it features in Wainwright’s book but it really something to write home about as far as height for me. But, there’s always a but, I decided to go with the XYL, kids, mother in law (not sure what the shorthand is for one of those) and two dogs. Abigail is my eldest at 5 years old and Sam is only 3 so to them this was a veritable Himalaya.

Progress as you can image was at their pace and eventually I had an extra 20Kg on my shoulders as we went back into the cloud near the summit of Dodd (LDW-174). The summit is low at only 502m but the propagation into both Southern Scotland and Northern Ireland was in effect and I managed a summit to summit before the kids / XYL got bored. Needless to say the dogs didn’t bat an eyelid.

So I’m off the mark for this year and hopefully I’ll be able to get a few SOTA and WOTA summits in this year although I think I’ll avoid carrying the kids. The lake district is an excellent place to live and visit and I’m glad to have made some new contacts for the log and I hope it will help WOTA to grow and grow