Back in the 1960s, when in its heyday, I was a keen member of the International Shortwave League (ISWL). In those days its membership was measured in thousands from all over the world.
A few years ago I rejoined and enjoyed the monthly magazine called Monitor. I contributed a few articles too. Sadly, membership has been declining steadily and now, I believe, the membership numbers fewer than 300 people. The club keeps going as a result of the dedicated hard work by its voluntary staff who put together the magazine each month.
This last year I have started to take the magazine as a .pdf copy. It really isn't the same as a paper magazine you can take to bed and flick through. I find the pdf version much less satisfying.
After some thought, I've decided not to renew my subs this time as it is surely now only a matter of time before the ISWL folds. It served its purpose in its day, but those days have passed. This last month a final coffin nail was the closure of the ISWL QSL bureau, one of the last to process broadcast QSLs as well as amateur ones.
6 May 2013
4 May 2013
The £20 DECENT HF transceiver challenge
Ideas for the £20 (or less) new HF transceiver so far, based on past experiences:
GQRP club sales offer some very good prices for components if you are a GQRP Club member. If you are not a member then you are missing out on the very best magazine (SPRAT) available. I cannot recommend SPRAT and the GQRP club highly enough.
- VXO controlled, single band- GQRP crystals are inexpensive, but will allow around 10-15kHz easy pulling on 14MHz, more on 21 or 28MHz.
- Single balanced diode RX mixer - homebrew with low cost diode and toroid matching
- 2N3904s everywhere - these low cost (5p or less), ubiquitous transistors work well as oscillators, PAs (if several paralleled up) and are OK in audio stages. Maybe an IRF510 PA if a lower HF band chosen,
- Deadbug build - on a small piece of copper laminate and low cost using a few MeSquares to help ease construction
- Low cost metal box - e.g. Maplin Aluminium box or a diecast enclosure. A mint box would be less expensive but too small.
- Few controls - a 1k pot for RF gain is all that's needed on RX
- Capable of running from a PP3 9V supply or external 12v - rechargeable 9V packs are low cost from 7dayshop. 69p each non rechargeable and £2.60 for a rechargeable one.
- Low-Z stereo headphones will be less expensive than a crystal earpiece these days - may need an extra audio stage but at around 10p for this, this is a price worth paying.
- Probably CW, although DSB not out of the question.
- No ICs at all - these are too expensive (maybe an NE602 might be cost effective and I'm not sure about a low cost IC for the RX audio).
- TX-RX offset essential - so that listening on the actual TX frequency is possible
- Does not have to be pretty - the aim is a transceiver that can be thrown in a rucksack and survive reasonable abuse levels.
- Wire antenna - a simple dipole or end fed half wave.
- At least 2W RF out, ideally 5W - so that the rig has a reasonably good chance of being heard on a busy band
GQRP club sales offer some very good prices for components if you are a GQRP Club member. If you are not a member then you are missing out on the very best magazine (SPRAT) available. I cannot recommend SPRAT and the GQRP club highly enough.
Labels:
low cost,
qrp,
transsceiver
Back home again
In all, not that many hours of actual operation in between just relaxing and enjoying the very best part of England. I say this as this is my "promised land", where I was born and brought up. Out of season, when there are few tourists around and in weather like we had last week - perfect wall-to-wall sunshine - there is honestly no better place on this planet, but then I am biased.
My video, taken yesterday, shows the town of Salcombe in South Devon where I lived until I was 10 years old. In those far off days I took all this for granted: I knew nowhere else really. The view from my junior school window was up the beautiful estuary and the sunlight playing on the water would reflect on the classroom wall. Sunny days indeed, long before ham radio and the worries of adulthood.
Now I'm back home my challenge is that £20 (all new) portable backpack transceiver with decent performance that I've been challenged to design. In between cutting grass, weeding and paying the bills!
2 May 2013
Farmyard DXing
A carpet of bluebells on a Devon woodland walk today |
Labels:
qrp portable
1 May 2013
More seaside DXing today
Location today at Rock House beach at Thurlestone, Devon |
One thing is amazing when operating from electrically quiet spots: signals just appear out of a silent band, quite unlike the situation at home where the noise floor is always many dB higher. I had no idea how good the noise floor on my FT817 could be!
Another observation is that most DX stations would be workable 2-way (with 2W) but it is the competition in pile-ups that causes the problems most times. On WSPR, all stations have an equal chance of being copied or copying DX stations, so this gives a much better idea of real propagation with low power.
QRP DXing from clifftop and coastal sites is great fun, but it is more of a masochistic rat race in the last analysis. A few days is fun, especially in the lovely sunshine. More than that I'm not so sure. When I told my wife that I wasn't getting too many contacts as other people were using much more power and got heard first she said, "why don't you use more power then?". Hmmm.
Labels:
clifftop,
devon,
dxing,
pedestrian portable,
qrp
30 Apr 2013
Moorland DXing
Base loaded whip and battery operated FT817 on Dartmoor |
Labels:
devon dartmoor qrp
29 Apr 2013
DXing on the Devon coast
Thurlestone, Devon |
Labels:
devon,
mobile,
pedestrian portable
26 Apr 2013
TJ2B 4 band HF SSB/CW handheld
Reading Julian G4ILO's excellent blog I noticed he mentioned the Youkits TJ2B 4 band HF SSB/CW transceiver from China. The spec of this little handheld looks most interesting with 2 versions covering a choice of 4 HF bands in each option. Available ready built for just $329 with first shipments due around now. A kit version is also available for $269.
Now, at THAT price, this is a much more interesting little commercial unit to climb up that SOTA mountain or clifftop with!
For many months I've been predicting downturns in the Yaesu/Icom/Kenwood sales as a result of the increase in activity from Chinese suppliers. This is surely just the start.
Now, at THAT price, this is a much more interesting little commercial unit to climb up that SOTA mountain or clifftop with!
For many months I've been predicting downturns in the Yaesu/Icom/Kenwood sales as a result of the increase in activity from Chinese suppliers. This is surely just the start.
Labels:
handheld,
hf transceiver,
qrp,
youkits
Using the KX3 portable?
As I prepare for my West Country holiday with my brother next week, I'm amused to see the QST advert for the Elecraft KX3 in use in very rocky terrain. Why am I amused? Well, there is no way that I'd take a "fully loaded" KX3 costing close to £1200 (in UK prices) up a mountain as shown in the photo!
It is OK taking a 12 year old FT817 or a 6 year old VX2 handheld: if these get damaged it's not be a disaster as I've already had huge value from them. But an investment of close on £1200 is another matter.
Perhaps I am not typical, but if I was to spend this sort of money I would not want to throw it in a backpack, risk dropping it on rocks or in a bog and getting battered and scratched. Also, being a very SMD intensive unit, repair is far from easy or low cost.
A better bet for a really portable transceiver to use in SOTA or other portable operations would be a rugged little direct conversion CW or DSB transceiver built into a strong die-cast case, probably for just a single band. It need not look pretty, just functional. Such a unit could be built to give good performance for under £20 buying EVERYTHING new. If dropped, one could easily fix it when back home. If it even got dropped in a bog and irrevocably damaged it wouldn't matter: just build another one!
No, something is wrong if anyone thinks they have to spend £1200 to climb a hill and enjoy amateur radio. I have no doubt the KX3 is a very excellent radio, but it is too expensive (for me) to use in backpack mode.
It is OK taking a 12 year old FT817 or a 6 year old VX2 handheld: if these get damaged it's not be a disaster as I've already had huge value from them. But an investment of close on £1200 is another matter.
Perhaps I am not typical, but if I was to spend this sort of money I would not want to throw it in a backpack, risk dropping it on rocks or in a bog and getting battered and scratched. Also, being a very SMD intensive unit, repair is far from easy or low cost.
A better bet for a really portable transceiver to use in SOTA or other portable operations would be a rugged little direct conversion CW or DSB transceiver built into a strong die-cast case, probably for just a single band. It need not look pretty, just functional. Such a unit could be built to give good performance for under £20 buying EVERYTHING new. If dropped, one could easily fix it when back home. If it even got dropped in a bog and irrevocably damaged it wouldn't matter: just build another one!
No, something is wrong if anyone thinks they have to spend £1200 to climb a hill and enjoy amateur radio. I have no doubt the KX3 is a very excellent radio, but it is too expensive (for me) to use in backpack mode.
Packing for clifftop operation next week
Operating pedestrian portable in South Devon |
For once the weather forecast is cold and reasonably sunny. Usually when I go back to Devon (where I was born and brought up) and it is raining all week my brother says, "you should have come last week - it was lovely".
Labels:
devon,
es,
ft817,
pedestrian portable
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