The £20 DECENT HF transceiver challenge

Ideas for the £20 (or less) new HF transceiver so far, based on past experiences:

• 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

Is anyone else up for this challenge? The target is a really credible HF transceiver with decent, not compromised, performance that can be made with all new parts for less than £20.

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.

Back home again

Well, the week long holiday in South Devon is over and we are back home in Burwell again. The portable HF operation was very successful and enjoyable, operating from a mix of locations, mainly clifftop sites with excellent take-offs across the sea to the USA, Africa and S.America.  Average QSO distance with 2.5W SSB was over 3000km, with several QSOs with the USA and Canada on the higher HF bands using just 2W and a short base loaded whip.

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!

Farmyard DXing

A carpet of bluebells on a Devon woodland walk today

No radios out on our walks today, but a quick session outside my brother's house netted a couple of 2W SSB QSOs with Europeans on 15 and 12m.  Will have another clifftop mini-DXpedition tomorrow before we return home to East Anglia on Saturday - no real hills, miles from the sea, higher noise floor, bills, phone messages.....can I stay on holiday in this glorious sunshine?

More seaside DXing today

Location today at Rock House beach at Thurlestone, Devon

Today I was busy visiting National Trust places with the wife, but managed a little DXing on the Devon coast again. Lots of DX on 15,12 and 10m SSB with some choice ones in there. All I managed was a 51 report from Madeira Is on 12m SSB with the 2.5W from the FT817.

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.

Moorland DXing

Base loaded whip and battery operated FT817 on Dartmoor

With 2.5W SSB and the short vertical on the car I had more fun today, this time from some high spots on Dartmoor in Devon. I caught my first 6m Es opening this season with a nice 2.5W QRP QSO into Sweden. The best DX on HF was a QSO with W1HI in Rhode Island which turned into a 2-way QRP QSO when Ed reduced his SSB signal down to 2W to match mine and we carried on a perfect QSO! Other QSOs on 15m included Morocco, Sweden and several Russians. No great DX - I was again unable to beat the pile-up on ZD7FT and the D44 station - but a good enjoyable time was had in the sunshine. In the morning there were lots of Japanese SSB stations coming through, but none worked.

DXing on the Devon coast

Thurlestone, Devon

This afternoon I enjoyed the beautiful coastline of the South Hams of Devon whilst doing some operating with the FT817 and a small HF mag-mount on the car. There was plenty of choice DX around including 8Q7, ZD7, FM5, HZ, CE and CX although I only managed to work W, VE, UA1, SV and a few others with my 2.5W SSB in the time I was on. Tomorrow we will be on the top of Dartmoor and I'll try to work a few countries.

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.

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.

Packing for clifftop operation next week

Operating pedestrian portable in South Devon

Next week, I am off to South Devon to stay with my brother for a few days. This time, I am packing some equipment to operate /P and /M (static only) from some prime clifftop and moorland sites with excellent take-offs. With me will be the FT817 and little VX2 together with whip antennas from 15m to 70cms which can be used on the rig or on the mag-mount. As the sporadic-E season has started, there is a good chance of working some Europeans on 6m and 10m. There is an outside chance of some Es on 2m if I strike lucky.

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".

More eBay items for sale

http://myworld.ebay.co.uk/rlapthorn

As part of our de-cluttering session before we move, I've listed some more items on eBay. This time it is mainly new or nearly new children's clothes, a couple of women's clothing items (tops) and a couple of non-radio books. All the clothes items are in very good condition (some are brand new) and these may be of interest to the XYL or YL.

The Galapagos book cost £18.99 and is in MINT condition. 

The Cinema of Isolation book is a very interesting study about how physical disability has been portrayed in the cinema over the last 100 years showing how attitudes have changed.