Showing posts with label low cost. Show all posts
Showing posts with label low cost. Show all posts

18 Sept 2017

Low cost amateur radio

Many times I have said that you don't have to spend a lot to get fun with our hobby. WISPY is just one example, but there are many.

Some choose to spend huge amounts on rigs, linears, towers, rotators and beams. Each to their own, but this is not for me. I am sure many newcomers are put off thinking it is an expensive hobby.

With QRP and simple, low, wire antennas I have worked the whole world with less than 10W SSB. DXCC? Well I have lost count, but it is way over 100!

4 May 2013

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.