Minimum QRP: Doing more with under five watt amateur radio (Peter Parker VK3YE, Kindle)

I’ve been meaning to get a copy of Peter VK3YE’s e-book ‘Minimum QRP: Doing more with under five watt amateur radio‘ for some time, and a string of in-conversation references to it by Bill N2CQR on Soldersmoke prompted me to buy and read it this week. I had thought Peter may have made this a book of celebration of radio homebrew culture, a kind of personal homage to thousands of soldering iron hours, something along the lines of the groove created by Bill and Pete on Soldersmoke. But it is a broader offering. The book is a compendium of amateur radio notes, observations, tips and tricks from a dedicated experimenter, maker and operator. QRP is the common thread. Peter has found a balance that avoids it being only a homebrew/DIY manual or a personal memoir. It occupies a different space from his website and Youtube channel, which tend to open up his projects, antenna escapades and circuit design ideas. There is something in it for all amateur radio enthusiasts, not just the homebrewer or dedicated QRPer. The writing is grounded and pragmatic, and most of the content is illustrated with stories or examples drawn from the author’s experience.

Because I’m recently keen on SOTA, some of my favourite sections involve QRP portable operating. On choosing a suitable power source for a 5 watt radio, Peter opens up the considerations in full. As one who has stood in an electronics retailer doing mental calculations of how long a particular battery would  power my QRP rig on a summit, this material was told story-like and with reference to real rigs. Assume the listen-to-talk ratio on your typical QRP portable outing is about 3:1. Taking the Yaesu FT-817 as a reference, receiver power draw is 0.4 amps, transmitter 2A, so power consumption over time is 0.4 times 0.75 (0.3 amp hour) for receive and 2 times 0.25 (0.5 amp hour) for transmit. Add them, and you can predict that a 0.8 amp hour battery will last about an hour. While perfectly usable for an afternoon outing, this, Peter notes, is too high for a multi-day off-grid camping or hiking.  That a 100 watt transceiver wound back to 5 watts comes in at 2.5 amp hours, three times heavier power draw than the 817, is further reason to discount this option for serious QRP portable work. Compare this with Elecraft’s KX-1 trail radio, at 40mA on receive and 0.5A on transmit, which will loaf along on a 2 amp hour battery for up to 12 hours. But even this is heavy compared with the classic QRP designs of Doug de Maw W1FB and Wes Hayward W7ZOI on the 1970s.

There is an attention to detail borne of experience. ‘Transceivers with long and thin power cables are prone to voltage drop between it and the battery. Better QRP rigs have an indicator showing the voltage at the transceiver’.  Look for dimming dial lights at high audio levels or on transmit. To conserve power, use earphones rather than speaker audio, switch off or disconnect dial lights and displays. Don’t use speech processing.

In the chapter on antennas, the features of dipoles (coax-fed, open wire fed, off-center and end-fed) are covered. Verticals, loops, and other variants are summarised. This is a useful refresher and serves to confirm impressions formed over the years. The feature of this material is a section on ‘antennas to avoid’ — dipoles shorter than 3/8 wavelength at the lowest operating frequency, short verticals, short verticals with small ground systems, anything that claims small size, wide bandwidth and high efficiency.  This advice, clearly borne of experience, reveals Peter’s objective — to make QRP a positive experience, a bit of fun, and never tiresome.  If I remember only one thing from this chapter it will be the old adage:

It is hard to make an antenna that’s much better than a dipole but very easy to build one that’s inferior.

That statement sums up many dozens of hours I’ve spent tinkering with antennas at times over the past 40 years. I decided a long time ago that one life is not enough time to master both building QRP radios and antennas. Standing at that  QRPer’s personal fork in the road, I elected to build the radios. As a consequence, all my QRP rigs get connected to a dipole most of the time, whether at home or on a summit. And mostly, it’s a quality (fit for purpose) antenna.

As the chapter morphs into Peter’s personal quest to perfect loops and verticals for pedestrian mobile it acquires a narrative feel and demonstrates a sense of quest. At one point his ‘pesky trailing counterpoise’ had a nasty habit of attracted dogs and snagging in seaweed. The solution was to wear an aluminium ankle ring and walk ankle-to-knee deep in the water (in a wet suit on cooler days), thereby leveraging the operator’s lower body as earth rod. If you try this on your home beach, Peter cautions, don’t exceed 5 watts to avoid the possibility of RF burns.

Coverage of the features and suitability of each amateur band for QRP operating, making contacts and DXing is comprehensive.

Pile-ups on any of the DX bands can be difficult to break. [Amen!] Sometimes you can leave empty-handed. [Most times in my experience]. One theme with QRP DXing is to avoid competition. One way you can do this is to scan the bands listening for stations tuning up and starting to call CQ. At this point few people will be monitoring the frequency or in a position to call. And, if rare, they won’t have been spotted on the DX cluster yet.

Peter’s line of advice is most effective in the chapter on operating. Thinking of frequencies as hot, warm or cold depending on current or recent activity, and coverage of CQing, hunt-and-pounce, tail-ending, net-iquette and the like, is about the most useful and practical advice a new operator could get. While we all work this out sooner or later, the predominance of new F-calls and the experience of listening to a debutante’s clunky first on- air steps makes this content most timely. It is a welcome update to the only source of operating practice guidance I remember, the ARRL Handbooks of the 1970s. This chapter is recommended reading for all Foundation and new licensees.

Contests, awards, working portable, pedestrian mobile, milliwatting, VHF, UHF, satellites, blogging, pod-casting, Youtubing, digital modes, it is hard to think of a topic that doesn’t rate a mention. All boxes are ticked. But it is the spirit of participation in QRP that stands out rather than the comprehensiveness of the coverage. On his Youtube channel, Peter has a video titled ‘Making the Pixie slightly less appalling’. He takes aim again in the book:

Much of QRP’s appeal is achieving great results from simplicity. But don’t overdo it. Yes, Pixie, I’m looking at you! The lightness of minimalist single-frequency rigs can be beguile the newcomer. However the ensuing fruitless calling soon demonstrates that bare-bones rigs are better talked about than talked with.

Reading Minimum QRP helped me understand why Peter dislikes this rig and anything that swings too close to a gimmick. The essence of QRP is communication. If a crystal locked tiny-powered matchbox doesn’t let you make contacts reliably it is counter-productive. Pixie gets harsh treatment because a few disappointments can lead to abandonment. And in a world of digital maker communities, DIY Internet of Things and consumer electronics, the amateur community cannot afford to disappoint newcomers or new returners. To that end Minimum QRP makes a valuable contribution to doing QRP as a primer and an on-ramp for prospective and lapsed enthusiasts.

Now, it must be time to go and check if 7090 is warm.