In many human endeavours, performance improvement arises through the accumulation of a run of small gains over time. No one gain seems particularly important, but top-performers tend to be those who ‘bag’ each and every small gain as it comes along.
For the SOTA Activator, the question of whether to carry a coax feeder heavier than RG-174 often comes up.
The table below summarises the numbers for a notional 10 metre line.
Preferring RG-58 over RG-174 seems to require an additional weight of some 270 grams to be ‘lugged’ up the hill.
Whether this justifies the 14MHz loss-reduction of some 0.5dB is a matter for each Activator. But remember the incremental gains argument. A lower-loss balun or ATU might offer a further 0.5-1.0dB, a different antenna choice another 1dB, and so forth.
In cycling, people often ask: “What is the most cost-effective way to improve performance on the bike?” The sage reply is always: “Reduce the weight above the saddle!”
Similarly, for the SOTA Activator, there doesn’t need to be any weight increase when moving up to 10m of RG-58.
A week off the pies and puddings should readily deliver the 270 gram reduction required to achieve ‘net zero’
Should he/she persist for say a month, then ‘net zero’ with 10m of Mini-8 hoves into view. You get the idea.
73 es HNY
Dave GM4EVS
PS Over the holidays, some may have wrapped the equivalent of 10m of RG-213 round their waist. They have rather more work to do
I mostly use RG174 because it is much easier to handle than RG58 - it will wind on a figure of eight winder easily. I do have 3m of RG58 in my activation kit but even that is awkward to deal with especially in cold weather. I carefully wind it in a circle to avoid kinking. Any longer and it’s a right pain.
I even use RG174 for 2m. On FM the extra loss is not really worth worrying about.
Engineering isn’t about producing the best but about the best compromise between competing factors such as quality, cost and convenience.
Fair comment - 270 grams is very little extra to carry, probably worthwhile for 6/10/12/15m operation but you probably won’t notice one (s)iota of difference on the other HF bands. When the 2024 10m Challenge started I made up a “flowerpot” end fed dipole for the 10m band using RG-58. I tuned it in the garden for perfect SWR on 10m but never used it due to the extra weight of the coax wound on a piece of Open Reach fibre cable duct, around 50mm diameter I think. I wished I had used RG-174 then I might have tried using it, but I didn’t have any in my spares store… Instead of using the “Flowerpot” I made up some lightweight OCFD dipoles and they both worked very well for me on the 10m band during the first half of the year.
As Richard @G4TGJ said convenience if of great importance in SOTA for sure.
A 4 finger Kitkat weighs 41.5g in the UK at present. Saving 270g on coax allows an additional 6.5 Kitkats to be taken on the activation. Obvious what the action should be here.
