Wear & tear

Like a lot of cyclists in Britain I’m feeling good about my bike just now. Tatsuro Kiuchi captures the mood nicley. We are reclaiming the roads!
I have put up with a slipping chain for months. The long ride back from Dordrecht to Hoek was the begining of the end for the chainring and I have been riding carefully, keeping the pressure on the pedal just below the point of slip, ever since. Things got too much when I failed to pull away from the traffic lights cleanly and nearly came to serious grief in the process: I got close to damaging my own teeth never mind the chain ring. It had to be fixed! You have to swap the whole  chainring, chain and cassette as a set once things have got to the hooked teeth stage. Not  cheap.  Still I reckon I have had a good few thousand miles out of the metal.With an all new drivechain my bike is a joy to ride;  I can really stamp the thing along now. I’m no Bradley Wiggins but riding a bike is a joy to me! Now I’m able to get my kit loaded up and head off into the wind in search of the heart of the open skies and fen of my home patch. Things got off to a good start with a visit to Fosters Mill:
It was a pleasant ride out, the kite and camera worked well. I got some decent shots of the mill before the wind softened.
The next day the weather was on my side again and off I went to try and capture the lost manor at Landbeach:

The site of the deserted manor and its moat are behind you in these shots. I never got to shoot the site I was after. My radio packed up. By the time I’d hauled the rig out of the sky I got a further 50 or so images like this: I was unable to turn the camera by radio control. I  turned the radio on and off and found the rig would not respond. The shutter release was jammed down and had to be forced off the button. I hadn’t even begun to shoot my subject either.
Nothing to do but head home and see what’s up. Back at the KAP cave I worked through the possibilities, check power supply, check radio mode, check crystals by substitution, check receiver by substitution..no luck..nothing: it’s dead. I don’t know what’s up with it. The LED display is OK, nothing looks burnt or broken inside. Not had it long. Maybe it doesn’t travel so well on the bike?
Fortunately I use generic RC parts so replacements are easy to find, these things can get costly at the top end,  so I took the time to hunt down a basic 5 channel unit. I decided to move up to 2.4Ghz spread spectrum as these are getting affordable now and better still the receivers they use are tiny at only 7.9g. I have been aware there is a great weight saving with the 2.4 Gig system for a while.On re-wiring the rig I found the shutter servo failed to respond. When the transmitter went down it shoved the servo hard over and 50 shots later it burnt out. sigh. I swapped in a spare.
So far so good. Back on the bike (with 2 reels of line , 3 kites, rig and radio)  range tests in a light wind show there’s not a hint of  fall off at 500m down range. Mind you the quoted range for these things (something that is missing from the spec sheet!) is reported to be about 700m
I got the kite up and then hitched the rig to the line. By guesswork I was able to get  the camera pointing at my subject:But there is a problem.  One thing about my set-up that is far from generic is the video relay. It is a 2.4GHz ‘Airwave’ unit matched to a ‘Rangevideo’ receiver, fed from a minicam with its own voltage regulator. It barely works in proximity to the new RC transmitter. The accepted solution to this is to change the video system to a 5.8Ghz set. More bits are required and I will have to re-visit the miss-matched connectors, voltages  and antennae malarkey again. Not to mention the waiting around for deliveries…
The reciever. One thing I learned was that the 5.8Gig channels are available in 3 flavours (A,B and E) you need to have both ends working on the same set of channels (seems obvious but if you buy a transmitter on ‘A’ band it won’t talk to a receiver on ‘B’ band and vice-versa). I got an ‘A’ channel one from firtstpersonview.co.uk and began to experiment with its power supply. It’s helpfully labelled  ‘6-131v 250mA’ so I began with a 6v2200mAh Ni-mh battery pack:
It ate that in about 40mins. My next option is an 11.vLipo. It is a nice small unit and it fits on the RC controller with a velcro patch ok.
The transmitter for 5.8Ghz came as a board, fortunately for me with a set of connectors to fit it. Unfortunately it has a minimum voltage requirement of 7 v. My rig is powered by a 6.6v LiFe battery to meet the max voltage for the video camera. I’m not sure how much power the new frequency will use but I suspect I’ll have to up the rig power towards the 9v maximum quoted for the receiver.

The birds nest of wires connects a jack socket for video in, Futaba power fly lead in and (an unexpected bonus, I can supply the video camera with this) a regulated 5v out socket. For now I have left out the Gent Altimeter board until I can find a box just small enough to fit both boards and the tangle of wires in.
More testing reveals 2 further unexpected problems. The power consumption of the 5.8Ghz unit is hefty, I drained the rig battery in about half an hour waiting for trains and ended up shooting this blind:
and I had already missed the several trains discovering the new transmitter has a ‘rate’ switch which makes the shutter servo fail to reach the button when its set  to ‘low’ pah!  6.6v is clearly not enough to power the new set up so I’ll have to find something close to a 9v supply or resort to adding a UBEC (more weight)  to the rig as a voltage regulator.I replaced my ally chainring with a steel one in the hope it will last. Let’s hope replacing 35MHz with 2.4 GHz will last too!

About billboyheritagesurvey

Heritage worker
Gallery | This entry was posted in KAP, Windmills and tagged , , . Bookmark the permalink.

10 Responses to Wear & tear

  1. Jonathan Turner says:

    You should be able to negate the effect of the rate switch by selecting 100% travel in both positions. This way if you accidentally knock it there will be no negative effect.

    Jono

  2. Ramon says:

    Must have missed this topic, Bill. Thanks for linking it from flickr. Do you have the transmitter details for me to look into? Maybe I can find something that might be of use for you.

  3. Ramon says:

    Good solution! I didn’t know you were running both the RC RX and the video link TX from the same power source. That is a guarantee for trouble. I totally separated it by giving these two devices their own power supply. The videolink TX is now fed by 1x AAA cell and a VPack power booster which converts the low voltage to a usable 5 Volts output. Very lightweight so perfect for the job.

    I saw the pics you made today. Good to read the solution you have is working great too.

    Ramon

    • You have a neat solution too Ramon. What’s the video runtime you get from a single AAA cell? I’m using hefty 11.1v 3s LiPo packs to keep things live for a few hours. My rig is 840g now so cutting the weight would be good!

      B

  4. Ramon says:

    When I use a rechargeable 1.2V AAA, 1000mAh it takes hours to drain it. The total current that is drawn from it is about 50mA. So if you need or want to lose some weight here and there, that’s the way to go:

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