Mr H in Yorkshire

Jansky was the scientist, his 'scope' had no name, it looked like a fairground ride with wires, But who knew before that about radio waves from space? Need 3 eh, in that case Palomar 200inch and Gaia.

Karl Jansky, 1932 the first discovery of radio waves from space?

Not the advice you want maybe but you did ask for other options. The app 'Skysafari' on a smartphone and a reasonable pair of binos will go a long way to getting you started, as well as helping you learn what's out there. It is too easy to spend a greater amount of money and yet be disappointed because your investment does not yield the expected results. This is because expectations can be misled by seeing all the amazing photos that are published, most of which have been made on multi thousand pound rigs.

If your astronomy involves sitting on a chair of any sort you may be interested to know that Sainsbury's garages are selling electrically heated car seat covers, switchable 35/45 watts, £15 a pop. Immediately bought one.

Hi tenby2, I have only recently joined this forum so my reply is a bit tardy. Have you sorted your mount problem yet? I have a set of Helios Quantum 20 x 100 which I can use in a parallelogram mount or a DIY GOTO drive made from a hacked Ioptron Cube, (description posted recently). To minimise the load on the drive I finessed the balance of the binos with pieces of lead sheet fixed discreetly with silver tank-tape. With care It is possible to get a very close dynamic balance, which would lessen the burden on the thumb screw (which look somewhat poorly suited to the role).

I am entirely pessimistic about any return to darkness. When I moved to my small Dales town in 1988, getting home from work I could get out of the car and see the milky way! Now all I see is the stark shadows and glare from the all night security lighting on the school opposite, the social hall next below me on the hill and worst of all, the AONB office across and up the road. This area of outstanding natural beauty is not so at night but my polite letter, after they had installed the lights, never even got a reply. The policies that result in these lighting installations are stupid and insensitive - security lights in an area that literally has no crime. My only good fortune is having a very good dark site 30 minutes drive away but I do regret the way things are.

As a lockdown project I hacked an old Ioptron Cube to make a 'goto' drive for a pair of 45 degree 100mm Helios Quantum binoculars. I fixed 3/4" bearings into the threaded mounts, on one side sandwiched by steel 2" plates. The bearing rotates freely while the plates are fixed to the binocular body. The outer plate has a peg in its centre and another towards the periphery. I separated the Cube into its two drives and attached a steel 'L' shaped fork with open sockets to the azimuth drive. The fork arms are offset so that the eyepieces stay clear of the azimuth drive when vertical. This also keeps the fork arms short, I tried a longer fork positioned centrally, although no counterweight was then required, the fork oscillated badly if bumped. The binos attach to the alt drive via a magnetic clutch, the pegs slot into the outer clutch plate. The magnets are strong enough to slew and track, but if bumped or obstructed, and for initial alignment, the binos can move. Because the binoculars are supported in the fork, the altitude drive takes no load at all, it merely serves to effect rotation. I finessed the balance of the binoculars with small lead weights to further reduce the demand on the drive and avoid any unwanted clutch slip. The offset 16lbs weight of the binoculars is counterbalanced by a 20lbs lead weight. Withh this arrangement, even though the load on the azimuth drive is way beyond Ioptron's specifications, it slews and tracks without any problem. The setup is controlled from an ancient 32-bit notebook PC running Stellarium, it's perfectly adequate for the job and being 12 volt can share the battery needed for the Cube mount and the home made elevating pier. To maintain the eyepieces at a comfortable height as the binoculars are moved from low to high angle targets I have made a poor man's elevating pier which uses drawer slides and a linear actuator with a 20" extension capacity. I've managed to suppress rotational oscillations by adding stiff rings to the slides, movement dies out in less than 2 seconds, so not too bad.

Hello garryblueboy, I see you use an Ioptron cube pro, I like their cube mounts too. You have inspired me to post a description of a cube hack I made some time ago. I'll post in the 'Mounts' section as that seems more appropriate and it was daytime!

Hi Rusted, from a old friend of mine who had a sizeable scientific equipment company I understand that existing and known 'inventions', even something as simple as a screw threaded rod, if used in a novel situation, could be patented, so the 4-bar linkage, unless already patented or registered as prior art in some way, qualifies. However, making the design universal needs a whole engineering study and would probably require all the up/down in/out adjustments that I wanted to do away with. This chair is designed to fit ME but wont fit someone 6' 6" or 5' 3" because their pelvis to eyeball distance is different. It can be adapted, I actually made the seat base up/down adjustable initially but then thought why bother. I could probably overcome the engineering issues but there are so many complications , let alone an investment way beyond my means, involved in making a business product hat it just is not worth it to me. PS my son has given me back an original PST that I bought him for his 18th, I'm going to parallel mount it with a very old 90mm meade SCT with solar filter for H alpha and white light viewing. All that's needed is some daylight, the Yorkshire weather has been vile for weeks now. Is this atlantic weather clouding you out too.

Hi there, Thanks for that but I am much happier to share this design in the community than try to commercialise it. It costs a fortune to patent something and it would require a substantial engineering analysis and there are numerous other complications involved, just not for me. The only real innovation is the 4-bar linkage and anyone can use that.

Hi Grumpius, it's on my to do list. I thought about breaking it into two for file size. One of assembling and connecting the parts and another one just driving it around. My grandchildren love riding in it too! I can't say how soon because my poor wife has just broken her arm and we are a bit preoccupied. Cheers

To any that I have not messaged my thanks, being new to this forum I did not understand how to respond directly to comments, I don't want to give the impression of ignoring anyone. I am glad the chair design has been so well received, any ideas involved that may help other constructors, you are most welcome to adopt and adapt. After Christmas, when I have some spare time I will post a video of the chair in action. Happy Christmas.

Thanks for the appreciative comments. It has been very satisfying, firstly to analyse the problems in 'traditional' binochairs, and then to find a solution. I originally thought up the linkage usage 15 years ago, at that time I had an full suspension bike and the rear sus uses the same mechanism. It's taken a while (and much metal cutting) to finally create.

Over the years I have struggled to use my 100mm aperture straight-through binoculars for high altitude targets. On a tripod or even a parallelogram mount high elevation viewing is literally a pain in the neck, but the bulk and 20 x mag really demands some form of support. The solution is an alt-az binochair. The ultimate purpose of a binochair is simple: to enable the observer to comfortably keep their eyes at the eyepiece sweetspot in any chosen part of the sky. I have made (and abandoned) 3 chairs previously but I have gained a clear idea of the problems in the existing body of designs. The problems Body weight redistribution: A rigid seat has an included angle of 100 degrees or so. When used for high altitude targets, as the seat back approached horizontal, the bodyweight redistribution made me slide upwards and my knees want to meet my face. On a lounger seat with the back lowered enough for zenith viewing, I found I would slide down relative to the binoculars. There is also the risk that if the centre of mass moves too far out of balance the chair can topple over, as has been reported. Viewing alignment at different elevations: The axis of the skull's pivot on the spine is about in line with the ear lobes. Unless the pivots of the frame holding the binoculars coincide with this, the eyes and the eyepieces will follow different arcs. The mismatch does not have to be excessive before needing to adjust the bino's up/down and possibly fore/aft too. It occurred to me that if I could 'wear' my binos as if they were my glasses, the adjustments would not be needed. Could this be possible with something that weighs about 16lbs? The key elements of the design. 1) The frame which carries the binoculars also carries the head rest, the observer's head does not touch the seat back. The frame is made to pivot about the head/spine rotation axis as exactly as possible - a position found by videoing my head nodding up and down. 2) The seat and frame are mechanically connected by a 'four-bar' linkage (see diagram below) so that as the seat elevates, so do the binos. Importantly the linkage is arranged so that as the seat elevates through 45 degrees, the frame also moves through 45 degrees relative to the seat. For the observer, the binoculars move from horizon to zenith for a head tilt and a body position change of only 45 degrees. Limiting the movements to 45 degrees avoids any problematic bodyweight displacement, and doesn't strain the neck. The head rest provides constant support through to the zenith and maintains the head in exactly the right viewing position in any part of the sky. I also balanced the user/seat/binoculars setup carefully, by temporarily locking the binos at about 45degrees and climbing aboard while the setup was suspended at different points along the frame, using a plumb bob to find the c.o.g. As the rig is balanced like this, there is no need for counterweights, springs/bungees or outrigger legs. As there are no 'on the fly' adjustments, the seat construction is clean and simple. The entire rig was designed from the start to be easily transported in a old Yaris, cars don't come much smaller than that. The seat sits onto trestle forks (alt axis) that are hinged to a base frame. The 4-bar frame to seat connectors fit over short pins on the fork extensions. The fork unit locates on a 'ground ring' comprising a bicycle wheel (azimuth axis) fixed to a hollow steel ring beam with adjustable legs. The trestle locks on the hub with the quick release skewer. The altitude drive, a butchered linear actuator, and the azimuth drive are both rapidly detachable. Near the ends of the fork legs are hard nylon rollers which ride on the wheel rim and take all loads directly to the ring beam. Despite using only 20mm box section steel in the forks, the overall structure is such that any disturbances are damped within a second or two. For transportation, after the binoculars have been removed, the altitude drive and seat-frame link arms are unpinned and the seat is lifted off; the forks are folded flat and the fork unit detached from the ground ring. The seat base and the bino/headrest frame fold in against the seat back, compacting the chair. It's not quite IKEA flat pack but it all fits a very modest sized car boot and the operation takes only a few minutes. The binochair motion is controlled by a joystick switch unit and can be driven freehand, or directed to selected targets using encoders. The altitude encoder is mounted directly to the binoculars and is actuated by a pendulum. The azimuth encoder is offset from the wheel hub on a sprung arm and is connected by a toothed pulley and belt. The encoders and interface comprise the electronics part of the 'DobsonDream' DSC kit from AstroGadget in the Ukraine. The disassembled binochair in the car. The ground ring/azimuth drive. Folded altitude forks attached to azimuth unit. Alt Az unit opened. Seat attached to alt az unit. Frame/seat link arms attached - binochair fully assembled. Seat elevated (4 bar links colour coded) Binochair design condensed.rtf