Carbon Brush

Ah but is there a grain of truth behind our tales of woe? Is there more cloud, or more water in the air, or more thermal instability (on long term average) now we are experiencing climate change? Or is it that when we bought our first scopes we would go out as long as there was a little point of light somewhere for a few minutes? Now we look up and don't bother unless it is something special?

There are a few objects that don't come around time after time, or are time limited. Comets are the obvious example. Halley is a predictable once in a lifetime. Others I have seen were on the first pass since telescope invention. Near earth asteroids we can ignore. If they get big or bright enough for amateur viewing, maybe it is time to take cover🤣 Anyone wanting a photo of the ISS with a shuttle alongside. Sorry, that photo opportunity has gone. But other craft do visit. I consider myself fortunate to have viewed both Venus and Mercury transits. Then the 1 in 400 years (I think) Saturn/Jupiter conjuction. There is always something to see. It is just a case of knowing what is around at this time of year, or how the planets are placed. Then of course if you are able to travel overseas to a different latitude, the sky is so different. I was completely lost on a holiday near the equator. Polaris was useless as a pointer, being almost on the horizon. But all those (unseen by me) southern constellations. Wow. I like to think about viewing plans based on what is going to be around, rather than having specific targets.

Last night I wanted to try my 'Talwatcher' hybrid scope with binoviewers. I had established the ability to focus without resort to barlow in daylight. But wanted to try night use. Rain showers all day and expected to continue in the evening. But some stars were visible. Venus was shining brightly in the west, nicely placed to view from in the conservatory, with the door open - I was ready for the rain. The seeing was awful, changing by the second. I could sometimes make out the phase. But the binoviewing worked. Advice to self and others. Don't try to view a low target when the sky is known to be unstable.😁

Well the company exists, as does the CEO. However, web page aspirations and projects that fly are often very different.

Solar panels from the like of Amazon are very much over sold on their abilities. In practice your home panel is fixed so it only faces the sun head on, once each day. At all other daylight time, it has lower output. Then there are clouds. Then they degrade with time - a few years. Then there is risk of seals failing and letting in rain on cheap panels. Whatever panels you buy, talk to a specialist company. They will offer you choices and know to avoid product that causes problems after sale. A bit like the advice about buying astro kit from amazon and the like, or an astro retailer.

In times before affordable lasers, I always used a cap/cheshire. These being upgrades on a 35mm film canister with a hole poked in the centre. These days I really like a laser on almost any scope. The dot movement is very useful when racking a focusser in/out to porve it runs true, or when applying gentle pressure to things. It shows you where things are not right, or wobbly, or loose. Then there is the question of whether your arms can reach everything while looking down the eyepiece tube on a big scope. All the tools have their place. Somewhere I even have a book (albeit a thin book) about collimating newts. Not just the single page, or even couple of paragraphs description we normally think about! As long as you get decent views, don't worry.

Come on sign up!!! https://petition.parliament.uk/petitions/632558 You may not agree with the exact wording, but this is an opportunity to get the ball rolling on a national level, instead of every individual having to argue their case. There are THOUSANDS of SGL members, and potentially millions of people insterested in a dark sky for other reasonas. But only 570 signatures at present.

You beat me to it😄. Another big lump passing close by, discovered only recently.

The link is https://petition.parliament.uk/petitions/632558 May help avoid searching. Signed of course. I am 213 - where is everyone?

Ref the B&Q trolley. Not recommended. We use this type at work. They all come from China with different badges. The handle folds down onto the base. so modification needed to free a dob. There two fixed, and two swivel castors. Not good for a restricted space. The narrow wheels and solid tyres are fine on smooth hard surfaces only. The base is made two steel sheets pressed together. It would be difficult to add jacking/levelling screws etc. without adding a base plate. Sorry to pour water on the enthusiasm of anyone who may be thinking of buying this product. If you want to carry some boxes. Or shift a heavy item they are fine.

I saw the Tuff Truks at Kettering. I thought them very well built, and well thought out.👍 The frames are welded heavy gauge mild steel, powder coated. Most (if not all) the fixings are stainless. These people will customise the truks for you. They had a couple with modifcations from standard. The only cheapie bit was the tyres/wheels. Just like those on my garden cart. But I know from experience when they degrade after a few years, they are cheap to replace. Having said this, the garden cart gets left out in rain to wreck wheels and sun to degrade tyres. So unless you choose to abuse the scope by leaving it out, the tyres and wheels will last for many years😁 For a short time I owned a JMI trolley. From memory of a few years back I would say the Tuf Truk is as good or better. I have a 12" dob and wheels of some sort are in my view a must have. Whether trolley, sack truck construction or something else. Currently the dob is on a home build base. An old desk top and castors. It was a quick build at zero cost as I already had the materials. Fine for smooth concrete but no good to wheel over grass. HTH, David.

I have never used a Quark. Only a couple of PST & LS60 so not an expert opinion. Free advice is worth what you pay, etc. I have seen internal reflections in otherwise good eyepieces, though these are obvious by their movement when you move the scope a little. To me your 'fibres' are very well focussed items somewhere in the optical train. Are you able to put the Quark in a different scope? I'm thinking here that by using different lenses either side of the Quark, you may an idea of the conditions to cause the strange effect. If you conclude the Quark is generating the problem, you are in a position to ask the retailer to sort it out. HTH, David.

Thank you for an excellent post. I never realised it was such an interesting and active place. How different to the world in the 'Expanse' story on Amazon TV. How different to book I read over 50 years ago. A mission to Ceres that had an in flight problem. I'm sorry I don't remember the title - actually I have not thought about the book for decades! The crew got there, but were stuck. No mention of tiny gravity. An ocean was mentioned. Actually the ocean produced enough seaweed for the crew the construct a huge arrow pointing to their stranded rocket. I believe it had a good ending but I don't remember the details.

By all means try a few thousand uF for the bulk storage. It is easy to get carried away trying to overdesign when you don't know the reactive load, or the PSU characteristics. But actually having a PSU with a main output 12V (or a bit more) is a much better idea. I use a TDK DIN rail mounted supply, screwed to the wall with a cover over the mains terminals. Other brands and mounting methods are available😄

In a lot of PC type power supplies, the 5V (high power) output is well controlled. The 12V output is not well regulated and relies on a certain load on the 5V provide a sensible output. This is probably where your mention of resistors comes into play. I don't think the problems are voltage drop as such, but the PSU not responding well to the reactive load of long cables. The designer was thinking in terms of a few cm within the PC case. In my observatory I use a decent (not PC) quality supply generating about 13.5V, mounted on the wall. This connects to the AWR motor drive on the pillar. However, at the pillar I have electrolytic bulk + suppression capacitors. These were included on day 1 as a precaution. Never had any issues. HTH, David.

I agree it is a good idea to use your own site for products. I don't have much hope of the auction site controlling things. If the seller is ripping off work, what is the quality of the poduct? Does he understand the print quality required? My Bahtinov masks are all from 'proper' astronomy sources. They are the correct dimensions and have good print or machining quality.

I missed the early S@N programmes because they were past my bedtime and video recorders had not yet been invented. As the years passed I could stay up later then I had the Sony Betamax machine for the programmes that I missed. Unfortunately in the past couple of years the show, in my view has gone downhill. Despite the ease of BBC iplayer to catch up I find myself looking only if there is nothing else to watch. Is it because my knowledge has improved (quiet at the back, stop sniggering) over the years and the show still targets the same knowledge level? Is it that the audience demands a show that is more about visual effects and presenters with backgrounds? By that I mean for example SPM at a desk with cardboard cut out planets vs Brian Cox wandering around mountains and deserts. Today we can find a lot of the S@N technical content online, rather than having to wait for the monthly show. Therefore the show has to be about the the presenters and the backdrops. No easy answers.

Moving on now to the important air transport approval. This multi page document the describes onerous test procedures and their outcome. Basically you abuse multiple battery packs in all sorts of ways and ensure it does not cover you in noxious chemicals or catch fire. The equipment is reported to have passed. Issued in 2019. However, the manufacturer (and applicant) name is Yabo Power, not Talentcell. But an email contact has a Talentcell email. The photos in the report look like the Talentcell box. But that is the plastic box. In conclusion. This report probably refers to the talentcell product on offer. However, they should really be updating and tidying up the paper trail for UK or EU import. If you want to take this product on a plane, the conformity certificate probably carries more weight with non technical and approvals people. Essentially the border makes it look good and it is a single page. The UN approval really is what they should be looking for but it is multi page and part chinese text! YB1208300-USB UN(1).pdf

I have received a reply from Talentcell about their certification. Starting with the declaration of confirmity. This document means it is entitled to carry a CE mark. The tests solely EMC related. In laymans terms - will it cause interference to other electronics, or will it misbehave when near other electronics. The test house has tested one sample. But claims the certificate to cover several products. One of the standards is obsolete. The name 'Talentcell' is not used anywhere in the test report. Only a part/model number. The applicant is named as a different Shenzen company. The test date is 2015. This means if the product has been changed in the past 8 years or the individual who signed the certificate is no longer in post, a new certificate is required. I note there is no safety testing. However, this is probably covered by the transport certificate. Bottom line. It is probably OK. But if a container full of these arrived at the dock, trading standards have enough grey areas in the paper trail to hold it up. However, it does give the impression that something like this was tested. If I was buying lots of these for my work, I would be looking for much more evidence of compliance.

This reminds me of something we used to do at work. Back in the days when electronic components were large enough to see! A supplier always had a stand at shows with a big jar of components. Guess how many capacitors to win whatever it was. We did not have any clever component counting aids so grew used to estimating handfuls, etc. It is also possible to estimate the contants of a sweet jar by looking at it for a couple of minutes and getting a feel for width/height. Often 3 or 4 of us from work would visit the show. We never won. When the rep visited us in the weeks following, he would bring the scores and always commented on how near we were to the actual number. But we never let on our technique😄

I am following this thread with interest. Particularly the Talentcell pack. I have requested a couple of the statutory documents from Talentcell. These cover the CE mark, which it must have for UK/EU sale, and the status of air transport approval. It will be interesting to see what arrives.

I did something like this a few years back. Sorry no photos. I used a piece of aluminium bar about 20mm thick so it would take screw threads. To me it was a near enough zero cost solution as I had the bar and tools to drill/tap. HTH, David.

Hello Jennifer and welcome. You already know £100 is pushing things for a new scope that gives worthwhile views. The problem with buying used is where to get a decent scope. The advice is always to avoid ebay, gumtree, etc. You can easily end up with broken junk. You have the time to search. May I suggest you and your son post on SGL and continue to read - and ask questions. When you reach a post count and time on SGL (I forget the number) you can view the 'classified for sale' section, which is currently invisble to you. This is where you will find used equipment with an honest description of condition. Much of my kit comes from there. In December I sold a TAL reflector scope on mount with eyepieces for £100. That would have been an excellent scope for your son. I mention this as an example of what can be had from a reputable used equipment site. Then when your son gets his scope, the questions will start in earnest, and the accessory spend. SGL can help again. Keep asking the questions, David.

On airline battery limits. It is actually a bit more complicated. There are limits on individual passenger carrying. But there also a limit for the aircraft. I don't remember the details. Worst case would be 100 astro enthusiasts carrying 100Wh of lithium each and it would be no go! Consider a 'business' flight with 100 executives carrying laptop computers vs a 'bucket and spade' flight with mainly phones. It is the total hazard/risk, as well as individuals, that the rule makers are interested in. Whatever you decide to take, include the paperwork. The battery packs should have a UN transport approval, stated energy, and manufacturer contact information. Also take a printed copy of the IATA allowed limit, and airline limit, from their web sites. If you don't have this information, you could end up with a 'no' from the airline and no evidence to support your claim. Oh yes. Bring us some nice pictures😁

A problem I have seen. Some years back a colleague sent a repaired item to the US from the UK. There was a threshold on cost where you went from one wheelbarrow of paperwork to two wheelbarrows. So he declared it below the threshold. That was a parcel the carrier happened to lose, so paid out the low value. Another issue is that you need to read the small print on carrier insurance. Some years ago TNT used to consider anything for repair as worth nothing more than a few ££ per ton scrap value. A UK customer was sending us a £5K item for a (known by us to be <£500) repair. The TNT truck burnt out on a motorway - losing the entire load. TNT paid our customer something like £50. The customer then had to pay us £5K for the new equipment. Carriers will happily take your parcel, and the insurance money, but not pay out. Not forgetting of course a telescope contains glass that many carriers won't pay out on. They don't discriminate between a chandelier, set of goblets, or telescope with lens in a cell. In my work, for around 20 years we have always relied on our company insurance on parcels, not carrier insurance. The carriers have too many 'get out of paying' clauses and entire departments dedicated to avoiding paying. A company sending tens to hundreds of parcels daily may have some leverage over a carrier. But you as an individual, no chance.