Shooting Stars (by sarah)

Last night I watched the Geminid Meteor Shower - my great Aunt died the morning before and I feel isolated and cut off from the family that surrounded me as a child - she was the last link I had to that really - to that older generation - we all knew she was ill and in her 80's but somehow it still sliced as a knife and I cried and I wasn't sure weather I was crying for her or crying for my nan or the child that was or something else but I just remember all her jewellery and sitting around the kitchen table and darting between hers and my nana house - they were in the council houses at the base of the tower blocks and my great gran was just over the road in the old peoples home and sometimes we'd all go and see her and take her food.

This year has had death and life in it sometimes that spell in-between did not even get to birth. And I am dwelling, the sorrows piling up and threatening to drown me and an apathy is calling as I see the pain once more of those who chose to leave transferred and intensified in those who they have left behind.

So many things to worry about and I can't seem to help stem the tied of hurt and pain and death, I am still trying but the trying is getting harder.

I made mulled cider, hot apples and chocolate milks of varying temperatures and invited people round - they were already invited but I enhanced and kept it that way so as not to disappear into a ball of misery. I had canceled the plans of the previous day as a void yearned and pulled at me and the tears poured from my eyes with both intensity and numbness and there was just me in a pool of warmth that I know was my husbands arms but I did not really see him.

And so I had to make sure we still did something so we watched the stars, my little ice gems of twinkling sky that I know are hotter than fire and ring like bells and the shooting stars are rocks that I love the crystal patterns of and the ripples of cold melt that coat their surface once they have - if they ever do - reach the ground.

When I came to try and write all of this, to share with others what the night of light smudged night was like, it came as a poem.

I watched the shooting stars with my family and friends, there were a few around at in the early evening though the youngest grew bored. The meteors were glorious later on - everyone else had buggered off including my family to great Morpheus or sleep or a warm bed at least - so it was just me and bits of burning rock from space and the mortality pain hit - all of this wonderfulness often over ridden by pain and anguish and all that getting to know the world and just as life fits like a well fitting shoe no long giving blisters - whoompf you are gone to goodness knows where - maybe riding the back of those steaks of light or sitting with the sky daddy, or to be cradled by the arms of Gaia or just a nothing.

I watched the shooting stars remembering that like me they too were star dust and named them after the loved until I ran out of names and then I beheld the others as the lost ones I could not or did not want to know, held them as the sorrowful lonely deaths because though we all ultimately face death alone some of us have to face life on our own in desolation and that is a bone chill blood curdle of a thing that slices at the very humanity of us.

I watched the shooting stars and they reflected in my tears for the losses of this and all years and tears of gratitude at the wonders and spectacles and love that those same years have also brung. I watched the sky rocks blaze. And then folded strips of paper to glow in the dark as wishes, they were of course what we have decided is a star shape though it is pointy and not spherical. Tonight again I will watch the shooting stars.

Periods and Political Dreams (by sarah)

Womb of DOOM is giving me periods where I can hardly walk for sharp pain along the base of my c-section scar combined with a mix of heavy clot loss and headaches - they are not heavy heavy like in the past but to be honest the first day is full of contraction pains where I am struggling - I am hesitating to call them bad - I'm a little nauseous but am not throwing up or passing out etc... and it's only lasting like this for about a day so I suppose they are an over all improvement? But people panic if I double over sweating and I myself am not sure how much will... er... flow with each contraction like pain so this is my third proper period since the last miscarriage and I have a fever and am struggling to walk... hence I am not going into town for my business networking event and am very relieved it didn't hit me when I had a workshop or performance as it it is exhausting to try and still function and hide the pain. As I said I've had far worse periods but the pain tended to be at a stead level not whamming me and retreating so I forget about it and then whamming me again.

In other period news - I've been using a lot of pads due to irregular bleeding since Mary was born (almost 8yrs ago now) and sometimes they make me sore and I end up have to just use cloth when lightly spotting. Then whilst going through old diaries I discovered that I'd planned to make cloth ones for use at home before I had Mary but then my bleeding was so ridiculous and then I had the head injury... yada yada yada... that I forgot. Upshot of this I don't have to make my own or ask my mum too - they make them these days in multipacks - so I have bought a set and we shall see - not sure how they will handle fist fulls of black jelly but then my normal (the most absorbent ones I can get and the longest) fail with that one.

Also I am getting fever dreams for the three or say days before the period hits along with night sweats :/

Last nights fever dream - I was trying to mediate between May and Corbyn with all the politicians/MPs watching in a kind of Roman amphitheatre but it wasn't working very well so I gave them all the friendship bracelets I'd made and took them to a larp/cosplay/gaming event where I lost them amongst all the teenage uni students - then I gave all my left over bracelets to my friend Layla (probably should mention she is a Lib Dem MP) and promptly realised I was wearing no trousers and someone had stuffed my children in the back of a lorry and I had to go and rescue them and all the others and then had lots of kids I had to try and find homes for/return to their homes because there wasn't any children services or police. May insisted on shaking my mothers hand whilst she sat bemused on her mobility scooter and it all got very awkward. Really really not sure what was going on with this on :/

autocorrect changed LARP (live action role playing) to lap as in lap dancing 0.o

Last Minute Workshop! (by sarah)

Tomorrow Salaric Craft will be doing the Creative Take Over at the BlackFriers Hub in Gloucester - Wed 5th December 2018. Wednesday is their normal creative take over with workshops and co-working space and of course free biscuits!

I have been looking for spaces to run my Upcycled Christmas Workshops which are free with donation bucket and they have Kindly stepped forward asked me to host!

And host I shall - I am bringing with me ink stamps, pens, crayons for rubbings etc.... and a big roll of recycled packing paper for turning into your very own custom wrapping paper and also.... bits to make upcycled cards and name tags 🙂

If anybody else in the Gloucester area would be interested in this workshop then please ping me a message 🙂

The Good, The Bad and The Ugly (by sarah)

Yesterday we went to the allotment to begin the slow down for winter.

Preping the allotment for some fruit canes 🙂 and broad beans, finding frogs which are now safely in Mary's container/fairy garden, digging up the last few root veg that were ready - all yay!

We also have late tomatoes which are still producing green tomatoes so it is time for more chutney making!

Discovering someone has stolen two of my galvanised herb pots turfing my rosemary plant which I grew from seed when we first moved to the cotswolds >:( They left the third so I think they must have gotten interrupted. Big boo >:(

There was also wood smashed up and thrown into one of our planters and the grumpy man who is sometimes there came and stared at me and the kids for a while before moving on :/

Ending with the frog pics because they are cute - Mary has named it Slimey unsurprisingly. It is in the Fairy garden because a) cats b) streamers.

Slimey is pictured her in the empty worry trays that I use for weeding.

Last night was the only opportunity we had to take the kids to fireworks but I hadn't slept properly and then had failed to have a nap so decided not to go with Al and the kids - he say's the fireworks would have been borderline for me as there were a lot of flashing crowns and wands and shoes and I hadn't had a lot of sleep so I made the right decision in not going - I want to get through this November without a seizure as they set me back so far and it's like I've hit my head all over again so I am being extra cautious because I am so much better that I just don't want to risk it - but I felt like a bad parent not going but Al would have had to carry a fold up seat and stuff for me as well and I think it would have made it miserable for everyone if I had gone - we toasted marshmallows over candles when the girls got back and I managed to cook my first meal proper with little mess and no burning or mess ups since the head injury (this is cooking on my own rather than with Al or Jean) - so pretty pleased with that.

However...

TW: miscarriage

Having nightmares at the mo - the next week is going to be tricky but I have craft supplies and have already made a bazzilion cards and keyrings - my plan is to bulldozer through - this is the day last year where I left the house walking and excited about all the awesome stuff I had planned for November and had to be brought home by a friend as thing started to go wrong very quickly and I couldn't even walk properly and felt like I had been hit with the flu hammer - nightmares are of course all hospital based or searching for lost babies/kittens/cute things or failing to rescue them no matter how hard I try - very grateful to the NHS and very aware I wouldn't be here if they hadn't worked so hard - I ended up with a server BP crash and seizure fortunately I was already at the hospital - this one has affected me far harder than the one in the summer - but it was a pregnancy that was older and it was far more traumatic. Trouble is I get cascade so the memories of that hospital trip flash to others including the trips to A&E whilst half way through Jean's pregnancy.

Big irony about this is that I can recall peoples birthdays and I even struggle with things like Christmas but this and the ectopic are burned into me. I accidentally woke Al up crying last night which I wanted to avoid :/

I'm also getting hacked off with myself for still being so drenched in this - it doesn't help that the pelvis has just not really recovered so I have a reminder every time I walk - I basically gave birth to the placenta which was the size of a small baby.

It's eating at my core partly because I fear it was perhaps my last chance to have a baby.

My craft obsession:

Card making is a big thing for me when I am feeling too frazzled or sick to do much else. Alaric bought me supplies, including a Christmas gift box colouring in book.

I've been making cards including ones of my St Oswold's picture I did in the summer.

Last night when I couldn't sleep I remembered I had lots of split rings to make keyrings with - so I combined them with my bracelet charms.

I am making lots of lucky dip pouches to go in the treasure chest.

I have to end the post with my guardian cat - Hydrogen has been through the mill of life and still likes to sit with me and purr. Here she is being a Dragon Cat with her horde of keyrings.

Radio Waves (by alaric)

I really love learning things, and recently I've finally been removing a long-standing thorn in my side - the fact that I don't really understand radio frequency electronics and the propagation of radio waves.

I've tried to fix this a few times in the past, but the resources I'd read never seemed to quite explain the whole picture - and I couldn't see how to piece the things they explained together into one coherent understanding of the electromagnetic world; they were clearly only shedding light on little corners of a totality that still remained mysterious to me.

Well, there are still gaps in my understanding... but I've made some progress, and in the hope that I can help others struggling with the same confusions as I was, I'd like to share my way of understanding it all.

One thing that bothered me was that explanations of transmission-line behaviour seemed to flip between talking about instantaneous voltages and currents at some point in the line, sampling the analogue signal traveling down the line - or talking about an RMS average voltage or current, and thereby causing me to struggle to make sense of what they were saying. But I think I now get transmission lines to some extent (although I'm still hazy on wave guides, because I've not gotten around to looking into them yet). And I was never quite sure what the impedance of a whole transmission line really meant, regardless of its length. If I had a transmission line and put a resistor over the end of it, and hooked it up to a battery and an ammeter, I knew that the current flowing would depend on the total resistance of the line and the resistor at the end - which would depend on the length of the line, as its resistance would be in ohms per meter. So what the heck was this impedance thing about? How did impedance mismatches cause reflections?

So, here's how I think about transmission lines now. The "DC model" of hooking a battery up to one end of a line and reading the current that flows into it is, of course, perfectly true - we can set the circuit up and test it; the reason it doesn't contradict with this weird parallel world of impedances is that the DC model is a steady state model of the system. When you first connect that battery to the line, current is going to start flowing into it, crawling along at a sizeable fraction of the speed of light; but until that current has reached the end, flowed through the terminating resistor, and flowed all the way back, it can't possibly have communicated any information about the total resistance of the line and its terminating resistor... So how much current initially flows from the battery, and why? Of course, the line can be thought of as two series of tiny inductors (with resistors in series, if we assume the inductors are perfect) with tiny capacitors connecting the two conductors, due to the inherent inductance of the wire and the inherent capacitance of the gap between them; you can imagine that the current from the battery has to charge the capacitors through the inductors for the voltage/current surge to propagate down the line. But what made "impedance" really click for me was going back to the basics of Ohm's Law and seeing it as a ratio of voltage to current. At any point along that transmission line, a certain instantaneous current will be flowing - and there will be a certain instantaneous voltage between the two conductors at that point; and the voltage divided by the current is the impedance.

So, if a 12 volt voltage source is connected suddenly to a 50 ohm impedance cable, an instantaneous current of 0.24 amps (12̣̣̣̣÷50) will flow. Now, as Kirchoff's current law tells us, the currents flowing into a node must sum to zero; so with the imaginary node at any point on the transmission line connecting two halves of it, the input current must equal the output current (although some current may be lost to resistive heating or leakage, that's not relevant in this case). So what happens when there's a change in impedance at some point in the transmission line? The current must remain the same, but the impedance changes - so the voltage must change, to make Ohm's Law still hold. If my 50 ohm cable is connected to a 75 ohm cable, that 0.24 amps flows into it and changes into a voltage of 18 volts (0.24×75). Which is why high impedance transmission lines are less lossy; a transmitter putting a watt of power down such a line (with proper impedance matching) will push out a higher voltage with less current that one putting a watt of power into a low impedance line - and resistive losses in the cable are worse for higher currents.

How about the reflections when impedance changes? I'm still a little hazy on this, but I think it's something along the lines of this: imagine a point just where the impedance changes in our example of moving from a 50 ohm cable to a 75 ohm one. A current is flowing into that point, but the voltage is higher after that point than before - which is going to create a current traveling back the other way. Where I'm hazy on is how this happens at junctions where the impedance falls (is it to do with the fact that the current flows alternately backwards and forwards, so the junction is traversed by current in both directions anyway, and the phases where the current travels from low to high impedance are what create the reflections? If so, isn't that a kind of rectifying action, that will create harmonics and intermodulation? But what is the "direction" of a signal traveling along a line, anyway? If we froze the signal in time, we'd just see a sine wave of voltage and a sine wave of current along the transmission line - if we restart time, how does it "know" what direction to propagate in? Something to do with the relative phase of the voltage and current waves?) So, yeah, I've a little more to learn there.

But this model of impedance does explain a lot. I wondered why the angles of the radials of a ground-plane monopole antenna affected impedance, but now it makes sense - the end of the transmission line basically spreads out to become a dipole, or a monopole and its ground plane; the electrical field of the traveling signal has to cross a larger region of space, so it makes sense that the voltage required to do so might vary depending on the amount of space crossed. All the mysterious constants, like the fact that a dipole trimmed to 0.48 times the wavelength has an impedance of 70 ohms are really down to the electromagnetic stretchiness of space: the impedance is the voltage required to push one amp along a transmission line (a dipole antenna just being an oddly-shaped transmission line, handing the signal over to the even weirder transmission line that is free space itself), and that is a function of the permittivity and permeability of that space.

This model also explains how impedance matching transformers work. A 1:2 turn ratio transformer will transform X volts and Y amps on the "left" into 2*X volts and Y/2 amps on the "right"; as the impedance is V/I, that means it converts R ohms on the left into R*4 ohms on the right, simply through changing the voltages and currents. A 1:N turn ratio transformer makes a 1:N^2 change in impedance.

Antennas with multiple elements are confusing, but I'm not sure anybody really understands them - as far as I can tell, the design process is almost always to mock it up in a finite-element computer simulation or build a prototype and tweak the design until the desired parameters are obtained experimentally; the mutual interactions between the elements (not to mention ground, support structures, and the transmission line feeding the antenna) are just too complicated to analyse.

I really don't get why there's a near field and a far field (or that funny one in between that, I think, is just a mixture of the two). Does the antenna both far and near fields at once, and the near field is stronger but doesn't spread out far, so the far field is negligible when close to the antenna? Or does the antenna create a near fields, which "decays into" the far field as it spreads out? Nothing I've found seems to explain.

I'm not very clear on why a balanced transmission line that's shorted at one end and open at the other end has varying impedance along its length, and can be used for impedance matching, but it doesn't create reflections from the ends.

But, I can understand how to run a cable to a dipole or monopole antenna, manage the impedance transitions, and make it radiate efficiently. That's progress!