Archive for the ‘Microwave’ Category

Microwave project managing – week 6

Other News

The fan in my lap­top died this week. It has been strug­gling and groan­ing nois­i­ly along for a while now, occa­sion­al­ly the boot has even failed due to a fan error but a sec­ond shot always got through. While I had the sys­tem switched off I thought it would be a good idea to blow the dust out and give it a bit of love. It still groans along but now the fan error is con­sis­tent. :( I have ordered a replace­ment fan which should arrive next week. In the last six months I have had to swap the bat­tery, hard dri­ve and fan. Maybe my Leno­vo is reach­ing the end of its lifes­pan, 2008 was a while ago and appar­ent­ly it doesn’t even run WOW.

Other Other News

In bet­ter oth­er news, a friend point­ed out that a recent XKCD what if? post is on the top­ic of microwaves. Because it seems microwaves are awe­some.

Screen

I have con­tact­ed sev­er­al sup­pli­ers of the Banana Pi and a screen sup­pli­er to get price esti­mates. The screen sup­pli­er may be able to fit the touch­screen, which is a bonus, oth­er­wise I have some touch­screen sup­pli­ers select­ed to approach.

The ini­tial Banana Pi pric­ing is $29 USD in quan­ti­ties of 500, $34 for sam­ples. I am look­ing at a sev­en inch IPS screen which I expect to be rough­ly $15 and anoth­er few bucks for the capac­i­tive touch­screen. So a total bill of rough­ly $50 USD with no elec­tron­ic design required, which makes me very hap­py.

An inter­est­ing side note is that both the Rasp­ber­ry Pi and Banana Pi fea­ture a rib­bon con­nec­tion for the screen which fol­lows a stan­dard by MIPI (not an acronym) called the Dis­play Ser­i­al Inter­face (DSI). This is a fair­ly stan­dard inter­face used by the mobile phone indus­try which makes it very nice to pick up screens for. The Rasp­ber­ry Pi hard­ware has always fea­tured this con­nec­tor how­ev­er the dri­vers to use it weren’t ini­tial­ly pro­vid­ed by Broad­com, so most of the screen acces­sories use the HDMI port. When the Rasp­ber­ry Pi foun­da­tion released their screen it used the DSI inter­face and was paired with a dri­ver release. How­ev­er this dri­ver still only uses some of the bus (half the LVDS chan­nels by some reports) so you can’t use stan­dard screens with it. The All­win­ner chip used by the Banana Pi has full sup­port. The only remain­ing annoy­ance is that the DSI bus sup­ports an I2C chan­nel for the touch­screen but all the screen man­u­fac­tur­ers seem to use a sep­a­rate touch­screen cable, I may even have to do some design work.

Schedule

So, it prob­a­bly isn’t a shock after I com­plete­ly blew a week or two that I am rapid­ly approach­ing the end of the eight week eval­u­a­tion peri­od and there is an awful lot not yet done. Essen­tial­ly all of the out­stand­ing work is doing pre­lim­i­nary work in the tech­ni­cal inno­va­tions I hoped to achieve.

Break­ing it down into tasks we have sub­head­ings.

Thermal Camera

The ther­mal cam­era is a key body of work that I have let slide.

I iden­ti­fied two poten­tial cam­era sys­tems to eval­u­ate, the Seek Ther­mal which I have got­ten a sam­ple of and the Pana­son­ic Grid-Eye 8x8 which I man­aged to get Pana­son­ic to agree pro­vid­ing sam­ples of. The plan was to com­pare, decide, poten­tial­ly make an approach to Seek Ther­mal etc.

The plan went awry when I met Braemac a local dis­trib­u­tor of elec­tron­ic goods includ­ing Panasonic’s. There are two com­pa­nies in Aus­tralia that do this sort of dis­tri­b­u­tion, Braemac and Avnet. I have inter­act­ed with Avnet a fair bit, they dis­trib­ute Xil­inx chips so at my last employ­er I was on first name terms with their Xil­inx sales/support guy. Pana­son­ic actu­al­ly uses both com­pa­nies, I chose Braemac in this instance as they are the small­er of the two and I thought it would be good to build a rela­tion­ship into the oth­er elec­tron­ics dis­trib­u­tor. My only pri­or expe­ri­ence with Braemac was also at my last employ­er, we were try­ing to pur­chase some U-Blox GPS mod­ules. We ordered them well in advance but Braemac man­aged to slip the deliv­ery three times, as we were get­ting into dam­ages ter­ri­to­ry with our cus­tomer I reached out to some­one senior I knew in U-Blox and we man­aged to get some emer­gency com­po­nents from Sin­ga­pore. It seems like this neg­a­tive expe­ri­ence wasn’t a one off.

I had done all the work, it real­ly should have been rather sim­ple for Braemac. I had approached Pana­son­ic, they had agreed to pro­vide the sam­ples, every­thing was arranged except for me giv­ing over mon­ey. Pana­son­ic sent the price to Braemac, Braemac’s job was to put their head­er on it, take my mon­ey, remove their cut and pass the rest back to Pana­son­ic. We are only talk­ing sam­ples at this stage so they prob­a­bly aren’t mak­ing a prof­it but it isn’t like it is a great deal of work.

Braemac man­aged to not respond for eleven days, and even then sev­er­al days after I con­tact­ed Pana­son­ic to give them a shove, their feed­back to Pana­son­ic was sim­i­lar­ly absent.

The Pana­son­ic rep offered a sam­ple quan­ti­ty of ten. Ten is a fair­ly high num­ber for sam­ples, accept­able but gen­er­al­ly for a com­plex part you get 3–5 sam­ples. The Braemac email list­ed a min­i­mum sam­ple quan­ti­ty of 100. I have nev­er before heard of a man­u­fac­tur­er demand­ing the pur­chase of 100 units as a sam­ple. Even sam­ples of triv­ial parts like capac­i­tors aren’t done in lots of 100. Why would you eval­u­ate some­thing 100 times before mak­ing a deci­sion?

When ques­tioned about the sam­ple quan­ti­ty Braemac haven’t respond­ed, it has been two weeks so far.

I need to get on top of this ASAP. Even once ordered it will prob­a­bly take sev­er­al weeks to get the sam­ples and a week to eval­u­ate them. There is no way I am going to close this out by the end of the month.

The plan going for­ward is to call the Braemac rep on Tues­day. If I can’t get it resolved on the Tues­day I will aggres­sive­ly pur­sue sam­ples through Avnet. I can’t see resolv­ing the cam­era sys­tem by my deci­sion dead­line, I think the best I can hope for is to get as much done as I can and deal with it at the time. Mak­ing a via­bil­i­ty call with this ele­ment so uncer­tain is dif­fi­cult, I may have to put a sec­ondary eval­u­a­tion date in.

Inverter

I would like to include an invert­er sys­tem in my microwave, it isn’t crit­i­cal but cer­tain­ly a nice to have. I con­clud­ed a while ago that the only viable way for­ward was to buy the sys­tem from Pana­son­ic, parts, patent licence etc. as a com­plete kit. This seems to be how oth­er man­u­fac­tur­ers such as Sharp have approached it.

My plan was to use the cam­eras to build a rela­tion­ship with Pana­son­ic and then broach the ques­tion of the invert­er tech­nol­o­gy. I think I have enough of this so far, I’ll raise the invert­er tech when I talk to Pana­son­ic in the process of resolv­ing the cam­era sam­ple mess.

Scales

The scales tech­nol­o­gy is rel­a­tive­ly sim­ple. I am con­fi­dent that I can han­dle the elec­tron­ics side and will be able to at least esti­mate the cost by the end of the month. It will prob­a­bly involve a cus­tom PCB which is increased risk but it should be a sim­ple one.

The out­stand­ing ele­ment here is that I am prob­a­bly going to need to cre­ate a cus­tom plate for the scales. There are a few options with dif­fer­ent cost/design trade­offs but I need to be more knowl­edge­able about the costs involved in plas­tic fab­ri­ca­tion to pro­ceed.

When deal­ing with the met­al fab­ri­ca­tors some plas­tic com­pa­nies were men­tioned. I need to line up a vis­it next week and get an under­stand­ing of the dif­fer­ent tech­niques with their tool­ing and unit costs.

No turntable

The lack of a turntable in the sys­tem is basi­cal­ly a require­ment to get the scales work­ing.

Again the tech­nol­o­gy, a basic under­stand­ing of it, is sim­ple enough that even I have grasped it.

I just haven’t found any­one who sells them pre­made. Pana­son­ic prob­a­bly anoth­er option, I’m giv­ing them all my mon­ey any­way… I could also grab one and get a met­al ben­der to clone it but the part needs to be pre­cise­ly made. Design­ing my own would prob­a­bly require RF mea­sure­ments to do it prop­er­ly which is com­plex and expen­sive, not to men­tion how ter­ri­fy­ing RF design is.

Screen

The screen is actu­al­ly look­ing fair­ly good. I haven’t received the sam­ples to try out but that is fair­ly low risk and should hap­pen before the end of the month. I have a solu­tion and enough infor­ma­tion to esti­mate the cost solu­tion, which is all I real­ly need at this point.

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Microwave project managing – week 5

Update

So I real­ly didn’t do much this week. I have always suf­fered from occa­sion­al days where my pro­duc­tiv­i­ty drops off and I achieve vir­tu­al­ly noth­ing. I found that work­ing solo this was much hard­er to arrest and con­trol.

In the spir­it of full dis­clo­sure it was more like two weeks. With a fair­ly sharp decline in the sec­ond half of week 4, the entire loss of week 5 and the first half of week 6. I had over­run set aside in the sched­ule, I had hoped that if it was need­ed it would be due to exter­nal fac­tors… but it means the impact isn’t as bad as it could have been.


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Grants

Rather than leave this entry com­plete­ly depress­ing­ly emp­ty I’ll pad it out with an infor­ma­tive rant on grants.

Pri­or to my move to the Gee­long region every time I heard the city men­tioned in the news it seemed to be attached to anoth­er bun­dle of mon­ey. Espe­cial­ly around the Fed­er­al elec­tion it seemed like politi­cians were deter­mined to drown Gee­long in largess.

So when I hatched this deranged plan and moved to the region look­ing into these buck­ets of cash was always on my todo list. I’m start­ing a busi­ness, it’s new and inno­v­a­tive, in the right area and I may even have to employ peo­ple one day. It is some­thing a num­ber of peo­ple I have talked to have also men­tioned.

I will fore­shad­ow slight­ly by say­ing that every­body who raised it was from out of the region. None of the local accoun­tants I talked to raised it, the one I brought it up with is well con­nect­ed with the region­al com­mu­ni­ty and knew noth­ing about them.

Grants are award­ed by the Fed­er­al and State Gov­ern­ment depart­ments, coun­cils as well as pri­vate busi­ness­es. I sus­pect in the past being aware of a grant was a big prob­lem so the gov­ern­ment has made that part of the process much eas­i­er, with their Grant Find­er web­site.

Using the Grant Find­er you select your region by state, indus­try and a few oth­er ele­ments. It then pro­vides a list of rel­e­vant grants to look up the details of. My list was rough­ly 220 items long. I man­aged to cull this down to about ten worth look­ing in to. I will men­tion though that the City of Mel­bourne has an impres­sive col­lec­tion of grants if you a start­ing a small busi­ness in the Mel­bourne CBD.

GRIIF

The big dad­dy of grant funds is the Gee­long Region Inno­va­tion & Invest­ment Fund (GRIIF), prob­a­bly bet­ter known as the Ford fund. Mon­ey was tipped in by the Fed­er­al Gov­ern­ment, the Vic­to­ri­an Gov­ern­ment, Ford and lat­er Alcoa. Rough­ly half the mon­ey is for North­ern Mel­bourne where the Ford sup­pli­ers and trick­le down employ­ment is actu­al­ly locat­ed. $29.5M is allo­cat­ed for Gee­long.

So far $18M has been spent in two fund­ing rounds. Mon­ey is pro­vid­ed on the basis of cre­at­ing per­ma­nent jobs, all funds must be matched by the receiv­ing com­pa­ny. The grants must be at least $50k but in prac­tice most are well over $1M, the small­est award­ed is $230k. This cor­re­sponds to rough­ly $30k per job. From the grant sum­maries it seems like the grants are bring­ing for­ward planned expan­sion and invest­ment, not nec­es­sar­i­ly bad but use­ful to note in eval­u­at­ing the scheme.

What I found inter­est­ing is that the last round closed on the 29th of May 2014. There has been no announce­ment of a third round, when I inquired as to when a third round was like­ly to occur I was told “at this stage no future rounds or poten­tial dates have been announced.”

All mon­ey from the grant must be spent by the end of the 2015/2016 finan­cial year, this is an impor­tant ele­ment of the fund because it cor­re­sponds to the time­line of the Ford job loss­es. Assum­ing you want a grant to expand your com­pa­ny with a new man­u­fac­tur­ing facil­i­ty I see a crude time­line of:
* 2 months to pre­pare the grant
* 1 month to eval­u­ate the grants
* 1 month to plan the details of the expan­sion
* 6 months to buy the equip­ment, prob­a­bly cus­tom built and sea freight­ed
* 1 month to install and com­mis­sion

With this very ambi­tious time­line you are look­ing at 11 months to fin­ish the grant based works and get the fund­ing. Giv­en that the mon­ey must be spent in the next 15 months it seems like they are run­ning low on time. I know account­ing games can be played to bring the spend­ing for­ward but I assume the gov­ern­ment wouldn’t run the pro­gram plan­ning for this.

The cyn­ic in me sus­pects that the gov­ern­ment could not pro­vide any updates until too late, then qui­et­ly close it. I don’t know the details of how the remain­ing mon­ey would be divid­ed and returned but I believe all of the par­ties would be hap­py to pock­et the funds.

GAF

The Gee­long Advance­ment Fund (GAF) is a Vic­to­ri­an Gov­ern­ment ini­tia­tive run out of the Region­al Devel­op­ment Vic­to­ria depart­ment. GAF has $11M to “dri­ve jobs growth, increase skills and inno­va­tion and deliv­er eco­nom­ic and com­mu­ni­ty infra­struc­ture in Gee­long.”.

So far two rounds of fund­ing have been run, the most recent closed on the 30th of May 2014. The first round spent $3.65M on two projects, I can’t find details on the sec­ond round actu­al­ly being award­ed. It cer­tain­ly seems as if the fund has not been exhaust­ed but no fur­ther fund­ing rounds have been announced.

GGIF

The con­sis­tent­ly named Greater Gee­long Indus­try Fund (GGIF) is anoth­er Vic­to­ri­an Gov­ern­ment ini­tia­tive. Often lumped in with the GAF, togeth­er they are called the Gee­long Devel­op­ment Fund.

One round of fund­ing has been run and award­ed, there are ref­er­ences to IXL get­ting $180k for exam­ple. The fund seems to have dis­ap­peared though, links to it are dead, there are just lots of announce­ments on its cre­ation. The Depart­ment of State Devel­op­ment, Busi­ness and Inno­va­tion (DSDBI) now the Depart­ment of Eco­nom­ic Devel­op­ment, Jobs, Trans­port and Resources (DEDJTR?), which admin­is­ters the fund only men­tion it in old finan­cial reports.

The Depart­ment Annu­al Report (page 173) lists grant recip­i­ents and shows IXL get­ting $60k, not the $180k announced in the bud­get speech. There are six recip­i­ents list­ed for a total of $695k.

I don’t know the details of gov­ern­ment grant award­ing but it looks like the gov­ern­ment announced a $4M fund, award­ed $700k with lots of nice press releas­es all along the way and have since pock­et­ed the remain­ing $3.3M with­out any­one say­ing boo.

R&D Tax Concession

The R&D tax con­ces­sion is list­ed on the grant find­er, it isn’t a grant but worth men­tion­ing any­way.

This tax deduc­tion has been around for a while and was sig­nif­i­cant­ly reworked in 2011. The leg­is­la­tion is actu­al­ly one of the bet­ter ref­er­ences, the AusIn­dus­try web design­ers sim­ply point at the leg­is­la­tion (with­out links) when­ev­er you look for details such as who is eli­gi­ble. The ATO web­site also has good infor­ma­tion.

To sum­marise (my sim­pli­fied under­stand­ing):
* You must be a com­pa­ny doing R&D work
* You must pre-reg­is­ter for the tax con­ces­sion
* You receive a tax deduc­tion of 45% of your R&D expen­di­ture
* You must have deduc­tions of at least $20k on R&D (at least $45k expen­di­ture)

The tax con­ces­sion seems to be designed for estab­lished com­pa­nies not ear­ly phase star­tups such as myself. With­out pay­ing a salary I prob­a­bly won’t reach $45k, I am cer­tain­ly not plan­ning to spend that much. My expen­di­ture is also going to be split across two finan­cial years.

As a tax deduc­tion it is also far more use­ful for busi­ness­es that make a prof­it, which I don’t have, yet.

Optus-Innov8 Seed

This Optus/SingTel fund­ed “grant” looks like stan­dard VC seed fund­ing (mon­ey for equi­ty) that they have some­how got­ten list­ed on grant web­sites. It is the kind of decep­tive amoral manoeu­vre that VCs spe­cialise in, I am sur­prised more haven’t list­ed them­selves.

Industries for Today and Tomorrow

Indus­tries for Today and Tomor­row is a Vic­to­ri­an Gov­ern­ment pro­gram run out of the Region­al Devel­op­ment Vic­to­ria office. It is designed to assist medi­um to large busi­ness­es grow and increase employ­ment.

Technology Development Voucher

The Tech­nol­o­gy Devel­op­ment Vouch­er is a small grant up to $50k for small to medi­um sized tech­nol­o­gy based busi­ness­es. It is designed for dis­crete work with a sup­pli­er such as a design firm. I was hop­ing to use it to help fund the required prod­uct cer­ti­fi­ca­tions. How­ev­er the pro­gram was sus­pend­ed after the recent Vic­to­ri­an change of gov­ern­ment and there is no indi­ca­tion of if it will resume or be replaced.

EIP

The Entre­pre­neurs’ Infra­struc­ture Pro­gramme is a sub­stan­tial Fed­er­al busi­ness assis­tance pro­gram intro­duced in 2014. It replaces eight pre­vi­ous indus­try par­tic­i­pa­tion pro­grams and is designed to be a one stop shop for busi­ness sup­port and growth. A pri­vate grant con­sult­ing group pro­vides a sol­id sum­ma­ry.

The EIP has three branch­es which seem to oper­ate inde­pen­dent­ly.
* Busi­ness Man­age­ment — Breaks down into four offer­ings, par­tial­ly fund­ed con­sul­tant run eval­u­a­tions which can then lead to assis­tance with sup­ply chain, growth ser­vices or growth grants.
* Research Con­nec­tions — Link­ing busi­ness­es with uni­ver­si­ties and CRCs with fund­ing for the col­lab­o­ra­tion.
* Accel­er­at­ing Com­mer­cial­i­sa­tion — Assist­ing and fund­ing busi­ness­es to com­mer­cialise their con­cept.

Of the three the branch I am inter­est­ed in is Accel­er­at­ing Com­mer­cial­i­sa­tion. This has sev­er­al offer­ings, the port­fo­lio, com­mer­cial­i­sa­tion advis­ers, the expert net­work and grant fund­ing.

The port­fo­lio is a list of busi­ness­es who have applied, 554 so far. Not much more to it but we can run up some quick inter­est­ing stats, I have includ­ed some tables at the end of this sec­tion. In par­tic­u­lar the num­ber of reg­is­tered busi­ness­es rel­a­tive to pop­u­la­tion shows some sur­pris­ing growth areas.

The Com­mer­cial­i­sa­tion Advis­ers are a small group of indi­vid­u­als with pri­or senior expe­ri­ence in grow­ing com­pa­nies, most are either prac­tis­ing con­sul­tants or VCs. All port­fo­lio mem­bers are assigned an advi­sor to assist them with high lev­el advice, they also assist with the appli­ca­tion process. There is also an RFT process which hasn’t yet been com­plet­ed for com­mer­cial­i­sa­tion advis­ers, it isn’t clear how this relates to the exist­ing group.

The Expert Net­work is a larg­er group of expe­ri­enced advi­sors, either domain experts or indi­vid­u­als with expe­ri­ence grow­ing com­pa­nies. The list of experts is con­fi­den­tial, the com­mer­cial­i­sa­tion advis­er arranges the link between the par­tic­i­pant and the expert. Inter­est­ing­ly experts aren’t paid, which sug­gests that the com­mer­cial­i­sa­tion advis­er prob­a­bly is.

In addi­tion to join­ing the port­fo­lio an appli­cant can apply for grant fund­ing. This has a stricter assess­ment process and lim­i­ta­tions on what the grant mon­ey can be used for. All grant fund­ing must be matched.

I am con­sid­er­ing apply­ing to join the port­fo­lio, I don’t think apply­ing for fund­ing is like­ly to be suc­cess­ful or worth­while at this point. Assis­tance in nav­i­gat­ing the busi­ness world would be rather use­ful though.

Tech­nol­o­gy  
Man­u­fac­tur­ing, Engi­neer­ing & Design 228
Soft­ware & Web Design 185
Com­put­er Sys­tems & Hard­ware 72
Biotech­nol­o­gy 69
Mar­ket  
Health & Med­ical 122
Busi­ness & Com­mu­ni­ca­tions 93
Agri­cul­ture & Food 78
Ener­gy, Min­ing & Resources 69
Infra­struc­ture & Build­ing 54
Defence, Secu­ri­ty & Safe­ty 40
Enter­tain­ment, Tourism & Sport 31
Auto­mo­tive, Avi­a­tion, Marine & TCF 24
Edu­ca­tion & Train­ing 21
OEM 20
Tex­tiles, Cloth­ing & Footwear 2
Region Count Pop­u­la­tion (k) Count per 100k
QLD 150 4676 3.2
VIC 133 5769 2.3
NSW 131 7439 1.8
WA 68 2526 2.7
SA 38 1675 2.3
ACT 17 383 4.4
TAS 14 513 2.7
NT 3 242 1.2
Surf Coast 3 26 11.5
Greater Gee­long 1 222 0.5

Microwave project managing – week 4

Camera Investigation

Some minor updates on the cam­era inves­ti­ga­tion front. The Seek Ther­mal cam­era has arrived and I have had a brief play with it. It is nice, my only crit­i­cism is that the res­o­lu­tion sits in an uncom­fort­able spot. The res­o­lu­tion is far high­er than pre­vi­ous ther­mal cam­eras with the very big blocks of data, it looks much more like a nor­mal cam­era. Which is a bit of a fail­ing, because the res­o­lu­tion is very low and bad for a nor­mal cam­era.

I haven’t been able to start to work with it though. As it is designed to plug in to a phone direct­ly the USB port is the wrong way round (male). I have ordered a USB cable which should fix this for me but it hasn’t arrived yet, expect­ing it on Mon­day.

The Pana­son­ic Grid-Eye has also been delayed. The Pana­son­ic staff mem­ber set me up with Braemac to arrange the details of the pur­chase. Unfor­tu­nate­ly a full week has passed and Braemac hasn’t both­ered to send me an email. If there isn’t any move­ment soon I’ll get them to line up Avnet instead.

Screen Investigation

Find­ing a screen to go with my Banana Pi is prov­ing to be a bit messy, par­tic­u­lar­ly a touch screen. It is look­ing like I will have to bond a screen, touch screen and pro­tec­tive lay­er. Very doable but a bit more work. I also have to decide on a screen size, the stan­dard ratios don’t gel well with the con­trol pan­el strip.

Scales

I have been look­ing in to elec­tric scales. They are essen­tial­ly a strain gauge, a thin wire that is glued to the top of a met­al block. As the block moves the wire is stretched and its resis­tance changes. The change is minor but with the wiring loop­ing a few times and a bit of ampli­fi­ca­tion… you have a set of scales.

The down side is that you have to have a met­al block that moves up and down, which is bulky. To com­pen­sate for tem­per­a­ture and keep the accu­ra­cy up the stan­dard load cell is an alu­mini­um block 5cm thick with a hole machined out of the mid­dle to give it some flex. There are spe­cial thin designs, as used in nor­mal kitchen scales, with reduced accu­ra­cy and lifes­pan.

The biggest issue though is I need to get the weight con­cen­trat­ed on a spe­cif­ic point of the load cell. I am assum­ing putting the load cell in the microwave field wouldn’t work, so I have to trans­fer the load through the base of the microwave using small holes, then con­cen­trate it to a point. Anoth­er option is to have four sen­sors and bring the load down on four points. Either way I am prob­a­bly look­ing at a cus­tom piece of plas­tic to dis­trib­ute the weight. Cus­tom plas­tic = set­up costs = unhap­pi­ness (and more research).

No Turntable

Anoth­er fea­ture I have been look­ing at is incor­po­rat­ing a mode stir­rer which allows the turntable to be dis­posed of. A microwave forms stand­ing waves in the cham­ber, these pro­duce hot and cold spots in the food. The turntable is a real­ly nice cheap trick to work around this prob­lem, by rotat­ing the food it hope­ful­ly moves through a num­ber of hot and cold spots and rough­ly equals itself out. The mode stir­rer is anoth­er approach, basi­cal­ly you put a fan in front of the microwave beam break­ing it up and spray­ing it around the cav­i­ty. This dis­rup­tion of the beam avoids the stand­ing wave, essen­tial­ly you get lots of dif­fer­ent short lived wave pat­terns, and you shouldn’t get hold and cold spots. In prac­tice the dis­tri­b­u­tion is more even but it isn’t con­clu­sive if it is bet­ter or worse than a turntable. The tech­nique has been around for a long time and seems to have come in and out of favour. The cur­rent mode stir­rer designs mar­ket them­selves as allow­ing a big­ger usable space in the microwave.

I am inter­est­ed in using the mode stir­rer because it makes oth­er ele­ments of my life a bit eas­i­er. Notably the cam­era would work a lot bet­ter if the food you were look­ing at didn’t keep mov­ing. I could com­pen­sate for the move­ment in soft­ware, but avoid­ing the prob­lem seems eas­i­er. I also think the scales would be much hard­er to achieve with a turntable.

Unfor­tu­nate­ly Aliba­ba (where I have sourced almost all my oth­er parts) has let me down and nobody seems to sell them. The mode stir­rer is a thin met­al com­po­nent which would be fair­ly sim­ple to make but must be done very pre­cise­ly. It is also a bit of fid­dly RF design and as I have sworn off doing dark mag­ic for lent it isn’t some­thing I real­ly want to tack­le myself. There are clear­ly peo­ple mak­ing them, I just might have to work a bit to find them.

As an inter­est­ing side note the cur­rent Pana­son­ic designs with mode stir­rers have cho­sen to place the stir­rer in the bot­tom of the unit rather than the top, the his­tor­i­cal­ly stan­dard loca­tion. I’m not sure if this was moti­vat­ed by improved per­for­mance or cost, it does make the base feel odd­ly fat. Not some­thing I am look­ing to fol­low suit in either way, I am cur­rent­ly pon­der­ing putting it in the side.

Other work

I also spent a con­sid­er­able peri­od of time this week learn­ing about com­pa­nies, talk­ing to accoun­tants and read­ing excit­ing gov­ern­ment web­sites. Try­ing to fig­ure out if I start a com­pa­ny now, play on as a sole trad­er and start a com­pa­ny lat­er or go with a com­pa­ny & trust struc­ture. Cur­rent­ly lean­ing towards delay­ing the com­pa­ny found­ing but there are lots of lit­tle pros and cons to weigh up.

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