Anonymous
Spectrum analyser oscillator choice 2017-03-15 09:49:18 Post No.1145336
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Spectrum analyser oscillator choice 2017-03-15 09:49:18 Post No.1145336
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Spectrum analyser oscillator choice
Anonymous
2017-03-15 09:49:18
Post No. 1145336
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Hello,
I am currently doing a school project which is making a spectrum analyser (700MHz to 2500MHz). For this, I chose to make a double superheterodyne receiver with the first IF filter of 86.85 MHZ and the second of standard 455kHz. The first oscillator will be made with a DDS and I don't know how to make the second one as it must be very precise in frequency which is 86.395MHz (no more than +/-5kHz in the wors case). I planned to use a Colpitts oscillator with a quartz of a frequency which would be close to the 86.395MHz but I couldn't find any (I live in Europe). Would you happen to know any solutions to my problem?
My circuit is exactly the same as the one which is posted on the picture but I don't have any amplifier which is after the first IF filter.
I bet that there isn't any other way of getting rid of image frequency than using a double superheterodyne. In my case the spectrum is so large that anyway I will have to deal with it.
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>>1145336
If you use a tcxo combined with a pll you can get in the 5khz range of accuracy at that frequency.
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>>1145340
In fact I think a tcxo isn't even necessary to get into that accuracy range. But why don't you use a more easily dividable frequency? Like 70Mhz or something? Also if you don't know this link yet you'll like it: http://lea.hamradio.si/~s53mv/spectana/sa.html
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how easy is plastering ?
what are the main bullet point essentials i need to know before i go looking through shitty video tutorials ?
15 Posts / 1 Images
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>>1145277
you need two hands, preferably bigger than 2 inches
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>>1145277
Real, honest to God plastering? It's a skilled trade, not something you're going to just pick up right away and do like a pro. It's not impossible, but it'll take practice.
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>>1145277
plastering isn't complicated, but you have to work to the pace of the mud so if you're doing a big ceiling and the mud is drying fast, shit gets frantic.
you really want a second guy doing the mixing and washing-up and running around so you can concentrate on the trowel, float and feather edge.
main bullet point essentials:
if the wall isn't sound, you need to fix that first! don't plaster over growing cracks, damp patches, missing bricks, rotten lath or loose electrical wires!
ok
>mix up some mud
>slap the wet mud on the wall
>smear it flat before it goes too hard to push around
>as it stiffens you can polish the surface of the mud smooth
>throw away the extra mud mix that's gone too hard
>wash all your tools before the mud stuck to them goes rock hard
>don't let those little hard bits get into your next mix
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Can someone teach me how to read and understand what I'm looking at, or even just point me in the right direction? I don't know what even to google for this because I don't really know what it is. A blueprint? An AutoCAD rendering? I have no idea. If someone who knows this shit can explain it to me then I'd be really thankful. All I know is it's something related to a building layout.
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>>1145032
>File: universal-studios-soundstage
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looks like a reflected ceiling plan - meant to show ceiling features (beams, lighting, clearances). You usually have a variety of plans in a design package - flloorplan, reflected ceiling plan, floor finish possibly, construction plan, elevations, details etc etc
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>>1145032
You are looking at a floor plan of Universal Studios Florida Stage 19.
It is showing fire lane which is the area that must stay clear for fire escape. It is showing the Desisti flying lighting grid which is the fixtures for lighting on the ceiling.
The left image is an elevation of the interior space, drawn sideways to correspond to the plan, it is showing the dimensions of the trolley beams for trolley to run along.
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Got a new toy that runs off 18v AC using a power adapter like pic related.
>want to make it battery powered
>two 9v batteries make 18v in parallel, but it's DC
>how to make a DC battery to AC 18v power supply?
I can't even begin to guess where to look on how to build one myself, much less be a buyfag and buy one
>yes its for audio equipment
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>>1144990
>>yes its for audio equipment
More specifics please. Schematic diagram of equipment would be ideal.
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>>1144994
No diagram, but this is what wants the power.
>18v AC input
>fucking bullshit
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>>1144999
Open it up and replace the power circuit with some 9 volts and a boost converter.
or get a decent audio interface that actually has phantom power
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I need to do some welding in 0.8mm (1/32) steel sheets. All I have at home is an oldish stick unit that I can't for the life of me drop below ~50A. Also, at the location I have no space to put any kind of plate behind. Is there any combination that can work with this, or I'm better off just trying to source a mig unit for steel this thin?
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>>1144969
why not revet
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>>1144970
I don't really think riveting a car's body is a good idea.
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>>1144969
what kind of weld are you trying to do nigger? if it's a butt joint you can forget it at 50A, i would say fillet or plug weld but you if you can't get some aluminum behind there that's not going to work out either.
if the seem don't have to be sealed or it can be sealed later with something else then do a 1/2" overlap and have a person either side with brass electrodes and spot weld it with AC. no other way besides foot pedal TIG afaik.
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I want to make a functional piece of Japanese paper armor and google isn't helping much.
I want to make a solid chest piece, the materials are easy with it just being paper, fabric, glue, and lacquer but i cant find anything on the process.
I've found two videos of people trying it but they've both come out looking like absolute shit, can anyone help me figure out how to do it properly?
The finished piece would be shaped like in this image but not plated since that is iron or steel.
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>>1144895
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>>1144843
These are the only two videos i've found, so you can understand what i'm wanting to make
They both turned out like shit.
https://youtu.be/C76cJpFEskY
https://www.youtube.com/watch?v=ze0yKhoWV4E
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Hi /diy/. I finished my light gun controlled drum sequencer project. What do you think?
https://www.youtube.com/watch?v=BhoqS5sP0P4
It's for this contest:
https://www.moogmusic.com/news/6th-annual-moog-circuit-bending-challenge
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That's fucking awesome
10/10
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>>1144808
That's more than slightly dope my dude
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Needs more /pol/ tapes for lulz
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Hey guys I'm making a copper pipe drop down hopefully with a kicktail. I'm using 1/2 inch and will solder it together. I was thinking of putting an epoxy or resin inside it to make it stronger and coating the outside with some sort of clear resin. Its cost me 200 and 5 days of work so far. I'm also considering welding it. Made a moose antler board a weed board and a pykrete board.
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What
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what a waste of good copper piping
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>>1144726
>Its cost me 200 and 5 days of work so far.
not sure if srs
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Any brands that have screwdrivers with that old style, hard plastic? handles instead of rubberized one used today?
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>>1144696
Craftsman screw drivers still use the hard plastic.
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>>1144698
Thanks, I will look into that.
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Pratt Read, I got a set from a local TrueValue.
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i am currently processing 5.25 litres of shelf stable cooked organic chickpeas for 0.03/100ml less than you can buy cancerous, bad tasting corporate walmart ones
$3.75 - dry chickpeas
$1.82 - canning rings
$0.98 electricity
$0.02 - water
$0.13/100ml
what are some other ways to save money and eat more healthy, non corporate food?
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>>1144620
First of all, b8 thread
Secondly, try /ck/
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>>1144624
it's not bait. and i hate /ck/
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Where'd you get the chickpeas from
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Can exposed plywood furniture actually look good, or is it just a meme perpetuated by pinterest moms/interior design magazines/Adobe Lightroom professionals?
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I think it looks ok, but I'm a bit of a minimalist.
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yeah it's pretty much only acceptable in certain modern/minimalist aesthetics. Otherwise snooty people recognize that it's most directly building material, not choice stock
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>>1144313
better ply than OSB. Everywhere.
Anonymous
Which 3d printer to buy? Also general 3d printing thread 2017-03-13 02:34:35 Post No.1143761
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Which 3d printer to buy? Also general 3d printing thread 2017-03-13 02:34:35 Post No.1143761
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Which 3d printer to buy? Also general 3d printing thread
Anonymous
2017-03-13 02:34:35
Post No. 1143761
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Fairly new to 3d printing, but I know I'm going to be using whichever I buy quite a bit throughout my industrial design education. Both are decently similar in cost and have great feedback but there are so many things to consider that I can't decide.
I was a Tiko backer so obviously I'm frustrated, amplified because I just recieved the M3D micro a few days ago (pissed at how tiny the print bed is)
The monoprice is built like a tank, and besides all the acrylic so is the tarantula. both are very customizable, but I've heard calibrating the monoprice is frustrating. The tarantula's print bed is much larger, (especially with the upgraded 200x280 bed) but it's a DIY kit which might be a downside considering I've never built a 3d printer before. soo many things to consider.
What do you think would be the better way to go?
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This would be more suitable for the /3dpg/ thread, whenever the new one pops up. Which monoprice are you refering to? Monoprice just sell rebadged stuff from other manufacturers.
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Go for monoprice since you were stupid enough to fall for tiko and M3D.
If you were retarded enough not to see the red flags in those machines, you putting a kit together that is known to be a fire hazard straight out of the box isn't a good idea
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>>1144176
No need for the insults, guy. But i agree, it may be best if OP gets a prebuilt machine. The various printrbot models are "just werks" type of machines, but they cost more also.
Anonymous
How I fixed my leaking in-ground pool 2017-03-13 12:04:41 Post No.1143708
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How I fixed my leaking in-ground pool 2017-03-13 12:04:41 Post No.1143708
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How I fixed my leaking in-ground pool
Anonymous
2017-03-13 12:04:41
Post No. 1143708
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When I got there the thing hadn’t been run for a year. Four thousand gallon pool – 800 in the hot tub and 3k+ in the cocktail. The theory was that a root had broken one of the jet plumbing pipes (pvc) and was losing at least two hundred gallons a day. Water level would go below the jets and slow to a crawl (evaporation).
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Dug out under the slab and found good pipe but did run into a gnarly root from I was able to hack out, just because ~ refilled hole.
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Next guess was this big can light at the end of the pool. Got myself a tube of 5200 boating bond and sealed that sucker up tight – this ended up being the leak.
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After a good acid wash I repainted it blue – two thick coats
Anonymous
Restoring a coffee grinder. 2017-03-12 09:16:39 Post No.1143607
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Restoring a coffee grinder. 2017-03-12 09:16:39 Post No.1143607
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Restoring a coffee grinder.
Anonymous
2017-03-12 09:16:39
Post No. 1143607
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Hi /diy/ today I started restoring a coffee grinder. It was mounted on a piece of wood, which I removed before I took this shot. It's supposed to hang on the wall. While I was renovating my kitchen it was outside and the coffee inside spoiled so I wanted to take it apart and get it completely clean and usable again.
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>>1143607
Why are you restoring it?
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This is the grinder disassembled in its parts. Because it was outside it got wet, even the inside so there is rust to remove.
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>>1143609
It got wet, so I disassembled it, to clean it from the inside.
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Recently got my own house so I'm tooling up. No more stealing pop's tools.
Saw this Metabo set and thought, 'thats nice for home DIY'. (PowerMaxx BS Quick Pro + PowerMaxx SSD) Costs £200 (~$240 USD).
What drill features are useful or a waste of money?
For me a DIY drill needs some speed control and a clutch to avoid murdering screws.
DESU not sure why I need an impact driver but they seem to excite people.
Its the small battery version so it should be lighter and easier for amateur DIY, I don't see the need for the giant batteries and power.
I might get a separate corded hammer drill for concrete but that's a rare need.
Other basic stuff:
> Spirit level
> Some spanners
> A screwdriver (got a ratcheting Bahco 808050 )
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>>1143514
Don't get me wrong, Metabo is a fine brand. But why one should fork out ₤200 when I can get pic related for €175 (as an example) is beyond me.
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>>1143544
Hmm that's a nice suggestion, but I like having 2 drills, I make stuff out of wood, lots of drilling and screwing, Its nice to have one for each.
I suppose that still doesn't justify buying the impact driver though. Could probably get something even cheaper for just screwing.
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>>1143514
>240 USD
do you britbongs not have yardsales/swapmeets/etc?
never buy new the first time you get a tool. 240 USD would buy me damn near a whole wood shop.