Cost to build Scotty's spectrum analyzer ?

Thread Starter

DarthVolta

Joined Jan 27, 2015
389
https://scottyspectrumanalyzer.us/
https://www.qsl.net/n9zia/scotty/index.html
https://hackaday.com/2014/05/14/a-modular-1ghz-spectrum-analyzer/

I can't find a parts list or full schematic yet, there's a bunch of pages on this thing, where's the parts list ??

About what would it cost to order the parts from anywhere like mouser/digikey, and to order the PCBs from an average cost place, and get the BNC connectors/shielding/etc.

Around what price are we talking ? It would be like a super super fun kit to try and make right. But I don't have metal working tools or a even a vice.
 
Hints for the metalworking:

VSR drill
Jewlers files
DeWalt pilot point drill bits (they make round holes. Look at the tip. https://www.mscdirect.com/product/details/03801636
The set is particularly nice.
Nibbler tool: https://www.parts-express.com/nickel-plated-nibbling-tool--360-022

Optional: Dremel or Proxxon moto-tool.

You can go screw terminal to DB25.
Convert to USB
Possible chassis mt connector: https://www.l-com.com/usb-usb-type-a-coupler-female-bulkhead-type-a-male-05m
I've seen smaller lengths elsewhere.
Use a template: https://www.thingiverse.com/thing:25505
https://www.onlinelabels.com/clip-art/connector-db25-100661.htm

You can mark with a permanent ink marker Staedtler 318-9 Fine or Superfine
You can erase the marks with methanol.

Drill one mounting hole. Align and attach connector, before drilling more holes.

To mark points 1/2, 1/4 etc. Use ruler on diagonal and pick some number convenient. E.g 9" place on a diagonal and mark at 3, 6 and 9. Make marks like "V"'s

6" metal macinists ruler
Combination square
Coping saw

Automatic center punch
Digital caliper
1582405959184.png

Transfer punch. Cheap on the 'bay.

Deburring tool: https://www.mcmaster.com/deburring-scrapers

Each tool will make things more and more professional.

Where I 'worked', I had the luxury of a BNC punch, but not a D connector punch. I also had access to a full machine shop.
I bought the same Bosch jigsaw that we had a work. That can also be used. Use double stick tape on the base with the release paper left on. It won;t mar the surface.

I also have a Fein multi-master. There are knock-offs now.

With the Dremel, you can probably make an "D" type holes you need.
You could do a flange SMA so you can use a round hole and have anti-rotation.
1582406816063.png

Printing the front panel 1x made from a CAD program is really the way to go.
 
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True. Guess I paid too much. https://www.automationdirect.com/adc/shopping/catalog/tools_-a-_test_equipment/hole_cutting_tools/step_drill_bits_(hss,_hss-tin_-a-_co_5)_-_fractional_size/high_speed_steel_(hss)_tin_coated/101026ustro I got a case.

I down some Harbor freight stuff. I got one of their $6.00 multimeters for free from a power supply manufacturer. Use it to test batteries.

Got a pole saw.

Have tarps.

I have a Sawsall from them. I use it to cut tree limbs, galvanized pipe and help dig out stumps and make ham steaks with a stainless meat cutting blade.

I have an inspection camera from them too.

They are like 12 miles away.

Then there is this https://www.amazon.com/DEWALT-DWD460K-2-Inch-Bind-Up-Control/dp/B001P5CU2K/ puppy for a drill.

and this https://www.amazon.com/Bosch-11316EVS-SDS-Max-Demolition-Hammer/dp/B00004SUPW puppy with a case.

and this for a jig saw: https://www.protoolreviews.com/tools/power/corded/saws/jigsaw-bosch-1590evsk/830/
 
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Thread Starter

DarthVolta

Joined Jan 27, 2015
389
About what would all the chips/PCBs/connectors cost at a reasonable price ? $100-200 ?? I never ordered a PCB, nor quality parts from digikey/etc
 
PCB's can be cheap or expensive. Each fabricator has it's own design rules that need to be followed. Fortunately, you don't Have to lay out the boards. Files are sent to the fabricator and they produce a quote or a list of violations. generally, you have to get more than one.

Large sizes. 5 layers are going to cost you more. The fabricator can also provide a "stencil". This can be a polymer or steel. ou then use this to squeegee solder paste through the mask. You then place the components and solder or should I say heat the pads. The simple version.

Hobbyists might modify a toaster over with the suggested heating profile.

I actually had to re-flow a formatter board for my HP printer. It was like, remove stickers, heat oven to a specific temperature. Check with thermocouple. Insert board on high standoffs. Heat at temperature for like 10 minutes. Let cool overnight.

There is a rather large IC on the board using a BGA package (ball gate array). little blobs of solder keeping all of the connections under the IC. In manufacture, some of these joints were effectively a "cold solder joint" because the temperature time profile wasn't right.

The no lead solder is harder to work with. There is a lead free alloy with a small amount of Bismuth which is pretty nice.

IC's these days can get really small. e.g 1mm x 1mm. It's also possible to have in excess of 20 layers and even components embedded inside the PCB.
 
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