DIY Thermal LPM for under $50

[lazeerer]

^^^ Nice Job Buddy looks AweSome.

:kewlpics:

 

[Xplorer877]

:thanks:

-Tony

 

[MarioMaster]

Nice work, using a spare diode heatsink?

 

[lazeerer]

Update:
So i ran into some problems with my LPM body. I Broke 2 screw threads off when screwing the bottom in the other day Because they were plastic and when i screwed the metal screws in i over titaned one one day and same the other and they snapped. So every time i would pick the LPM up the bottom was loose. It got annoying quick so i Gutted it and put it in new RadioShack Project box.

Its the (2 1/2" High x 5" long x 2" wide) Project Box.

It feels really solid, So iam happy that it wont Brake on me. I love this meter Just want to say :thanks: again MarioMaster for putting this project up.:beer:

Heres a couple Pictures:

 

[Xplorer877]

^ That looks great man! Nice job!
That's the same box I used, they're great.

-Tony

 

[lazeerer]

^ That looks great man! Nice job!
That's the same box I used, they're great.

-Tony

Thanks Buddy, For Sure there awesome and solid too, i dont think ill be stripping the screws or breaking this box even if i hit it with sledge hammer. LOL.

It was a little hard to work with to use that switch because of the size inside and the screen, But i managed to fit it in pretty nicely. I wanted to get the one step larger one but the next one they had was 4 times the size of this one.

But iam glad i got this one, Nice and small. I also like the metal plate that comes with it. It Gives it a nice touch.:beer:

 

[jib77]

I finally got the LPM PCB's from China, after a 2 month wait (MakePCB.com, really good quality and price but takes forever and you do not get any updates). On the same day I got another order I placed 2 weeks ago from a domestic source.

 

[TTerbo]

whos design is that??

 

[jib77]

Its the circuit from the OP w/ my layout and part selection.

 

[gillza]

Its the circuit from the OP w/ my layout and part selection.

Jib,

If it is not too much to ask could you please post the pcb file for your latest layout and the list of the components you have used.
I am a n00b in the electronics and I will be trying to follow your way of making this LPM. Thus the more details you can provide the better
I would also appreciate if you could post a link to the domestic PCB printing company.

Also would you consider selling one of the complete PCBs (with components mounted)?

Thank you very much in advance!

p.s. If someone could post a step by step guide for n00bs like me on how order this PCB (what to choose when ordering the PCB made) and where to buy the components, following by how to solder and assemble the unit, this guide would be worth a sticky and a gazillion of +REP points IMO

 

[jib77]

If it is not too much to ask could you please post the pcb file for your latest layout and the list of the components you have used.

Attached. I get my parts from Mouser.com because they happen to be in the DFW area(1day ground shipping ), but digikey is good too.
Any DIP8 package LM358 will do.
Any brand 1206 sized resistors and caps.
Bourns 3314 series Pots (multi-turn versions 3214/3224 will *barely* fit the 3314 pads)

I would also appreciate if you could post a link to the domestic PCB printing company.

1st choice:
>>Sunstone Value Proto Service<<

2nd choice if due date in within a week:
>>DorkbotPdx panel GB<<

Also would you consider selling one of the complete PCBs (with components mounted)?

Yup ... as you can see I have plenty. It cost the same to order 3 as it does to order 20 ... I'm going to sell them at $5ea + $1flat shipping(US), PM me.

p.s. If someone could post a step by step guide for n00bs like me on how order this PCB (what to choose when ordering the PCB made) and where to buy the components, following by how to solder and assemble the unit, this guide would be worth a sticky and a gazillion of +REP points IMO

Such a guide would be a serious undertaking, but needed ... but just a few points. Each board house and service level has their own requirement and options. If you have any questions about a particular option PM me. As far as soldering ... look for SMD soldering tutorials on youtube, flux is your friend.

 

[gillza]

Yup ... as you can see I have plenty. It cost the same to order 3 as it does to order 20 ... I'm going to sell them at $5ea + $1flat shipping(US), PM me.

Jib,

Thank you for the reply and for offer of help. Greatly appreciated!
Let me make sure though: you are going to sell the PCB with SMDed components for 6 dollars shipped in US? This sounds too good to be true

 

[jib77]

Jib,

Thank you for the reply and for offer of help. Greatly appreciated!
Let me make sure though: you are going to sell the PCB with SMDed components for 6 dollars shipped in US? This sounds too good to be true

PCB Only ... (no way I could do that ... each 3214 pot is $3.22!)

 

[gillza]

PCB Only ... (no way I could do that ... each 3214 pot is $3.22!)

PMed

 

[kiyoukan]

okay so i have been looking at using a panel meter.
I read that even if you buy a 20v on its just a resistor swap to make it read just 2v
Might someone be able to help with that?
I got mine working and i hope later this week i will be meeting up with someone who owns a real lpm.

 

[comradmax]

I read that even if you buy a 20v on its just a resistor swap to make it read just 2v

This is not always true! I bought a panel meter on ebay thinking the same thing, it's a 0-99.0V. I even had an email exchange with the seller about it. Their design did not have a simple resistor value feature for moving the "dot" Others do have that, look very closely at pictures of the PCB, sometimes they have an array of resistors labeled for diff ranges - in this case you can find a combination you need to read 0-0.999V.