Continuity Tester Project

[MCU88]

The box looks really nice. Why not to use colors in the artwork?

Colour adds cost to the product. I only have a monochrome laser printer. It is a decent HP Laser Jet P2035. I did own an Epson four colour laser printer about 7-years ago but I wore it out. That cost me AUD 1,200 My priority at the moment with money is to purchase stock for an electronics hobby shop that I want to open somewhere between a year and 2-years time. I already have a lot of components (all the little bits & pieces comprehensive assortment) -- but must focus on importing tools next. Soldering stations. Desoldering guns. Oscilloscopes. Multimeters. Hand tools. I am probably going to do about 10K...

The thing with colour is that you must be carful not to use more than a few colours otherwise it looks cheap.

 

[MCU88]

The gals liked the thing. Made them smile.

That's the most important thing and the plot of life ...

Make lots of money and make all the gals smile...

Happy wife happy life is the saying.

 

[NorthGuy]

You can use a local printer shop. They will print you 100 labels for $10 or 20. It'll be a little bit more if you order self-adhesive.

 

[Tony Stewart]

Ω

Colour adds cost to the product. I only have a monochrome laser printer. It is a decent HP Laser Jet P2035. I did own an Epson four colour laser printer about 7-years ago but I wore it out. That cost me AUD 1,200 My priority at the moment with money is to purchase stock for an electronics hobby shop that I want to open somewhere between a year and 2-years time. I already have a lot of components (all the little bits & pieces comprehensive assortment) -- but must focus on importing tools next. Soldering stations. Desoldering guns. Oscilloscopes. Multimeters. Hand tools. I am probably going to do about 10K...

The thing with colour is that you must be carful not to use more than a few colours otherwise it looks cheap.

I love my Oki low cost colour laser printer from Tiger Direct, ignore it for months or a year, then use it and get no dry ink. But all personal printers are just a convenience as professional printing is more cost effective and higher resolution possible. I once made a glossy Black brochure for a company on heavy material with fully saturated colours for LEDs and got it printed across the street in 2400 dpi at low cost.

Having run my own prototype shop for SMD for a few years ( Wireless AMR support) I found many good sources for surplus inventory and places to buy that are ERAI registered. But sometimes you can create alerts on google for liquidation sales or even better find your local Selectronics or Board shop with excess inventory... They usually just scrap it unless someone makes an offer. They would never promote the sale.

At C-MAC one time, my Boss called me to go with him, we went to the scrap bin outside and tossed hundreds of surplus Nortel inventory of Reels of SMD passives into the garbage bin like frisbees for fun... He had a reason to smile as his adjusted depreciation costs,, make a profit.
But then C-MAC is no more in this business as they sold out to Solectron who sold out to Flextronics.

in another case of luck,,Guess where I got $3k of scrapped LED boards on mix of FR4 and aluminum boards. ( cost) for $20 ( intended for Police/Ambulence vehicle end-user)
So far only 1% failure rate which I can replace from spare boards.
scrap metal shop.... via Solectron

 

[Tony Stewart]

Without showing a common slider selector switch or mechanical design,

one can do an All in One Tester for < $1 in volume or more depending on how fancy the box is.

It can test diodes, LEDs, continuity for Hi R < 100 Ohms or Low Ohms <100 mOhms spanning a 3 decade range. by brightness of low power and high power LED.


Features max volt drop on continuity test of 0.5V or 500mA or less max approx. (depending on choice of power LED)
since ESR of 3W LED is 300mOhm an intermittent break from 0 to 100 mOhm would cause flicker in brightess as current modulates 30% easily detected.

Same with low power LED except at 100 Ohms down to 1 Ohm brightness changes. from 8mA max

Just whipped this together, but I know it works with Intensity controlled Resistance over 3 decades from 500 mA to 0.5 mA

Battery is Lithium CR123.
LED's are zener protected.
Resistor for LED test.
ESR shown for LO HI R test built into all LED's

 

[MCU88]

You can use a local printer shop. They will print you 100 labels for $10 or 20. It'll be a little bit more if you order self-adhesive.

Prefer to do it all 'in house' I wouldn't sell 100 either. I can print an monochrome self-adhesive in house for about 20-cents... I am thinking that I would do a run of about 10 units only for $29.95 ea on my shelf. Be lucky to sell one every 3-months. The profit on $29.95 is good though.

 

[MCU88]

Without showing a common slider selector switch or mechanical design,

one can do an All in One Tester for < $1 in volume or more depending on how fancy the box is.

It can test diodes, LEDs, continuity for Hi R < 100 Ohms or Low Ohms <100 mOhms spanning a 3 decade range. by brightness of low power and high power LED.


Features max volt drop on continuity test of 0.5V or 500mA or less max approx. (depending on choice of power LED)
since ESR of 3W LED is 300mOhm an intermittent break from 0 to 100 mOhm would cause flicker in brightess as current modulates 30% easily detected.

Same with low power LED except at 100 Ohms down to 1 Ohm brightness changes. from 8mA max

View attachment 92288

Just whipped this together, but I know it works with Intensity controlled Resistance over 3 decades from 500 mA to 0.5 mA

Battery is Lithium CR123.
LED's are zener protected.
Resistor for LED test.
ESR shown for LO HI R test built into all LED's

Too simple to sell as an KIT. Gotta have at least one IC or a couple of transistors and a half dozen resistors min. Otherwise there is nothing to build really.

 

[Tony Stewart]

Put in a schmitt trigger oscillator , with <100m Ohm Logic gate level Vgs=2V min. Mosfet , it will vary frequency with ESR and voltage suggest 1-5 Hz

Cheap AND reliable AND accurate, but must be 3.0V lithium cell thus is your precision Vref , the other is 2.85 Vref on LEDs for 1-5% rated current or 2.45V in Toshiba new power LEDs at 1% , Vmax is the difference , you see? Capiche? Mo better than yours

 

[Tony Stewart]

Economics says two for $25 will sell you 10x more of my design.

 

[jpanhalt]

What do realities matter? He is offering free coffee.

John

 

[MCU88]

Economics says two for $25 will sell you 10x more of my design.

The most expensive part is the box. Cheapest I have is what I have shown in the photos. The lids are snap fit. No screws. Dollar each to buy in quantity. I sell for $6.95 ea...

 

[MCU88]

What do realities matter? He is offering free coffee.

John

And FREE beer.

I wanna have an pinball machine in the shop too.

 

[MCU88]

Economics says two for $25 will sell you 10x more of my design.

Seriously though no matter what design I go with I will not sell many... There is no 'wOw factor' about an continuity tester. I think it would take me 3-years to move 10 pcs.

I am going to employ a hot looking girl wearing a mini skirt to serve people at the till. All parts bagged, labeled and priced. So no experience with electronics required. You just punch in the numbers on the cash register. So anyone could do the job you know. All the guys will come in just to have a perve on her. Truth serum in the coffee, so we will see what sort of nasty pieces of work we can expose.