# Project: 6-Digit LED Clock (Very Accurate)

#### T.Jackson

Joined Nov 22, 2011
328
:: Very Accurate Timekeeping of +/- 1 Minute p/Month ::

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#### Wendy

Joined Mar 24, 2008
22,647
Very nice. Ever think about doing a PIC tutorial, how you program your PICs?

I especially like the multiplex scheme.

#### T.Jackson

Joined Nov 22, 2011
328
Very nice. Ever think about doing a PIC tutorial, how you program your PICs?
I have been told that expression is my weakest point.

I especially like the multiplex scheme.
I formally studied this 20-years-ago.

#### T.Jackson

Joined Nov 22, 2011
328
I have enough memory remaining to include a calendar too. I have plans to use star burst displays for another version which can show letters and scroll reminder messages that the user programs in for an alarm function.

If run out of memory for even more features, then an EEPROM will be required.

#### T.Jackson

Joined Nov 22, 2011
328
You just sell some of the pre-programmed MCUs on ebay and make some money in exchange for letting us say whatever on here.

#### Wendy

Joined Mar 24, 2008
22,647
You may have noticed there is no advertising here. We are a prime target for spammers, but the owner of this site is a top notch hacker (in a good way) in his own right, and the moderators are very good at keeping on top of things. This site has survived several attacks where some others have fallen.

If you want to develop something commercial feel free. Self promotion for established members (which you have manage to achieve) is usually OK.

I have folks developed ideas they wanted to sell at no charge from me. So have a lot of other folks here. My offer to help you develop a PCB is still open, for example.

I made a point of this else where, but while we try for a loose grip on moderation, we are very firm on enforcing the rules. The primary one for me is no flaming. Nothing drives away a beginner trying to learn than heckling, so it doesn't happen here.

#### T.Jackson

Joined Nov 22, 2011
328
There is no copyright on anything that I post.

I too have to ability and the software (circuit maker 2000 / protel) -- to design PCBs.

#### T.Jackson

Joined Nov 22, 2011
328
I made a point of this else where, but while we try for a loose grip on moderation, we are very firm on enforcing the rules. The primary one for me is no flaming. Nothing drives away a beginner trying to learn than heckling, so it doesn't happen here.
There could be some language.

#### Wendy

Joined Mar 24, 2008
22,647
Nope. If there is I can edit it out.

The report system here means I don't have to see all, just respond to the members pointing things out.

#### MMcLaren

Joined Feb 14, 2010
853
I think it looks very nice too. I also know from experience how long it takes to hand wire something like this (grin)...

Cheerful regards, Mike

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#### Wendy

Joined Mar 24, 2008
22,647
Good design, nicely wired. Notice the sockets for the LED displays?

This would be the kind of project I would use for learning how to use a PIC.

#### hgmjr

Joined Jan 28, 2005
9,029
Impressive project. Workmanship appears to be extremely good.

Looking forward to more such contributions in the future.

hgmjr

#### Yako

Joined Nov 24, 2011
245
I think it looks very nice too. I also know from experience how long it takes to hand wire something like this (grin)...

Cheerful regards, Mike
About 3 hrs worth of work if he knows what he is doing. I have seen boards with dozens of chips on them all wired together with so many layers of wire wrap that you can barely see much else besides a red rat's nest

You may find that this person has background with old school prototyping. It used to be very expensive to go straight to PCB and discover errors, so many engineers produced the circuit on vero board first to make dead certain that it worked.

#### Wendy

Joined Mar 24, 2008
22,647
I make my own boards, it is not expensive at all. Just time consuming.

#### Yako

Joined Nov 24, 2011
245
Yeah, manually drawing neat looking PCBs can take some time, and it is an art in itself.

How long you figure to make a single-sided board for that clock?

#### Wendy

Joined Mar 24, 2008
22,647
About a week. If I had a couple of days off several days.

#### Yako

Joined Nov 24, 2011
245
I think about a few days too. Easier of course if going to double-sided. No wire links. This I find the hardest part. So many rip ups and re-trys to get everything in place.

Double-sided through hole plated with solder and sillkscreen mask expensive though.

Like, to sell this clock as a complete KIT on ebay, it would have to be under $30. Don't think that people would pay much more than this. Last edited by a moderator: #### Wendy Joined Mar 24, 2008 22,647 The boards I make are single sided, and I don't have any problem using wire jumpers. It is my norm. Home brewed boards like this run less than$5, the only hard part is the template for the board itself. That is where the time goes.

I was thinking of laying out one for this project.

How I make PCBs

#### MMcLaren

Joined Feb 14, 2010
853
I recall spending about six (6) hours wiring up the single chip six digit Charlie Clock/Calendar/Timer (below)... Whew!!! (lol)...

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#### Yako

Joined Nov 24, 2011
245
I suspect that I would be quoted something like around \$5 a piece for this on a quantity of 50 or so. Possibly a bit more. It isn't that much more expensive to have silkscreen printing and solder masking done too. This in turn would make it easier for constructors to build the project. Straight away knowing where all of the parts have to go without having to reference to a component overlay on a piece of paper.