Comments on: They Don’t Call it Hardware for Nothing

By: mary

mary — Sat, 28 Feb 2009 13:55:58 +0000

I’m 40 and just completed My Clifford.. he was my first little electronic thingy.

I felt lost most of the way but found a couple of pages that really helped me in trying to find out what resister was the one to use.

http://samengstrom.com/nxl/10116/5_band_resistor_color_code_page.en.html the above page really helped me sort out which was which.

(as they pretty much looked the same to me).. Plus i might need a magnifying glass to see the lines better.. (gosh i might be getting old – ack!)

Ps the diodes look fine.. on the instructions it said A was the positive side and K was negative.. so it looks like you have them the right way around.

Mine works pretty good.. just i was hopping for a better sounding chirp.. hope i have helped in some way .. Cheers Mary.

By: Alan Green

Alan Green — Sun, 25 Jan 2009 20:41:44 +0000

This is a stretch, but did you check the errata on the Silicon Chip web site? http://siliconchip.com.au/cms/A_104479/article.html

By: alastair

alastair — Mon, 19 Jan 2009 22:04:37 +0000

On the subject of DealExtreme, as on many other subjects, Dan has worthwhile things to say.

Martin: I have no idea why your comment got marked as spam. I use the Akismet distributed spam detection system which I was moderately happy with the two false positives. I hate false positives. Not sure what I'm going to do about it, but I know I'm very reluctant to implement CAPTCHA or any other nonsense like that.

By: Martin

Martin — Tue, 13 Jan 2009 13:19:49 +0000

You're better off removing the transistors from the circuit to test them.

With regards to testing voltages at various points, if it's not marked on the circuit, you'll need to calculate the expected voltage at various points based on the circuit diagram.

(On another note....any idea why my comment got flagged as spam? Was it due to the fact that I had an embedded URL in the text...or was it something else?)

By: alastair

alastair — Mon, 12 Jan 2009 23:18:55 +0000

Apologies to marxy and Martin, whose comments I had to rescue from the spam bin…

@marxy: I saw that errata; it had been applied to the diagram supplied in the kit.

@Martin: I also saw that hint (and in fact linked to it in the post!)

I’ve got a circuit diagram but am not really familiar enough with reading it to know how to do troubleshooting.

For example, how do I read it to know what the voltage should be at various points? Also, if I want to test a transistor in-situ, is that even possible? (Current theory is that I’ve fried one of them while soldering).

By: alastair

alastair — Mon, 12 Jan 2009 04:30:52 +0000

Sunny: Nup, I’m pretty sure the circles are there to remind you to mount the component vertically, as I have done with the resistors. For whatever reason I didn’t mount the diodes vertically as well.

By: Sunny Kalsi

Sunny Kalsi — Mon, 12 Jan 2009 04:12:49 +0000

If the "A" denotes the "anode", then what do the circles mean? Could it be possible that the "A" simply means that the circle is the anode (as oppposed to "K" and a circle)?

By: alastair

alastair — Sun, 11 Jan 2009 20:16:04 +0000

Err, which one? Both have the non-striped end aligned with the A (for Anode) markers.

By: alphajuliet

alphajuliet — Sun, 11 Jan 2009 11:02:38 +0000

One of your diodes looks the wrong way around.

By: Martin

Martin — Sun, 11 Jan 2009 07:51:46 +0000

Without a circuit diagram for clifford, it's a bit hard to troubleshoot it remotely ;-)

However, according to this page, some things to check include:

check that you haven't transposed Q1 and Q2
check the orientation of D1 and D2
check your resistors

(Note that the silicon chip page is wrong when it says "the anode (A) is the end of the diode with the stripe. Both anodes for D1 and D2 should be toward the 3.3kΩ resistor." The anode is the end of the diode without the stripe! Assuming the screen printing on the top of the PCB is correct, then both your diodes are oriented correctly.)