BrianGT over at chipamp.com is celebrating the start if a new decade by offering customers a 20% Discount on all available kits during January 2010.

For those that have not heard of chipamp.com before, they supply a selection of high quality kits based around the National Semiconductors Overture series amplifier chips. 

Everyone likes a bargain, and Sparkfun, a company well known amongst amateur electronics enthusiasts really captured the attention of it’s existing and potential customers with a 100 thousand dollar giveaway on the 7th of January.

Offering to giveaway 100K of stock is surely a generous gesture indeed and no doubt should have won Sparkfun the admiration and adoration of many customers.  Well that’s what you would think.

Now I doubt that many people will be surprisedIt  to hear what happened next… Sparkfun’s servers crumpled under the immense self inflicted DDos attack, even before their giveaway had begun.  Now what should have been an incredible good news story turned into a massive digital lottery for those trying to access the site.

Long before the server’s had returned to anything approaching usability, twitter and other social networking sites started to buzz with disgruntled customers who had been unable to complete their orders, despite attempting for two hours to log in an check out their goodies!

It will be interesting to see how Sparkfun fares in the aftermath of what can hardly be seen as a successful campaign.  I hope that many will take the “I didn’t loose anything” viewpoint on this one. This is a company that had a lot of goodwill in the DIY electronics community, question is will the community be in a forgiving mood?

The Aleph is a popular Class-A amplifier design created by the now famous Nelson Pass.  Over at Chipamp, BrianGT created the Mini Aleph Printed Circuit board, originally a special for the DiyAudio community. As a thanksgiving special this PCB is available with 25% discount until the 31st of November 09.  

The Circuit board costs $6.75 (originally $9) and for that you get a single board that is scored to allow it to snap into several pieces; 2 main amp boards, and 4 output device boards.  Of course you will have to populate these boards and provide a power supply as well.  A Bill of Materials is available here and a suitable power supply boards is also available from Chipamp.com.

The main board will work in the mini-A configuration without any output boards, or in the Aleph30 configuration with the use of the output boards.  If you have been looking to build a high quality 30W class A amplifier.  A Schematic is available here.

Postage for PCBs: $8 US, $15 INTL for as many as you order

To grab one of the discounted boards follow this link

Over  at TwistedPearAudio, Russ White and Brian Donegan  have been busy adding yet another DIY Audio kit to their selection.  Twisted Pear this time have produced what Russ describes as a “Mostly Discrete Opamp”.  Or to put it another way a headphone amplifier! 

This kit occupies two printed circuit boards, one per channel and accepts either balanced line inputs or single ended operation.  The balanced line option is designed to interface with several of their other product offerings.  The Ventus can also easily be setup as a classic non-inverting amplifier with single ended input. It also can be setup as an in inverting amplifier with single ended input.

A German site has released details of how they repaired a set of Mission 753 Loudspeakers that were sporting a blown tweeter. 

Visitors to Justblair.co.uk frequently contact me for advice on how to deal with blown tweeters on the Mission 753 Speakers, it seems that the tweeters are the least resilient to party type abuse!

As the speaker is about 15 years old now, unsurprisingly the tweeters are no longer available as replacement parts.  This leaves the owner with two choices, either find a specialist who can rewind the melted voice coils or find an alternate part that will play nice with the bass drivers and crossover. 

When asked to repair a set of Mission 753’s Hifi Selbstbau took a methodical approach to find drivers that would make a good match to the speakers. 

Bruce Heron was looking to simplify the process of testing and prototyping his Tube designs.  When testing designs, a solder-less breadboard is a fantastic tool, for the hobbyist.  However I have never seen one that was either durable enough or indeed that has the correct connector layout to take a vacuum tube.

What Bruce did then was to layout a wooden board with the required connections for his tubes, a breadboard and other required components.  The board has connectors for inputs an a variable resistor.  Chock blocks are supplied for routing and components.

Bruce seems pleased with his proto-board and suggests a few more components you may consider adding if you chose to roll your own.  More pictures and some further details of the build are available at DIYAudioProjects…

DIY Vacuum Tube Prototyping Board

I got a hot tip from the Adafruit Industries Blog today that may be of interest to you.  Tektronix have an online PDF available for download, “XYZ of Oscilloscopes”.  II had a quick read through it this morning and it is an excellent guide on the subject.  The 59 page PDF covers the different Oscilloscope technologies, according to Tektronix