From p. 24 of http://focus.ti.com/lit/an/slma002/slma002.pdf An alternative to attaching the thermal pad of the package to the thermal land of the PCB with solder is to use thermally conductive epoxy for the attachment. This epoxy can either be dispensed from the liquid form with a...

http://wombat.doc.ic.ac.uk/foldoc/fo...&action=Search See the second definition. Implies that the the prescribed procedure, component usage or design approach is 'standard operating procedure'.

In reviewing your first post, if you are building a bi-polar power supply like the one employed in Kevin Gilmore's solid state class A amplifier, the term virtual ground does not apply here. In this case, you have essentially two power supplies with the positive output on one tied to ground...

Quote: Where should I connect the virtual ground to? to DC ground of your amplifier which may or may not also be physical ground. Quote: Will there be any electrical problem building the power supply on a perfboard rather than a PCB board? Generally no so long as your...

It's always a good idea to use a ohmmeter to verify the pin assignments even if you have a schematic, especially if you are not 100% sure that the schematic applies to your pot.

This is an interesting topic. Most estimated prices of a PPA are based on building with what I consider (IMHO) premium or near premium componentry. But what if one were to use only basic componentry - using Tangent's board and a single set of Intersil buffers for starters. Then populate...

Go to the Tennis Warehouse forum on strings Much advice available there.

It does indeed look like Cu indexes have taken a big jump in the last few months: http://futures.tradingcharts.com/chart/CP/44

Looks like spiders playing 'Twister'

Quote: I have also sent that page off to the supplier to ask why they marked "PASS" on the inspection form when there were clearly scrapes and scratches on the leads (which is something specifically mentioned on the inspection form). Perhaps the scrapes and scratches resulted from...

There has been much discussion about the Gilmore Class A amp's PS. Kevin Gilmore himself allows that it may be overkill. I and others have used considerably less complex and less expensive designs with good success in our own implementations of this amp. Some people have experienced...

If you look at the prototype Gilmore amp in the Headwize article, you will see that it uses a conventional laminated core transformer which is not a toroid. It has two secondary windings. You could also use two separate transformers. The picture you show is of a production amp using a...

OT: Quote: My cables are made from the purest copper ore, which is lovingly spoon feed to Tibetan Monks. Only after years of meditation have these Monks learned to crap out the finest long crystal copper wires, which are then annointed in oil by blond virgins from Norway. The insulation...

Sorry for the thread diversion. In order to reduce microphonics or acoustic coupling, I would think a dampening design would be more useful than something based on magnetic repulsion which is more spring-like than dampening. As an example, just having springs in the suspension of your car...

Are you sure they are anodized and not just polished and clearcoated? If the latter, you can strip them with paint stripper and hand polish, then re-coat. Anodyzing is a process involving nasty acid and electricity. There are DIY kits; search the web.

Quote: I also fail to see how these help with vibrations originating within the unit or from the air (i.e. sound!). Me too. Besides, how does mechanical energy from vibration affect electrical energy from your typical component? The only possible use I could see is if you have a...

Your soldering technique may have to adapt to some variables: -the relative size of the PCB land that you are soldering the component to -the thermal mass of the component lead (usually insignificant, but can be an issue if you are soldering a large wire or component with heavy gauge lead)...

Here are some basic things you need to know before you start on ANY electronic project:The units of measurement for resistors and capacitors and how to read these off the components (some of which are small) How to determine what the three leads coming out of a semiconductor are and how to...

Can it be done as a first project by a rank beginner? Anything is possible; the question is what do you do if it doesn't work even after you've done a bang-up job soldering the components? There are numerous threads where it is evident the novice builder spent innumerable hours trying to...

All of these posts make me glad I have an Archos Jukebox. Batteries: industry standard 1.2v AA NIMH. Less than $2 per cell, 4 required, capacity up to 2300mah. Replaceable in under a minute. Hard drive: Industry standard 2.5" disk, 9.5mm height drives. Now up to 80GB for under $200. I...

Are you working near a fluorescent light or appliance? If all the wiring is excessive in length, you can sometimes pick up an induced hum from a nearby transformer, fluorescent fixture or even your computer. With the amp uncased and with the signal leads exposed, you may very well be...

Even with the blurry picture, it looks great. Part of the fun is seeing the artistry that some of the DIYers have demonstrated in casework. After all, even the now common Altoids case was an imaginative solution to enclosing the pocket amps.

Quote: the metalwork ive down, woodwork, Nothing wrong with stating that - a good part of making a DIY project memorable is the finish work - enclosure work, wiring. Any experience or tips helps those of us who have strengths in some areas of assembly but could use help in other...

Headphone stuff: Three Gilmore class A modded for lower operating voltages, one PPA Other: Many computers TV set (Heathkit) Many stereo amps/preamps Various radio control sets including servos Oscilloscope, other test equipment like DVM, FETVM, optical tach Many power supplies and...

Quote: I have <10mV DC on each channel. Which is acceptable for most any headphone Quote: The offset fluctuates (may be thermal With the servo in place, it should settle to a more or less steady state after a few minutes. Quote: How much of the DC offset will...