Millett "Starving Student" hybrid amp - Page 37

Even starving students need their vitamins

Even a starving student could afford $5 for a pair of vitamins from beezar.com : )

Beezar.com

Does anyobody have a recommendation as a replacement for the IRF510. They are a PITA to find locally here.

I can source the IRF540 quite easily - any thoughts on this as a replacement.

What should I be looking for in the spec sheets?

That's true. But I suppose if you want to save some extra money for beer, you could settle on the Russian PIO caps for $2.

Russian K42Y-2 PIO 0.10uf, 160V

I have a box of IRF610 heading my way. I _think_ they will serve (experts?).

I think your valves and power supply will now be coming through me, so I can chuck a pair of IRF610 in the package if you like.

A quick look at the data sheets makes me think that the 610 and 510 are not interchangeable. It'd be wise to get more knowledgeable feedback from someone before using them.

I don't know if it's been asked, but is this a good first time DIY project? It looks fairly simple? Also is there a good book on building circuits? I'm currently reading Teach Yourself Electricity and Electronics, which was recommended in another thread, but it doesn't talk about actually putting something together.

Scompton have you seen these videos? Tangent Tutorials

I've gone though all of them and I've done a minimal amount of soldering, mostly reterminating headphone cables. Building a CMoy doesn't interest me to much because I don't have much interest in a portable amp. If need be, I can build a CMoy first and give it away, but I thought this amp didn't look hard to build.

If you're point out the tutorials in response to my request for a book, they don't deal with tubes and heat sinks and such. For example, I know I saw a post on this thread about how to tell which pin is which in an unlabeled tube socket. I thought it would be nice to have a book that has this type of information in it, if such a thing exists.

I am very new to this, too. I have no engineering background. I'm a writer.

Here are the things I did not know, when I started:

* How to figure out which pin is which on the tubes and, particularly, the MOSFET -- I think that was answered in this thread (for MOSFET, from the front (the side without the metal plate), 1,2,3 left to right. One thing I found helpful (though not, oddly, in this situation), is that for every part on Mouser, you can get a link to the manufacturer's data sheet for that part.

* How to convert a circuit diagram into an efficient point-to-point layout. For this and for the tube orientation, I found the high-resolution images of the original builds and some other folks' builds made it possible to "borrow" how they did it. OK, a shameless copy. But heck...

* Thermafilm MOSFET mounting kits require thermal goo on the MOSFET and heat sink sides. Thermasil kits don't.

* As other folks have pointed out, but I had to learn for myself, the casework can be harder than the circuitry. I have no skills in this regard, either, but managed to make a tidy-looking amp (until I tried to paint the top after it was assembled, that is : )

I built a bottlehead.com S.E.X. amp as my first tube amp. It's a bit more complicated (for fitting things together as well as the circuit), but it's a stunningly nice-sounding amp and has meticulously illustrated instructions designed so anyone can build it, comes with all the required parts, down to shoulder washers, and has a good support forum. I think that was a good prep for the SSMH.

I've said this before and I'll say it again about this design: If I can do it, you can do it! And it's really worth it!

As others have said, this is a pretty easy build. I pretty much learned how to read schematics while building this, and didn't have any problems (other than the tube/mosfet numbering, which I figured out from the pictures of other people's builds). You'll probably be fine with this as a first build.

And on another note, I went to a local surplus store today and picked up 3 different pairs of replacement tubes, all different brands. And 2 of the pairs got rid of a slight humming problem I was having. The other pair just made it really bad. So now I have some replacements if/when my tubes fail.

I have a couple of questions regarding heatsinks.

I cant find any mounting kits and wondered if it was possible to just bolt the ir510 directly to the sink. I have some white compound left over from my dual core processor which I could smear on the heatsink if this would help.

Also will there be a problem if my heatsinks arent on show, ie I put them inside the case (hammond 1455 or similar)

If you don't use mounting kits, then the center pin of the mosfet will be tied to the heatsink... which isn't a problem, as long as the heatsink doesn't have continuity with something it's not supposed to...

Like anything, including ground

.