Two new postings at hammer.ampage.org

[Mark Hammer]

I finished up a 2W portable amp last night for our family's cross-continent trip tomorrow (we'll be in a minivan somewhere between Ottawa and Victoria, BC for the next 3 weeks).  I took a couple of snaps and put them into a zipfile.  Two things of note. First, the rubberized running board paint is used for the rear panel.  Not the best picture of it but it will give you some idea of the texture.  Second, I stumbled onto a nice little heatsink for the 14-pin LM380 I used for the power section.  I thought folks would find it interesting.  The schematic is essentially a higher-power version of the PocketRockit, with diode clipping on the input stage.  I made the diodes (a 1+2 asymmetrical arrangement) switchable and tacked on a parallel cap so that when I grounded the diodes I'd get clipping plus some "rounding off" so that I wouldn't have to automatically adjust the tone.  I had intended to install a power-on LED but there's already too much to do preparing to leave.

(Note to those who think 2W is puny.  Tell that to the folks down the street complaining about the noise!)

The other posting is a zipfile with some pics that Dean Hazelwanter took of a somewhat larger Leslie unit that he has (10" speaker).  Dean did a nice job of disassembling it to gve a better sense of the mechanism and framework.  Thanks, Dean.  (Sorry I took so long, Dean.  I thought we had a zipping utility at work but had to bring one from home to install.)

As noted, I'll be incommunicado for a couple of weeks.  We hope to pop into some internet cafe's on the way to transfer pictures over from memory sticks to CDs, and maybe the family will let me use the rest of that hour to say hi to you folks before I have to drive them to some tourist trap.  I'll probably poke my head in some threads over the rest of this afternoon, but I'll just use this occasion to say bye and wish everyone a nice August without any tornados, hurricanes, floods, brushfires, or other cataclysms to sully their days.

Keep your thinking sharp, your attitude flexible, your strings clean, and your iron tinned.  I'll see you in September.

[Arno van der Heijden]

I have problems downloading the minamp zip...

[Lonestarjohnny]

Have fun Mark, and swat a few of them "NoSee'Um's" for me.
Johnny

[Doug_H]

I;lkjk

[Marcos - Munky]

Thanks for share the files, Mark. Really great mini amp.

[Dean Hazelwanter]

Actually, the speaker cutout for this Leslie 900 is a 15". I might make a reducer to use a 12", though.

[petemoore]

Sound sources directions are more detectabel with high frequencies...
 
 ""Actually, the speaker cutout for this Leslie 900 is a 15". I might make a reducer to use a 12", though.""
 
 They're making some pretty 'high endy' 15's these days, it'll be interesting to read if you post about the differences usin a 15 compared to a 12 speaker for leslie effect.
 I built some leslies and good high end seemed to increase the 'effectiveness'...

[Doug_H]

;lkj

[Mark Hammer]

Yup.  I fixed the link so right-clicking should work for all now.