tropicalrips 0 Report post Posted May 17, 2004 my latest pocket amp commisioned a fellow member nothing radical here, just a basic Cmoy this board has the option of upgrading to an A47, with the extra IC holder built-in, all the circuit is also there, all thats needed is another op-amp and it becomes an A47 layout is basic, with all the refinements of my previous amps, OPA2132PA op-amp, mini Alps 10k pot , plastic Hammond case , 4 X 330uF power caps , 0.68uF signal coupling caps & a TLE2426 rail-spliter. mini on/off switch & power jack for running the amp from an external power supply. the amp drives my SR80 surprisingly well even as a Cmoy configuration may not need it as an A47 after all Share this post Link to post Share on other sites
wil 0 Report post Posted May 17, 2004 Woooooo very,very nice!!! (psss....when can i get mine? lolol ) Share this post Link to post Share on other sites
N@Z 0 Report post Posted May 17, 2004 How does it sound with external power? Any hum? Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted May 17, 2004 How does it sound with external power? Any hum? non that i can hear... i think the rail-spliter & 4 power caps helps to reduce noise from the AC wall adaptor my previous "skeleton amp" with power supply hum problem comes from a ground problem and the input signal caps being way too big...30uF Alcaps...they pick up noise from everywhere & everything, once i place the amp in a metal case the humming goes away Share this post Link to post Share on other sites
jasonhanjk 0 Report post Posted May 17, 2004 Nice to hear that. Share this post Link to post Share on other sites
Sipher 0 Report post Posted May 17, 2004 very neat layout Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted May 17, 2004 (edited) a fellow member ask me for the schematic on the A47, i will post both the Cmoy & A47 here for all to see Cmoy pocket amp Apheared's A47 or buffered Cmoy amp Edited May 17, 2004 by tropicalrips Share this post Link to post Share on other sites
huihong 0 Report post Posted May 17, 2004 hmmm rips where did you learn how to construct an amp like this? Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted May 18, 2004 hmmm rips where did you learn how to construct an amp like this? from Jason u should see the thread for the first cmoy i built "question regarding Cmoy amp" over 200 post Share this post Link to post Share on other sites
huihong 0 Report post Posted May 18, 2004 heh yeah i saw that thread already, but i couldnt understand a single part lol you guys have have some sort of engineering background right? Share this post Link to post Share on other sites
jasonhanjk 0 Report post Posted May 18, 2004 Learn some electronic during poly days.... Share this post Link to post Share on other sites
jasonhanjk 0 Report post Posted May 18, 2004 If I remember correctly, tropical is not from engineering. It is really impressive to see someone not from engineering to build Cmoy, remind you he don't just build 2 or 3 unit... Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted May 18, 2004 i hav some electrical/comms & IT background but not in electronics i did sent a few op-amps to IC haven when building my amps Share this post Link to post Share on other sites
seiko_citizen 0 Report post Posted May 18, 2004 well i try to build cmoy amps, but usually takes a long time to construct so i no longer bother, but sometime i will try Share this post Link to post Share on other sites