Posted by SteveBrown [ 155.188.183.6 ] on May 07, 2007 at 08:18:42:

In Reply to: For those who can't find the schematic Steve and I talked about posted by bill epstein on May 06, 2007 at 18:34:54:

As we talked about, a number of changes were made to this. Here are the ones I can recall off the top of my head...
1. We made it a stereo amp, so the power transformer has better current rating to accomodate that (I'd suggest 100ma or so min, 150 better).
2. R8 change to 25w
3. C5 change to Solen 47uf, 250v
4. R2 & R4 are tantalum
5. Change SS diodes to a 5AR4 (you'll need a 5v, 3a winding on the PT to do this, but well worth it)
6. Change C1 to 20uf, Solen, 630v
7. We made a "dual mono" supply by adding a second choke after C1 and then an additional C2 for the second channel
8. Make R10 270k, 5W
9. C6 is 10uf Obligoto oil cap
10. Use a Hammond filiment tfr w/dual 2.5v, 2.5a secondaries for the two 45's.
By the way, with some minor changes, the iron and power supply will certianly support using 2A3's instead of 45. You'll need to change the cathode R on the output tube to do this. Also, remember, we're shooting for 10ma and 150v on the plate of the driver.

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