I'm not Wayne, but I can answer the question - the 4N35 is a "jellybean" part, merely make sure you get the right package, DIP-6
http://www.mouser.com/ProductDetail...=sGAEpiMZZMteimceiIVCB91xDxNLJbU2Xl5QMW1lqH0=
http://www.mouser.com/ProductDetail...=sGAEpiMZZMteimceiIVCB91xDxNLJbU2Xl5QMW1lqH0=
I have completed the assembly and testing of the rev. 3 board. It is now running and sounding very fine indeed. Thank you again to Wayne and Jim for this great project.
The LM317 and LM337 were used in place of the 7815 and 7915 respectively. The LM337 drops right in but the LM317 substitution required 4 cuts and jumpers to the underside of the board. For +-15V R10 and R14 chang to 200 ohms and R9 and R13 change to 2200 ohms. I chose to reduce C8 and C10 to 22uf/25V. D5 and D6 were deleted.
The output MOSFETs are IRF9510's from an old stash of Harris parts, and IRF610's. I have 10 each of the 2SK2013's and 2SJ313's but I am saving those for a large BA-3B project that is in progress.
The opamp is an OPA2134 which is all I had on hand. I am surprised at how difficult it is to find stock on the OPA2604 at the usual parts suppliers. But I am looking forward to trying those and other opamps.
As an aside I found that my 25 watt soldering iron was seriously underpowered when trying to unsolder the thermals on this 2oz board.
The next step is mounting the board in a Hammond 1455 box. I have a attached a photo for those who disbelieve without proof (ZM) .The sharp eyed viewer will probably note the Aleph P knob which is swag from BA2007. The spiffy Neutrik output connector is a gift from JAM.
Graeme
The LM317 and LM337 were used in place of the 7815 and 7915 respectively. The LM337 drops right in but the LM317 substitution required 4 cuts and jumpers to the underside of the board. For +-15V R10 and R14 chang to 200 ohms and R9 and R13 change to 2200 ohms. I chose to reduce C8 and C10 to 22uf/25V. D5 and D6 were deleted.
The output MOSFETs are IRF9510's from an old stash of Harris parts, and IRF610's. I have 10 each of the 2SK2013's and 2SJ313's but I am saving those for a large BA-3B project that is in progress.
The opamp is an OPA2134 which is all I had on hand. I am surprised at how difficult it is to find stock on the OPA2604 at the usual parts suppliers. But I am looking forward to trying those and other opamps.
As an aside I found that my 25 watt soldering iron was seriously underpowered when trying to unsolder the thermals on this 2oz board.
The next step is mounting the board in a Hammond 1455 box. I have a attached a photo for those who disbelieve without proof (ZM) .The sharp eyed viewer will probably note the Aleph P knob which is swag from BA2007. The spiffy Neutrik output connector is a gift from JAM.
Graeme
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