geoff004
Well-known member
Here it is - from this thread:
http://www.groupdiy.com/index.php?topic=50529.0
I followed the schematics posted for the audio path and for the B+. The voltage reading I got came in at +171v. For the heater voltage I simply used a common LM317 circuit. For some reason I'm not getting a full 6.3v out of the LM317. I only used one of the 6.3AC windings on the transformer. Mine measured at around 5.9v. That's fairly close to 6.3v and the unit sounds good, so I probably won't worry about the last 0.4v.
Did I mention this thing sounds great!
I have accumulated a lot of parts over the years so I tried my best to use what I had on hand.
I'll try to post a parts list later on when I've got a little more time.
For the essentials:
Case is from Dan Deurloo
Power transformer is from Antec Inc.
Output transformer is the Edcor mentioned in the thread above.
I was concerned about getting the whole thing together and having noise from the PSU but there seems to be absolutely none. I didn't have to rotate the transformer or do any shielding.
I wired jumpers in the socket before mounting - 4->9 and 1->6. One is high and the other is low.
The only reasonable way I found it would all fit was by turning the transformer on it's side. It's mounted by a piece of aluminum which is bent at a 90 degree angle and screwed to the bottom of the case. For the power section I had some old tag board - it turned out to be the perfect length.
For point to point it doesn't get much simpler than this. I glue the caps down so they won't go anywhere.
One thing to note is to remove the paint in the case at the grounding points to ensure good metal to metal contact.
http://www.groupdiy.com/index.php?topic=50529.0
I followed the schematics posted for the audio path and for the B+. The voltage reading I got came in at +171v. For the heater voltage I simply used a common LM317 circuit. For some reason I'm not getting a full 6.3v out of the LM317. I only used one of the 6.3AC windings on the transformer. Mine measured at around 5.9v. That's fairly close to 6.3v and the unit sounds good, so I probably won't worry about the last 0.4v.
Did I mention this thing sounds great!
I have accumulated a lot of parts over the years so I tried my best to use what I had on hand.
I'll try to post a parts list later on when I've got a little more time.
For the essentials:
Case is from Dan Deurloo
Power transformer is from Antec Inc.
Output transformer is the Edcor mentioned in the thread above.
I was concerned about getting the whole thing together and having noise from the PSU but there seems to be absolutely none. I didn't have to rotate the transformer or do any shielding.
I wired jumpers in the socket before mounting - 4->9 and 1->6. One is high and the other is low.
The only reasonable way I found it would all fit was by turning the transformer on it's side. It's mounted by a piece of aluminum which is bent at a 90 degree angle and screwed to the bottom of the case. For the power section I had some old tag board - it turned out to be the perfect length.
For point to point it doesn't get much simpler than this. I glue the caps down so they won't go anywhere.
One thing to note is to remove the paint in the case at the grounding points to ensure good metal to metal contact.
