OK, So I have removed the brown wire from the RCA to Earth and I connected the top plate to Earth.
Now it is motorboating, UGH, So it appears with any number of connection variations I can make this thing Scream, Motorboat or Humm.
I'm gonna take a break for the night, Thank You All.
Now it is motorboating, UGH, So it appears with any number of connection variations I can make this thing Scream, Motorboat or Humm.
I'm gonna take a break for the night, Thank You All.
Have you checked all the voltages? In late July I sent you a bunch of SPP stuff including a spreadsheet that has every voltage you can measure on a SPP when using a 600VCT Edcor. Your voltages will be higher with the Hammond but should be close.
I don't know if you received this information or not since you didn't reply.
I don't know if you received this information or not since you didn't reply.
Here is how I managed a hum free SSE.
Move the input RCA's as far away from the pt as possible. Now as for grounding what I ended up doing after numerous configurations was to do the following.
1. Power inlet earth to chassis point
2. On the PC board I ran a wire from the terminal for the xformer CT which is also the ground connection for an aux capacitor to the star ground point.
3. All rca connections are very short twisted pair from the rca to the board...that's it.
You may want to test a setup like this with your RCA's with short leads coming out the front of the amp underneath just to see. I don't like the long run you have going across the chassis.
And I assume you are testing with the inputs shorted?
Move the input RCA's as far away from the pt as possible. Now as for grounding what I ended up doing after numerous configurations was to do the following.
1. Power inlet earth to chassis point
2. On the PC board I ran a wire from the terminal for the xformer CT which is also the ground connection for an aux capacitor to the star ground point.
3. All rca connections are very short twisted pair from the rca to the board...that's it.
You may want to test a setup like this with your RCA's with short leads coming out the front of the amp underneath just to see. I don't like the long run you have going across the chassis.
And I assume you are testing with the inputs shorted?
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My see is very loud with an open input.
Also...be careful connecting a device on checkout...I lost an iPod by accidentally sending 40vdc to the headphone jack through a the cable adapter.
I now always short the inputs with alligator cables
And if you use that ground scheme make sure there are no other ground points to earth or you will have a loop.
Also...be careful connecting a device on checkout...I lost an iPod by accidentally sending 40vdc to the headphone jack through a the cable adapter.
I now always short the inputs with alligator cables
And if you use that ground scheme make sure there are no other ground points to earth or you will have a loop.
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No I didn't get the info.
I've sent a copy of the original email.
I know it's been a while since anyone has posted a reply to this but...
Can you recommend an Edcor transformer that is equivalent to the Hammond power transformer? Or if that isn't the way to interpret this can someone tell me which Edcor transformer would work? I read the TubeLab pages and I just don't get it. I'm new to trying to learn electronics...been a Mechanical Engineer all my life. Sorry for the trouble.
Can you recommend an Edcor transformer that is equivalent to the Hammond power transformer? Or if that isn't the way to interpret this can someone tell me which Edcor transformer would work? I read the TubeLab pages and I just don't get it. I'm new to trying to learn electronics...been a Mechanical Engineer all my life. Sorry for the trouble.
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Sprags,
This is for a Tubelab SPP build?
2 options I found from Edcor:
https://edcorusa.com/xpwr172
https://edcorusa.com/xpwr131
The Edcor XPWR172 has a lower voltage rating (your B+ likely to be slightly lower), but is rated for 200mA vs minimum George's minimum recommendation of 175mA.
The Edcor XPWR131 has voltage rating of 660v which is slightly higher than 650v mentioned by George, and the current rating is on par at 175mA.
6.3v and 5v rails are adequate for both of the transformers.
This is for a Tubelab SPP build?
2 options I found from Edcor:
https://edcorusa.com/xpwr172
https://edcorusa.com/xpwr131
The Edcor XPWR172 has a lower voltage rating (your B+ likely to be slightly lower), but is rated for 200mA vs minimum George's minimum recommendation of 175mA.
The Edcor XPWR131 has voltage rating of 660v which is slightly higher than 650v mentioned by George, and the current rating is on par at 175mA.
6.3v and 5v rails are adequate for both of the transformers.
Check this thread post #9 in particular...it is my el84pp amp...not the simple pp but specs should match. This amp holds the voltages nicely.
http://www.diyaudio.com/forums/tubes-valves/171386-anyone-ever-made-el84-p-p-circuit-referenced-tubecad-journal-site.html
http://www.diyaudio.com/forums/tubes-valves/171386-anyone-ever-made-el84-p-p-circuit-referenced-tubecad-journal-site.html
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