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Old 6th January 2014, 08:57 PM   #3501
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Quote:
Originally Posted by Noodle88 View Post
Merlin,
Have you tried LL2745 for your 26 preamp?
With 5.6:1 step down, lower output impedence will better match with your low impedence AVC.

Cheah
No, I haven't tried. I used the TVCs with SS mono amps (Erno Borbely "Millenium" 75W RMS Class A) so I didn't used tube amps (can match better, but I don't know).
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Old 11th January 2014, 01:00 PM   #3502
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Hi Magz,
beautiful work !

There are pretty 26 bijoux here...

B r u n o
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Old 2nd June 2014, 01:50 PM   #3503
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hi Felipe,

1. The scope pictures are input and output?

2. If the gain is not correct, maybe the transformer is not wired the way you intended. If you need help with the wiring, you must give us a link to the exact model of transformer you have, and draw exactly how the transformer has been connected. With Lundahl, it's more complicated than with other maker's parts.
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Old 2nd June 2014, 02:44 PM   #3504
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Yes the scope are input & output.

Attached Lundahl PDF.
Attached Files
File Type: pdf Lundahl LL1660 interstage transformer.pdf (37.6 KB, 20 views)
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Old 2nd June 2014, 02:56 PM   #3505
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Interstage transformer pics, cotton wire are input/output to anode, red wire are signal output-
Attached Images
File Type: jpg WP_20140602_005[1].jpg (388.5 KB, 280 views)
File Type: jpg WP_20140602_006[1].jpg (352.0 KB, 239 views)
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Old 2nd June 2014, 02:57 PM   #3506
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If the vertical (Voltage) scale on the scope pics is the same for In & Out, Then it looks nearly 2x gain.

Does it sound good?
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Old 2nd June 2014, 03:05 PM   #3507
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New pics of LL1660 wiring B+ & anode
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File Type: jpg Lundahl LL1660 Alt Q 4.5 = 1 wiring.jpg (396.8 KB, 83 views)

Last edited by merlin el mago; 2nd June 2014 at 03:09 PM.
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Old 2nd June 2014, 03:11 PM   #3508
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New pics of LL1660 wiring signal output & output ground.
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File Type: jpg Lundahl LL1660 Alt Q 4.5 = 1 wiring.jpg (404.7 KB, 59 views)
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Old 2nd June 2014, 03:16 PM   #3509
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Quote:
Originally Posted by Rod Coleman View Post
If the vertical (Voltage) scale on the scope pics is the same for In & Out, Then it looks nearly 2x gain.

Does it sound good?
Yes is the same vertical scale voltage, yes looks near 2x gain but when I no connect the 26 and only use the TVC sounds louder....checked the TVC and there is no gain 1x
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Old 2nd June 2014, 04:13 PM   #3510
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Rod discovered the issue, right channel doesn't amplifies the signal. Any idea where to start to fix?
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