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Model 640 code 121 : all cathode to ground on my radio
#8

Hello,

The push-pull is singing for the first tome this evening. It works great.

I wind the interstage transformer.

2100 turns of 0.1mm enameled wire (something like 38 AWG for you)
and 2 secondaries of 5250 turns each, with the same wire.

FOr the output transformer, I know... It's a shame... I use a power transformer Icon_rolleyes I left the primaries unwired, I only use the secondaries.
The speaker is on the 6,3V filaments winding. And I use the 2 high voltage winding of 2 x 280V for the primaries. It works fine. The sound is very loud and clear. With an ohmeter, I see 680 ohms with these 2 winding, like the schematics. That's great.

Everything is working right. lot of works but it was worth it.

Now, I've to work on the cabinet.... But after the holidays :-)

Best regards
Frederic ABIGNOLI


Messages In This Thread
640 grounded cathodes - by AI2V - 06-22-2007, 10:09 AM
[No subject] - by Ron Ramirez - 06-22-2007, 11:07 PM
[No subject] - by fabignoli - 06-23-2007, 12:45 PM
[No subject] - by fabignoli - 07-06-2007, 09:47 AM
[No subject] - by Ron Ramirez - 07-07-2007, 06:13 PM
[No subject] - by fabignoli - 07-09-2007, 05:01 AM
[No subject] - by fabignoli - 07-15-2007, 06:23 PM
[No subject] - by fabignoli - 08-11-2007, 02:16 PM



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