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Old 24th May 2011, 02:28 PM   #991
massimo is offline massimo  Italy
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Correct Felipe.
Each tube must have its own reg powered by its own Xfrm, bridge and C-R-C
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Old 24th May 2011, 02:33 PM   #992
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Distrelec don't works in Spain, could I use this from RS:

Block | Transformadores | Transformadores | Transformadores para montaje en circuito impreso (PCB) | Encapsulado - Laminado, Serie FL (Salida Doble) |FL 30/6
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Old 24th May 2011, 02:46 PM   #993
massimo is offline massimo  Italy
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Muy bien! (very good)
If you wanna save few €, IMO you can also chose model 201-7303 (6V/4A) but don't tell Rod
Block Xfrm are very good. I bought the Hahn because they were cheaper.

Last edited by massimo; 24th May 2011 at 02:49 PM.
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Old 24th May 2011, 02:59 PM   #994
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Are out of stock till July
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Old 24th May 2011, 03:15 PM   #995
massimo is offline massimo  Italy
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As usual...... they write "Disponible en 48 horas" (available in 48 hrs) but when you try to order the item it suddenly become out of stock!

What about the smaller ones 201-7303 ?
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Old 24th May 2011, 05:31 PM   #996
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Quote:
Originally Posted by massimo View Post
As usual...... they write "Disponible en 48 horas" (available in 48 hrs) but when you try to order the item it suddenly become out of stock!

What about the smaller ones 201-7303 ?
These are out of stock till July 13.

201-7381 are in stock
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Old 25th May 2011, 06:48 AM   #997
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Felipe, here's a good 6V/50VA:

PRO POWER|CTFCS50-6|TRANSFORMADOR, 50VA, 2 X 6V | Farnell España

I think Farnell ship with no cost.
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Old 25th May 2011, 07:27 AM   #998
massimo is offline massimo  Italy
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Rod, one question: do you suggest to switch on the heaters Xfrms first (one switch) and the HT + rectifier heaters one after a while (another switch)?
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Old 25th May 2011, 07:51 AM   #999
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Massimo, I believe it is right to delay HT. Also, a slow rise-time is helpful to prevent large turn-ON current pulses.

This question can cause many arguments! But I think the comments made by [ Hans van der Weyer [Philips thermionic tube division], about the risk of increased grid current, is the most powerful evidence.

http://www.chiark.greenend.org.uk/scopes/weyer.txt
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Old 25th May 2011, 08:18 AM   #1000
massimo is offline massimo  Italy
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The problem: I can't delay the HT only, but the rectifier heaters too (as I don't have separate Xfrms). Thus the rectifier tube (#80) is still subject to cathode stripping.
OTOH, using just one switch, I power on some s.s. devices (your regs) that supply voltage (almost) immediately while the HT will follow after a while (the rectifier needs to warm up).
Another idea could be to use a relay driven by a NE555 that connect HT winding CT to gnd after few secs.
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