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Old 2nd Jun 2010, 4:50 pm   #2
wireful3
Retired Dormant Member
 
Join Date: Sep 2003
Location: Bristol, UK.
Posts: 808
Default Re: Osram Four New Music Magnet

I can't remember the specific voltages quoted for this set but The HT is almost certainly 120v. The SG is about 90v but 60v might also be OK. The GB will depend on the valve used but will probably be round about -3v or -1.5 volts. The original grid bias batteries had taps at 1.5 volt steps and I think the intention was to use trial and error. It would be less than 9v as this was the usual max voltage of the batteries.

The 9v batteries might even be later than the Music magnet, because it was normally used with a variable Mu valve as a volume control (RF gain)
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