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AC-30 TB voltage specs?

6/1/1999 10:11 AM
Benjamin Fargen
AC-30 TB voltage specs?
To all:  
Can someone list the following voltages from a real AC-30 TB that they have worked on? I have never had the opportunity to work on one and all the schematics I have do not include voltages. Thanks for your help!  
1.first and second preamp plate VDC  
2.phase split plates VDC  
3.EL-84 plates and grid VDC  
4.true B+ VDC after the 5AR4  
6/1/1999 2:54 PM

If no-one else gets back by the weekend, email me. I've got to change some tube sockets in mine anyway, so I'll check while it's apart!  
6/1/1999 3:42 PM
Benjamin Fargen

Thanks! I really appreciate it!  
6/1/1999 3:42 PM

The factory schematic in TTAB has all the voltages, and the Weber book has it as well I believe.
6/1/1999 4:16 PM
Benjamin Fargen

I own the Weber book..... but the text is so small and sloppy it is to hard to read what they say.  
6/2/1999 6:10 PM

maybe my copy is clearer.. here ya go:  
PT: 280V 160mA  
B+: 320V (plates)  
Screens:about 320V  
Cathode: 10V @ idle, 12.5 @ 30W output  
PI Plates: 230V  
PI Cathode: 56.5V  
Pre-amp supply: 290V  
Pre-amp plates: 170V  
Top Boost Circuit: (V1a is gain, V1b is CF)  
Supply: 290V  
V1a plate: 180V  
V1a cathode: 1.65V  
V2b plate: 290V  
V2b cathode: 180V
6/2/1999 6:53 PM
Benjamin Fargen

Your awesome!!!!!Thanks a million!!!  

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