|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
In Reply to: tube output stage help posted by Raju on September 07, 2003 at 01:12:18:
Hi.The 10H choke will be fine. You could use one of the maplin 50VA trnasformer kits to make the mains transformer, this would be large enough to accomodate all of the secondries the circuit requires on one core.
hope this helps.
Follow Ups:
Hi,Thanks Chris for your help. Am I liable to see a variance in the voltage rail due to the higher resitence of the 10H choke?
Typically I don't suppose a few volts either way matters?
Hi.The B+ current is only 14mA total, so the choke will drop 2V max. This is marginal, and you will find that here in the UK our mains is higher than the european average so your transformer will give a slightly higher output than expected anywat. A few volts either way will have less difference than variation between tubes.
Raju,Just a suggestion... Probably best to measure the A+, B+, C+, etc points after you've put in the 10H choke. Then, you can compensate for plate voltage and idle bias on each of the gain stage tubes---by varying the resistances, if necessary.
This post is made possible by the generous support of people like you and our sponsors: