24-03-2018, 01:15 PM
(This post was last modified: 24-03-2018, 01:18 PM by Murphyv310.)
Absolutely agree.
Snag is that some sets are on the "edge" and this problem can show up.
The worst set was the Murphy V659 and eventually after two line output transformers the 6/30L2 line multivibrator cathode resistor was found to be 10% high, just at the limit of spec, replacing this tidied up the drive waveform and reduced the foldover, now I only see half the castleations on left being distorted on the worst aurora. Its not a big problem by any means, took long enough though to find the issue on this particular set and overlooked as the component was just in spec.
When I looked before at this there was only marginal differences between individual waveforms, no doubt enough though to be seen on some sets.
Snag is that some sets are on the "edge" and this problem can show up.
The worst set was the Murphy V659 and eventually after two line output transformers the 6/30L2 line multivibrator cathode resistor was found to be 10% high, just at the limit of spec, replacing this tidied up the drive waveform and reduced the foldover, now I only see half the castleations on left being distorted on the worst aurora. Its not a big problem by any means, took long enough though to find the issue on this particular set and overlooked as the component was just in spec.
When I looked before at this there was only marginal differences between individual waveforms, no doubt enough though to be seen on some sets.
