HF Amplifier repair

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Last week I had a slight misfortune with my GI7B valve amplifier. As I was coming to the end of a session in the shack I had made the mistake of operating without the cooling fan on full speed which resulted in a resistor overheating whilst tuning up during a change of band. I ran a bit too much anode current during a tune up which combined with the lack of cooling was too much to get away with.
The followin day, I took a careful approach and inspected the amp thoroughly for any other damage. The resistor, a 2watt 1ohm resistor was easy enough to replace and once I completed the repair and replaced the fuse I was back up and running. Whilst I had the amplifier apart I took the time to clean out the accumulated dust and also got to know exactly how it all functioned. Simple enough and very well constructed.


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