14-10-2019, 02:15 PM
(13-10-2019, 08:44 AM)Murphyv310 Wrote: They can run quite warm, it depends on many factors like the design of the circuitry and the load on the transformer, even an open circuit on one half of the HT rectifier can make the transformer run too warm.
Can you measure the actual temperature after an hours running?
Hi Trevor,
Finally got to spend an hour in the office listening to the radio. The tuner transformer temperature is now 38 C, ambient is 16 C
Seems reasonable but not low.
The amplifier transformer is at 31 C, I think most of the heat there is by radiation from the KT66s
I'll 'scope the HT ripple to check both halves of the rectifier are working.
Kind regards, David.
