Milan,
Thanks for this explanation, it makes sense to me. I've noticed that component values that were common 50 years ago (or more) are not common today, so the reverse is also understandable. It was also suggested that this was an attempt to make a higher wattage part than was either available, or than would fit in the space provided. The resistors are bigger than 1/4 W ones, but the manual only specs them as 1/2 W.
Regardless, they've drifted pretty far out of spec (more than 20%) and will need to be replaced. I've ordered a selection of 1/2 W resistors that should include 7.5 K Ohm parts.
-- Jeff Dutky
