Couple of bullets for yall.
As I'm no RF engineer or even purport to know much about what goes on
inside a tuner, I rely upon service manuals! Wow, I bet most of yall
are saying jeez.
Anyway, equipment that is desirable, meaning non-disposable, have very
good service manuals. Yes, I'm a Golden Era of Audio, Crown & Yamaha
Maven. Their equipment is on a par or even better than the best of
Tek, especially their TOTL from either. Both have developed for the
industry and electronics community several advancements that go beyond
audio.
Anyways again; for Tuners:
I've had to work on analog, digital, and hybrid tuners. Working on
the analog stuff with some of the less performing gear is okay;
however, touch a modern digital tuner or Golden Age hybrid, you're in
for a nightmare.
Two of my tuners have analog tuning sections but motorized digital
presets! A wonder to see work, and work every time. Get any of the
alignment off and they go beserk! I use a Sencore SG80 and borrowed
distortion meter. The SG80 is wildly accurate, accurate to the
significance of my just calibrated by SIMCO DC503A Opt. 01!
Most stuff has power supply probs 'cause of bad caps and occasionally
diodes. Most of the time, the stuffs gonna work and be spot on or not
going to work. Occassionally, ya wonder why some stuffs just
performing as you've expected. Well, break out the great gear and get
to work!
I found that a bunch of stuff was off. Did I know or care what was
going on behind the scenes? Yes and know. I'd like to know later,
but wanted my distance stations to come on in! I wanted my amplifier
to stop getting a bit warmer than hot on one side--thermally both
sides were wildly different. Good thing, no oscillations!
GREAT manuals! Just followed the directions along with the equipment
recommendations just like the Tek manuals. Turned out the amplifier
(had two that I sold) was tampered with badly. All I had to do was
get the DC Balance and other stuff back in adjustment. The screws had
been removed except a few for the cover.
Say it like this; those amplifiers, Yamaha M-2 examples cost $1200 new
in 1979--1982! That's $5000 in today's money. Funny thing is, if ya
want an amplifier with those current reserves, continuous power
output, and protection, ya still gotta spend that amount!
This great gear for testing isn't cheap; however, the best gear
demands the best equipment. Cheap stuff (non-digital) won't push the
envelop. The Crown and Yamaha stuff does push the envelop and is well
worth every dime spent on proper equipment. If ya don't, especially
in the tuning world, ya just will be disappointed! Man, some of those
digital tuners have reeeeaaaaaaaallllyyyy low distortion figures!
That's why I had to borrow a distortion meter!
Now my dial calibration is spot on the one that was working okay,
while the other is spot on after looking great but performing
crappily. Go figure.
Later.
