[Elecraft] OPT1 low volume

[Ward Willats]

I'm still trying to figure out why signals drop when I switch in OPT1 
on my newly-built SSB board for my K2/100. The static goes way down, 
but do do the voices!

Last weekend I discovered rfc2 shorting out to they can of crystal 
X7. When I rewound it that helped some.

Today I rewound T2 and that didn't make any difference at all.

I've been around once with Gary, and I think all the obvious things 
are right. The crystal cans aren't shorted to ground, the caps are 
the right values and aren't shorted by DC either, the diodes are in 
the right way and the voltage checks on the switching network are 
fine.

Gary says there should be a "small but progressive" signal loss 
through the SSB filter. To check this, I tuned to the birdie at the 
bottom of 40 meters, and dragged out the scope.

I set in on a 2mv scale with a 1ms sweep (slow) and used the 
measuring cursors to take an average amplitude. I did AC coupling 
with a 1X probe (so may have been loading things down some). Then I 
shoved a 3 inch leftover component lead into the probe clip so I 
could poke around in the small places.

Here are the numbers, from input to output:

P2 -> T1(2) -> T2(4) -> X1 == ~ 1.75mv

before X2  1.28mv
before X3  1.28mv
before X4  1.28mv
before X5  1.28mv
before X6  1.20mv
before X7  1.20mv

T2(3)      1.20mv
T2(1) --> all the way out to P3  ~1.68mv

I can go around again with Gary -- but before the weekend goes and 
before I tear too much working stuff up, thought I'd throw it out to 
you guys to see if there is anything obviously wrong with these 
numbers or the way I acquired them.

Thanks,

-- Ward