[GreenKeys] tuning scope

[WB6BLV]

Jim I can send you a schematic and parts list for
a tuning scope you can assemble from scratch or
using a gutted scope for the deflection amps and
power supply...also have diagram for solid stating;
Be sure you do NOT use separate tuned circuits
in the scope since you will then NOT be getting an
exact representation of what tones the TU is receiving.
Finally, I also have a schematic for an 'Audio Frequency
Spectrum Analyzer' that displays the tones as vertical
pips on a horizontal line, which is marked for frequency
from right to left.  Can send as attachment to off-list
email addy.

I have built and used all of these.  The 1EP11 still shows
up from time to time, but I much prefer the 2AP1 or the
3BP1.  I usually have no difficulty finding those on the
auction site.  There are fifteen 3DP1s here which were
designed for circular sweep and have a PDA pin right in
the center of the face...these will work if you don't mind
the metal pin sticking out (and you insulate the connection so 
you don't toast  you tacos on the post-deflection anode high
voltage.  If you are THAT brave and desperate, you may
have a 3DP1 for postage.  The AFSA unit above can be
calibrated in various log and linear display formats and will
show alternating pips for mark and space, or it will show
the tones for SSTV or FAX.

It is simple to pick off the mark and space voltages in the ST-6
from the anode side of the two '+/+' diodes.

John
WB6BLV at inreach.com