[GreenKeys] TU-170 update

[John, W9DDD]

It arrived yesterday.  Looks well built, maybe factory?  The mystery 
switch is single pole 3 position (center off). The wiring seems to match 
the rest.  (I suppose a kit builder could have had left over wire?)  I 
guess I'll have to fire it up to figure out what it does.

The MFE340 current is limited to 60ma, so no need for a external 2k 
resistor.  Didn't need anything more than Ohm's law to figure that out.


Good afternoon all,

I'm expecting a TU-170 to arrive here Wednesday.  I managed to find a 
copy of the manual on-line.  So I'm checking what the connections will 
be and I'm a bit confused about the loop supply connections.

I appears to me that they expect a loop current setting resistor 
external to the TU-170, but I don't see that referenced any where in the 
manual.  It doesn't appear to me that MJE340 is operated in a current 
limiting mode, but then I took that course last century and forgotten 
anything past Ohm's law.

-- 
John, W9DDD