[Elecraft] NGEN/XG-2 Project

[Don Wilhelm]

Paul,

I have thought about doing the same thing here, and have not yet done it -
for several reasons, time being a major one (but have since decided not to
do it that way).

I would hesitate to attempt to combine the BNC output jacks because you may
loose the calibrated output of the XG-2.  If you want to do the job
properly, you should use an isolating hybrid combiner which will introduce 6
dB loss in the path.

Really good stiff leads would be required if the 3 position switch for the
XG-2 is re-located, any change in stray capacitance due to lead movement
during operation will result in a frequency shift.

I regard these mini-modules as pieces of test equipment rather than as part
of the ham station (operating position), so I don't mind having one BNC
output for each oscillator because it makes the test setup more controlled.
The XG-1 (and I assume the XG-2 as well) could benefit from the isolation of
a total enclosure.  The last time I tried to use it for measurements on an
open receiver on the workbench, the response with added external attenuation
did not track when the attenuator exceeded 30 dB indicating RF leakage.
Rather than modifying my XG-1, I will be building separate oscillators each
in an RF-tight enclosure for very low level receiver testing.  As it is, the
XG-1 is just too handy for the task it was intended to do, quick and easy
measurements at two output levels, 1 uV and 50 uV, and it does that job just
fine.

As for sources of a 3 position switch, look at Mouser, Circuit Specialists,
DigiKey, Dan's Small Parts, Newark, Jameco, and other suppliers of
electronic parts.

73,
Don W3FPR


> -----Original Message-----
>
> I'm putting a NGEN and an XG-2 in a small project case. Assuming that both
> devices would not be on at the same time, would there be some way
> to couple
> the outputs to a single BNC connector, without using a switch, and without
> degrading the performance of the XG-2?
>
>
>
> Also will I have any problems with stability by extending the
> leads for the
> crystal switch a few inches?
>
>
>
> Also does anyone know of a source for a small three position single gang
> rotary switch to mount on the case to replace the switch on the
> XG-2 board?
>
>