[time-nuts] General Technology Corp model 304b

[Ed Palmer]

My unit has many connections between chassis and circuit grounds, most 
of which look intentional.  There are connections at the 1 MHz and 100 
KHz BNC outputs (the 5 MHz output is transformer coupled).  There's also 
a connection at an SMC connector from the multiplier to the SRD final 
amplifier.  And a connection between the lamp oscillator ground and the 
shell of the physics package.  There's a suspicious connection in the 
physics package that I'm checking out.  It connects the ground for the 
photocell preamp to the ground for the SRD.  Seems rather odd.

Ed


On 4/29/2012 10:12 PM, Don Latham wrote:
> A first-class engineered unit will have a single point where the chassis
> and circuit grounds tie together, Sometimes it's a panel, where the i/o
> connectors are coaxial. I've fixed units with good engineering and
> sloppy construction where accidental extra common points have caused
> problems.
>
>> The bottom pin (pin B) is connected to circuit ground which is connected
>> to chassis ground on my unit and the schematic confirms it.  That could
>> be why you have to ground that pin to make your unit work.  There
>> appears to be a broken or missing ground somewhere in your unit.