gregz wrote:
gregz wrote:
Fox's Mercantile wrote:
On 3/21/18 10:45 PM, wrote:
Just meandering thought here, what is the actual line voltage?
You know these old things were made to work on 110, not 125.
And as usual you are wrong.
Per the manual:
http://w140.com/tek_565.pdf
The line voltage can be selected from 110, 117, 124, 220, 234 or
248 vac. 50-60 cycles.
120 normal here, and 125 up in building. I'll check that. I just saw a 500
vdc on power supply diagram. Not sure where that came from.
Thanks
Gregj
500 was changed to 300 vdc in my schematic.
Greg
Been extra cautious with this thing. Been checking everything. Replaced a
VR tube, and moved a lead from VR adjust pot was too close to chassis.
Replaced all 3 10 ohm resistors with wire wounds. Put current sensing LEDs
with drops across each. With hard turn on, the one has a pretty huge
current spike. I think that one was the original problem, pretty sure at
top of 420 volt section. Failure of it may have taken out one on lower
supply, guessing.
This scope may be replacing one in research setup, that uses external
connections, and an extra mod for a sawtooth output.
Years ago, another 565 from the same lab was mounted at the top of a rack
with wheels. I was pulling out a big strip chart recorder near the bottom.
The rack started tilting forward, and strip chart extending. I decided to
move out bumping into table, and loud crash. Was not pretty. They kept
using that wheeled rack, but put lead weights in bottom.
Greg