On Mon, Apr 4, 2022 at 07:23 PM, Mark Vincent wrote:
diyguitarist,
The two gentlemen, Michael L. and Ed B., are absolutely right. Others will
have great advice as the post. I have the 453 and 4/A series I have restored.
I did restuff the main filters, replaced the 1mfd axial decoupling with film
and a couple of tantalums of higher capacitance to give higher filtering, used
Nichicon UHE 220mfd 25V as decoupling for the two 12V supplies and higher
capacitance for the 75V decoupling. I did replace carbons with 1% types and
raised the wattage of some resistors. The triggering was adjusted as well as
other circuits to get it right after resistor and condenser replacement. I did
read that raising the resistors in the high voltage area to 1W should be done.
I did this in mine. I did use 1% types as that is the tolerance I use. One
thing I do suggest is to oil set screws and shafts. Experience taught me this.
What you did to replace the trigger lamp with an LED is fine. I did this in
one of mine with a 4300 ohm resistor to the white LED because the lamp was
burned out. My LED is about 2,5mA operating and is bright enough. I got mine
cleaned up and cleaned the crt because I wanted mine to look as nice as
possible. If you want any further help, we are here. What I said I did is what
I did to mine. You do what you want with yours.
Mark
Since it's a unit from 1969 (serial #37389) I have considered committing re-cappicide. I really don't like the design of the whole can capacitor arrangement. It appears to me that you have to dismantle half the scope in order to replace those. That's not a road that I really want to go down if I can help it.
diyguitarist