Awesome! Always good when another piece of gear is saved! Sent from my iPhone
On Mar 27, 2017, at 7:34 PM, Jason Perkins via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
New power transistor, and now B+ is spot on and stable. No more wobbles!
-J
On Sun, Mar 26, 2017 at 11:57 PM Jason Perkins <perkins.jason@gmail.com> wrote:
With some extra off-list help from Dave I found that the main power transistor Q213 is leaky.
Now the challenge will be to find one of those, or something that can sub, without having to pay $50 in shipping!
-J
On Sun, Mar 26, 2017 at 4:58 PM, David Gesswein via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
On Sun, Mar 26, 2017 at 04:51:30PM -0400, Jason Perkins via vcf-midatlantic wrote:
After the regulator I measure 61.5 volts DC w/ .35v to .41v of ripple at 60hz. - sounds like it's not regulating much
Reading the manual more, it doesn't use an integrated voltage regulator "The unregulated 65-volts DC from the power supply circuit board enters
the
video circuit board at plug P202, pins 2 and 3. Assume that the Terminal has just been turned on and the output of the +53-volt regulator is at zero volts.
Didn't have time to look at the schematic but if you are reading 61.5V on the 53V output the regulator probably isn't regulating so its not filtering the ripple. Are you able to understand the circuit to see how it should be regulating and that the correct output should be close to 53 volts?
-- Jason Perkins 313 355 0085
-- Jason Perkins 313 355 0085 Sent from my iPhone