[time-nuts] Re: 5065A - A15 (PSU)

[paul swed]

Ulf pretty funny. I knew someone had developed a replacement integrator for
the 5065a. It was indeed you in 2017. Small world.
With respect to the inverter I will need to listen to my unit. I do not
recall anything very loud. But loud is different for every person. Like the
idea of eliminating the -20 inverter but that really means changing A3 and
A7 significantly. I had not realized that the DC bias to the photocell
actually comes from the input opamps output on A7. Something to learn every
day.
Regards
Paul
WB8TSL

On Thu, Dec 2, 2021 at 7:11 PM Shawn <comsec at xmtservices.net> wrote:

> Let me second Paul's question.
> I too am interested in the purchase of 2 of these boards and am happy
> to contribute funds in the advancement of this project.
> Shawn
>
> On Thu, 2021-12-02 at 15:09 -0500, paul swed wrote:
> > Ulf I would have replied off list. Are you intending to sell blank
> > PCBs?I was recently thinking about the same thing as I watched the
> > cfld move abit.I know there is also a earlier thread on this subject
> > 3-5 years ago.RegardsPaulWB8TSL
> > On Thu, Dec 2, 2021 at 11:15 AM Ulf Kylenfall via time-nuts <
> > time-nuts at lists.febo.com> wrote:
> > > Since the A15 regulator board is mentioned...
> > > I recently decided to try to improve the Voltage Regulator board
> > > A15inorder to use a better voltage reference than CR5 (9V) and
> > > alsosee if Icould reduce the drift and noise of the Magnetic Field
> > > winding.After some experimenting, I am reasonable satisfied.
> > > The board has been completely redesigned.
> > > The drift and noise of the +20V is reduced. Thermal driftcompared
> > > to theoriginal design from the MagFieldcircuitry is also reduced
> > > significally.
> > > Modern thru-hole components are used facilitating manual assembly.A
> > > total of 10 PCB's have been ordered (Double side, solder
> > > masksilkscreen, plated holes etc.) but I did not opt for over-
> > > nightdelivery, so itwill be another couple of weeks for them to
> > > arrive.I will assemble a board for myself and, unless covid makes
> > > itimpossible,take the 5065A to my former employer and evaluatethe
> > > performance usingstandards available.If it performs well, the
> > > design will be placed into "public domain".Best RegardsUlf
> > > KylenfallSM6GXV
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