[ARC5] Receiver Power Supply

[Ben Hall]

On 4/29/2015 4:11 PM, Mike Hanz wrote:
> that  a variable supply might be a good thing.  For the one or two
> people on the planet who might be interested, I have been fiddling with
> an idea that provides at least a modicum of flexibility, and combines it
> with a way to use your old dynamotor hulks.  It is still a work in
> progress, but such as it is at the moment is at
> http://aafradio.org/garajmahal/virtual_armature.html

Hi Mike and list,

I guess I'm one of the "one or two people" as I'm interested.  ;)

Got a schematic you wouldn't mind sharing?

Some time ago, I wanted to run my BC-221 frequency standard from 
batteries like it would have "way back when."  Instead of making up a 
battery pack with the appropriate number of cells in series to get the 
voltages needed...I set out to build a high voltage DC-to-DC converter 
using National's WebBench online design tool.

I don't recall the DC-DC controller I choose, but I quickly found out 
that the design generated by WebBench wouldn't work with the MOSFET 
suggested, as the power dissipation was just too high.  A second version 
used a larger TO-220 case MOSFET which eliminated the dissipation 
issues.  However, testing soon indicated that it couldn't deliver more 
than a few milliamps without going out of regulation.  I never did 
figure out why actual performance was so much different than what 
WebBench predicted.

That led to many months of reading, experimenting, and tinkering with 
DC-DC HV supplies.  I even was winding my own inductors and 
transformers.  In the end...I never got results that I was happy with. 
I sure did come to understand why the SimpleSwitcher series was so 
popular - they just worked!  :)

So I'd really enjoy seeing a schematic of your design if you wouldn't 
mind sharing.

At one point during my experimentation, I was hoping I would get to the 
point where I could design and build an AC-line powered AC-to-DC 
converter of universal design that could replace iron transformers that 
are getting harder to find for inexpensive prices.  That never came to 
fruition...

thanks much and 73,
ben, kd5byb