[ARC5] AC Power Supplies

[Brian]

Hello Dave,
Very nicely made.
My first concern is for the stress on the HT secondary winding at start-up, with direct feed to 94 uF of filtering. For trannie longevity, I would put small resistors between both filter caps and one between the rectifier and the first filter cap. 100 Ohm each will only drop the output HT Voltage 8 V. For a commercial example, Tektronix did this with all their solid-state, linear power supplies on their 500-series of CROs.
My second concern is those 20+ year old capacitors; electrolytic capacitors like running close to their rated Voltage. So, if they’re falling over – low C, high ESR – I’ld replace them with ones rated at 180 to 220 Vdc wkg.
Dave Stinson, AB5S and I – and many others - will confirm that Command receivers work very well with 160 Vdc HT.
Your 22k bleeder is a very good choice – hardly affects the output current available, and gives a 1/e Voltage drop every 2 s. Safe.
73 de Brian, VK2GCE.

On Tuesday, December 27, 2016 12:53 PM, you showed:

Here are some photos of a power supply I built on a DM-10A base 20+ years ago.  I don't recall where the transformer came from but it had both 6.3 and 24 volt filament windings so I allowed for both.  Cap is a dual section 47 uF @ 400 VDC connected in parallel.  Full wave bridge with a 22K bleeder resistor.  Produces 165 VDC @ 40 mA.

There is a PC-8417 transformer with similar filament specs and 220-0-220V on eBay now - item 371821125244 (toober is the seller).
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