[time-nuts] Curious, how many t-nuts have 5065A

John Miles john at miles.io
Sat Feb 24 05:02:39 EST 2018

> Hi
> Well, if anybody else is “giving away” 5065’s I’d certainly be willing to
> “accept”
> one :)
> Bob

Be careful what you wish for. :) The unit Pete is talking about is a 1969-era model, in nice overall shape but with the usual bad capacitors on the oven controller board.  The lamp oven winding should be about 50 ohms cold, but is closer to a dead short.  It will take a LOT of work to restore to working condition. 

The failed controller ran long enough to smoke a 1.5-ohm 1W resistor, 1N400-something diode, and eventually the 1A line fuse ( http://www.ke5fx.com/5065A_A11_sm.jpg ).  Needless to say the lamp PCB looks like something out of Fukushima.  It'll need to be rebuilt from scratch after rewinding the heater.

Seriously -- anyone with a 5065A who hasn't checked/replaced the caps on A11, don't let this happen to you.  They aren't making any more of these puppies.  If the caps on that board are original, don't bother to check them, just replace them, as Luciano suggests at http://www.timeok.it/hp5065a-corner-3/.  No need for exotic parts, just put in whatever you have that is somewhere close to the original values.  

Not a bad idea to verify the ESR of the new parts you're installing as well.

-- john, KE5FX
Miles Design LLC

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