Now retired I'm trying to become active again.
My TS-520S has not been on for 30 years.
I don't have a variactor ( variable transformer ).

I'd strongly encourage you to ask around, find somebody who has one,
and do the power-up with the variable-voltage transformer. Take your
time - ease the voltage up from zerch to nominal over a period of a
few minutes.

At the TARC advice was to put a lightbulb in series
to take the surge. Should I use a high resistance
( low wattage ) bulb or vice versa ?

If you do this, do the former... low-wattage. You want to power up
the rig *slowly*, so that the dielectrics in the electrolytic
capacitors have a chance to re-form gently. The lower the wattage of
the bulb (the higher the resistance) the longer it'll take to charge
the power supply fully and the lower the final voltage will be.

You could do it in stages. Wire up a standard light-bulb socket in
series with a power cord for the rig. Start out with a 5-watt bulb,
power up, let the rig sit for a few minutes, power down again, switch
to a 25-watt bulb, repeat the process again... then go to a 100-watt
bulb, then a 200-watt bulb.

This approach isn't as effective, or as controllable, as using a
Variac or similar variable-voltage transformer. The bulb's resistance
will be low when it's cold, and will rise when it heats up... so it
won't limit the initial inrush current all that effectively.

Would this be as good as a simple L-C network ?
Somebody said just plug it in.

It might easily go BOOM if you do. If it's been sitting around
un-powered for 30 years, the dielectic oxide layer in the power supply
caps may have thinned and developed pinholes... hitting it with full
mains voltage and no current limiting could result in a sudden short
circuit inside the caps. They're quite spectacular when they blow...
messy, though.

Are there any other
ideas ?

Negative-temperature-coefficient resistor instead of a light bulb?
These are used as inrush suppressors in switching power supplies...
their initial resistance is high when they're cold, and drops when
they warm up.

Borrowing the use of a Variac for half an hour is still a better way
to do it, I think.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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