Thanks for mentioning the light show! A friend had a model 19 table that had the panel that hid the power supply removed for some reason. Make a tape and enjoy the light show all over the room.

   Brenda Gentry, KA2IVY

And when it's drawing current, the thyratrons in the REC-30 power supply glow brighter, so it's a really nice light show while you're typing -- https://www.youtube.com/watch?v=fxy2Ifo8Xx0

fwiw i measured mine at 600-700mA at 120vdc with the punch engaged so yeah I'd definitely count on it really needing 1A.

-eric

On 2026-03-03 17:58, E. wrote:

Yeah, while the punch sits there, it draws nothing (so as long as the 14TD isn’t powered on alongside it… usually the two are tied to the same power source)… but when a punch occurs, the amperage very quickly and briefly spikes up to around 1A.  Type as fast as ‘punchingly' possible and you can imagine how many spikes can be had within a short period of time.

On Mar 3, 2026, at 7:49 PM, Johannes Eggers <[email protected]> wrote:

So, with the punch running, does it actually draw 1 Amp ?  That'd be 120 Watts, which seems a lot.  If the printer solenoid takes 60mA at 120V, so 7 Watt, then the 5 punch solenoids would have to draw 3 times as much, each, to get to 100 Watts.

That PSU runs about $200 now, double-yikes !

Thanks for the info.  I'm a little bit wiser now, but I still don't understand what I hear about the 60mA loop current: If I put a 2k resistor in series with a 120VDC supply, then the current will be AT MOST 60mA (if the solenoid shorts out), but if the solenoid is OK, then I'll get LESS than 60mA.  I need to find my Model 15 and measure the coil resistance.

I assume when the punch isn't punching, it draws nothing?

Thanks,

Johannes

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