Simplex 35- PR 1014 Threading Lamp Power Supply Question

[Bill Duelly]

Hi All! Quite awhile since I posted, but need help on this... I inherited a Simplex PR 1014 around 2014 and have been very happy running and it has been behaving fine. What I never got around to setting up for it was the framing and door lamp. I tested the circuit with a 9V battery and all lights lit (dimly though). Id like to have something more permanent and brighter than that 9V and went to the transformer, which I still had, which has the following on it: "P-3144 Freed Xmfr. P/N 24650". I tested both sides and one of the side has an open circuit, so I am presuming it's bad. I have tried internet searches and come up empty handed as to type, ratings, new compatible version, etc. I had also purchased a 12V 2A DC power supply, with screw down terminals, that did NOT light them up. When I put the meter on it, it looked like the voltage drops from 12v, w/ no circuit to less than 1V connected to the bulbs. No light at all from them. Any ideas what I can do to power this? Many thanks in advance for responses.

[Steve Guttag]

First off, you want a 6.3V filament transformer. The standard lamps were #55 and wired all in parallel. The maximum number of lamps was 4 (framing, via door switch, door lamps (2), via its own switch, and upper magazine). I see in one place that an Eiko #55 draws .41A...with a 4 lamp maximum that is 1.64A at 6.3VAC, you get 10.33W. You need a 120 to 6.3 filament transformer with, at least a 10.3W capability. My notes show that Strong was supplying a 5V version (probably so the lamps would last longer since they didn't need to be so bright and allow for higher primary voltages than 117VAC) and with a 3A capability. Stancor model P-6467. The 6.3V version was the P-6466 (those are the Stancor models, not Simplex "P" numbers). You'll find that the 6.3V is going to be easier/cheaper to find than the 5.0V one. Naturally, if you are not going to have the upper magazine, you can drop the requirements a little.

Also, do yourself a favor and put a fuse on it so when a wire gets pinched, or touched around the spot sight box cover where the door switch is, you pop the fuse, not the transformer. Something in the ⅛ - 1/4A on the primary should do it.

[Bill Duelly]

Steve, yes you live up to your title of Film God....Not even 3 hours after posting, you have the answer (and then some!) MANY THANKS! I see some 6467's out there and am mulling options. I like the idea of a touch dimmer to save bulbs, vs having to change more often. I double checked and yes I have the 55's. Just one minor question on the transformer, as all I see are pics of them and no info sheets....Which side uses the 2 black wires and which use the blue & yellow? Also great idea about the fuse! I'll try to get to my local Radio Shack and get one of those pieces (YES there is still a Radio Shack in New Holland, PA!)

[Steve Guttag]

The black wires will be the primary side. Also, you'll find that they have a center-tap on the secondary side (the one with the yellow stripe going through it). I seem to recall that the secondary had red wires but regardless...the one with 3-wires will be the secondary. Plus, the paper wrapping of the transformer windings normally is labeled too.

[Randy Stankey]

... Not even 3 hours after posting, you have the answer...

I think his record is just a little over fifteen minutes.

[Bill Duelly]

Ok. Cleared up and confused. Secondary tap? What is that for as I only will need 2 wires…. I’ve seen pix of this transformer with both 3 and 2 outputs. I purchased one with what appears to be 2 wires, yellow and blue…..

[Bill Duelly]

Look what the postman just brought. Unfortunately off to work but tonight’s project!

[Tony Bandiera Jr]

Ok. Cleared up and confused. Secondary tap? What is that for as I only will need 2 wires…. I’ve seen pix of this transformer with both 3 and 2 outputs. I purchased one with what appears to be 2 wires, yellow and blue…..

A tap is used to provide more than one voltage from a single coil of windings. A center tap will be half of the total voltage as referenced to either outside (coil ends) lead, example a 12.6 v center tap transformer the tap will give you 6.3v from either end to the tap.

A lot of equipment uses transformers with multiple taps, each providing a specific voltage as referenced to the common (The starting end of the winding) lead.

So, in your case, with the 6.3 v lamps, you'll use the yellow leads and cap off the blue center tap. Also, since that is a 5v transformer, your lamps will be a bit dimmer than normal. You would have needed the P-6466 to get the full 6.3 volts.

[Steve Guttag]

Tony...perhaps...the primary is 117V. Depending on his wall voltage it could be a bit higher. It is a 3A transformer on the secondary...were he is only loading it to just under 1.5A...so, I suspect it will be somewhere between 5 and 6V. That is what was being shipped by Strong for Simplexes. Technically, the #55 lamp is 7V, I believe. There is a range of suitable lamps too. is/was quite popular (it is 6.3 lamp, known for long life and popular in pinball machines). There are LED options in the too. is a brighter lamp.

I suspect that he'll be happy with most any combination.

[Bill Duelly]

SUCCESS!!! Thank you all for your input on this!!

[Steve Guttag]

I didn't see that the software removed my crosshatch in front of the lamp numbers. So, for the cross hatch, I'll use ML (Miniature Lamp)...the standard for Simplex was the ML55. ML47 is a long-life 6.3V lamp and a bright 6.3V lamp is the ML44.