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Discussion Starter · #1 ·
I'm looking at a JUMBO that does not have the remote and I see mention of a jumper required in the DB9 connector where the remote plugs in. There is no jumper installed and I can't find any information on which pins need to be jumpered.

I have a mating connector and a soldering iron, can anyone tell me which pins or send a picture if it might show me?

respectfully,
John
 

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Discussion Starter · #3 ·
Thank-you, that does seem to help.
This unit was dropped sometime before. The corner of the case is broken, one of the buttons is missing it's cap, and the volt meter is destroyed. I have been able to disassemble it and checked all the solder connections. Several of the adjustment pots had the wiper pins broken loose from the circuit card though I can't be sure if it was the fall or my ham-fisted attempt to remove the knobs. The main power transformer is toast, no continuity on the input winding and no voltage on the output. There is a sticker on the transformer:
STEGER 31-002 2
PRI 120V 60HZ
93.10.500
Does anyone have access to Steger part numbering codes? I don't know if the 500 is part number for 500VA and I'm concerned about the output voltage of it should be.
I have tried a 50VA control transformer 120V/24V but I thought that might be a little high for the input to the full wave bridge so I'm using a rheostat to keep the voltage closer to 20V into the bridge.
With the jumper installed and all adjustments at 0 I can get a varying voltage on the red and blue terminals based on the Throttle. I hope to try the accel and decel adjustments tomorrow to see if the output voltage moves as I expect. Then maybe I can try connecting to a loco.
I know the 50VA transformer won't run more than 1 loco but for testing it was on my shelf.

Any more info will be appreciated.

respectfully,
John
 

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Discussion Starter · #5 ·
No fuse visible on the transformer, it is potted and has a small crack with some appearance of varnish previously boiled out.
I believe that it should be no more than 20 VAC to feed into the bridge rectifier. Of course the industrial control transformers I worked with over the years are all 24 VAC.I'll have to go by the supply house and chase them through their catalogs again to see if a 20 VAC secondary is available.

respectfully,
John
 

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It would be an 18 volt transformer ( or less) as 18 times 1.414 is 25.4 volts and then a drop across the diode bridge giving approx 24 volts unregulated DC in the Jumbo. A 20 volt unit could cause problems as the bridge input would be 28.8 volts to the bridge rectifier giving 27 volts unregulated, way to high as my guess.
 

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Discussion Starter · #7 ·
Ok, thanks. I have found a 270VA 18V filament transformer that appears that it would fit in the spot where the original transformer was.
I was able to try the accel, decel, and timer adjustments and I got the expected results.
I also found a similar size voltmeter.
I haven't looked for a switch since it still works and lights the LED, just not the arrow legend.
This thing might be rescueable.
Thanks for being a sounding board.

respectfully,
John
 
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