The Family DuMont

[CaryLee]

The SAMS calls for a 1200 ohm 25 watt rheostat...

Surplus Sales has a 1000 ohm 25 watt, left side of the page on link below..for $8..would that be close enough?

http://www.surplussales.com/Potentio...sRheost-4.html

[Phil Nelson]

Originally Posted by CaryLee

Surplus Sales has a 1000 ohm 25 watt, left side of the page on link below..for $8..would that be close enough?[/url]

That's exactly what I installed in my RA-113.



The shaft was too long, so I cut it down and filed a flat area to fit the knob.

Phil Nelson

[CaryLee]

Outstanding! Thanks for the input..I'll get a couple of those rheostats ordered so I have a spare around.

Restrung the tuner dial tonight. The list of "to-do's" gets shorter!

I called my mother a couple nights ago and told her "the DuMont lives!". She remembered when I hefted that sucker out of grandma's house and into her van, by myself, about 25 years ago. She used to watch that TV when she was a little girl. When she comes out to New Mexico for a visit later this year, it looks like she'll be able to watch it again. That's pretty cool.

[earlyfilm]

Originally Posted by CaryLee

I'll get a couple of those rheostats ordered so I have a spare around.

Cary, if it were me, I'd also purchase one of the $1.25 10 watt 200 ohm resistors that Nebr Surplus has and add it on to one end of the pot. Yes, I know the new pot is within 20% of the original, but that pot and the focus coil are in a divider network in your power supply. I suspect that with both the new pot and that resistor in place your B+ supply voltages will be better behaved, and this could possibly improve your weak reception.

Jas

[CaryLee]

Originally Posted by earlyfilm

Cary, if it were me, I'd also purchase one of the $1.25 10 watt 200 ohm resistors that Nebr Surplus has and add it on to one end of the pot. Yes, I know the new pot is within 20% of the original, but that pot and the focus coil are in a divider network in your power supply. I suspect that with both the new pot and that resistor in place your B+ supply voltages will be better behaved, and this could possibly improve your weak reception.

Jas

Thank you for the suggestion. I went ahead and ordered two rheostats and two resistors so I'd have a spare set. Does it matter which side of the pot I put the resistor on?

According to the tracking number, the package from Surplus Sales is on schedule to arrive tomorrow. I'm looking forward to install!

[earlyfilm]

Originally Posted by CaryLee

Does it matter which side of the pot I put the resistor on?

Whichever side puts the best focus nearest to the center of the pot.

With the non-open pot in the bleader circuit, it will shift some of the various "B" voltages and you may have to tweak some of the adjustments, including the ion trap.

J.

[CaryLee]

Originally Posted by earlyfilm

Whichever side puts the best focus nearest to the center of the pot.

With the non-open pot in the bleader circuit, it will shift some of the various "B" voltages and you may have to tweak some of the adjustments, including the ion trap.

J.

Well, I had a 50/50 chance of getting the extra 200 ohm resistor on the "right" side of the focus pot...and I got it wrong. Best focus is now with adjustment turned all the way to the left. Pulled chassis to move 200 ohm resistor to other side of pot.

I did get a MUCH better picture, though. Eye Tube still very dim. Think it's a bad tube, since I could see faint action looking directly at tube.

As far as the picture goes, a lot of "ghosting", and the top of the screen bends right..I think...I've been looking at the screen in a mirror as I make adjustments out back.

Gonna move resistor and try again. Don't think it's going to change picture quality much, if at all. l