Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2

Don't think you'll find one. What you can do is disconnect the power line and pilot lamp wire from pin 2 of the 35Z5. Then place a 40-50 ohm resistor (I prefer 40, but you can try 50) of about 1 or 2 watts in series with the lamp wire and power wire (connected together) and pin 2 of the 35Z5. If you want, use a wire wound 5 or 10 watt resistor. This is best. Then use #47 bulbs.

To get something a little more realistic that is like the 35Z5 ballast filament, what I have done is use a tube in place of the resistor. The tube will warm up more and will change in resistance more. The resistance will be much lower at cold start-up, putting less stress on the bulbs. I think the 6AT6 uses a .15 ampere filament, but I'm not sure. I know the 6C4 does. Both are 7 pin miniatures that will fit inside the chassis. Solder two wires to the filament pins. Wrap all of the pins with friction tape (cloth electrical tape found at your hardware). Do not use plastic tape. It will come off. Another option is to use the ballast filament (small filament) of the 35W4, which is electrically equivilant to the 35Z5, but is a 7 pin miniature and will fit under the chassis. Again use friction tape around the pins. I forgot which pins are for the ballast filament on the 35W4. My tube manual is wrong, so I have to check it physically on my tube tester. I have to go to class right now, so I'll let you know later.

Thomas

Just a note: I own the 66X5, and I've looked all over for the 1490 lamps (or an equivilant). I can't find any. They're listed in my Radio Tube Manual, an inexpensive gray book put out by www.tubesandmore.com that covers early tube types, but www.tubesandmore.com and just about everywhere else does not sell them. If you use a higher amperage bulb (say 3 volts at .25 or .35 amperes), they will not glow brightly at all. You must use a .15 ampere bulb with the 35Z5, so the only way I found to make this all work is to add that resistor or tube. I've used both methods and both work well. I kind of like the tube method better than the resistor, but honestly both work very well.

Thomas

If you use the ballast filament of the 35W4, pin 4 begins the ballast and pin 6 ends it (and continues to the main filament which ends on pin 3).

Thomas

:Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2- the 1490 is available at 2 places. bulbdirect.com and atlantalightbulbs.com. I just bought a box of 10 for $7.70.

::Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2- the 1490 is available at 2 places. bulbdirect.com and atlantalightbulbs.com. I just bought a box of 10 for $7.70.

10 for $ 7.70! Way better price than the two sites I listed.

Ken

Thats was the price, including shipping from bulbdirect.com. the only down side was they are made in china.

Hi John

Check here:

www.topbulb.com

www.vacuumtubesinc.com

Ken

:Hi John
:
:Check here:
:
:www.topbulb.com
:
:www.vacuumtubesinc.com
:
:Ken
:
:Lots of options! Thanks to all for the good info. John
:
:

Hmm...now I know where to go for 3.2 volt bulbs!

T.D.

http://www.donsbulbs.com/cgi-bin/r/b.pl/1490.html

:Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2

:http://www.donsbulbs.com/cgi-bin/r/b.pl/1490.html
:
::Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2

Try here - http://www.atlantalightbulbs.com/index.html

They have EVERYTHING!! However, a $25 minimum order.

Mike

::http://www.donsbulbs.com/cgi-bin/r/b.pl/1490.html
::
:::Does anyone know of a source for 3.2 volt dial lamps for an RCA 66x2
Bulb Direct (http://www.bulbdirect.com/catalog.asp?prodid=408653&showprevnext=1) has them for 0.60 each. IIRC, no minimum order, either.

73
Bob WA2UEH