Trying to get an old Bremer-Tully Model 81 radio going for a friend who has had it in his family since new. The problem I'm have is there is not a tube in the Regulator socket and the schematic says "Voltage Regulator" but gives no tube #. Can anyone help me find out what regulator tube it takes (it's 4 pin if that helps). Thanks-Jay

:Trying to get an old Bremer-Tully Model 81 radio going for a friend who has had it in his family since new. The problem I'm have is there is not a tube in the Regulator socket and the schematic says "Voltage Regulator" but gives no tube #. Can anyone help me find out what regulator tube it takes (it's 4 pin if that helps). Thanks-Jay
:
What is your tube line up otherwise?

All the Best,

Bill Grimm

Dah, sorry, I'm a little slow today. I found the schematic, on this site of all places.

You don't really have a voltage regulator tube in this set, even though it is labeled as such on one of the drawings. Terminology wasn't really standardized in 1933. The tube in question is a balast tube.
The balast tube in your case is little more than a light bulb.
I would consider using a light bulb in its place. Pull out all the tubes. Start with a 100 watt bulb in place of the balast tube. Measure the voltage on the fat prong connections in its socket. If they read a little more than 5 volts AC(I estimate around 6 to 8 volts), then a 100 watt bulb will do. If the voltage seems too high, then go down in wattage until you get the 5 volts.

The schmatic indicates that the balast tube should drop the voltage to 77 volts. It is a little confusing. The schematic is http://www.nostalgiaair.org/PagesByModel/398/M0002398.pdf.

Best Regards,

Bill Grimm

:Dah, sorry, I'm a little slow today. I found the schematic, on this site of all places.
:
:You don't really have a voltage regulator tube in this set, even though it is labeled as such on one of the drawings. Terminology wasn't really standardized in 1933. The tube in question is a balast tube.
: The balast tube in your case is little more than a light bulb.
: I would consider using a light bulb in its place. Pull out all the tubes. Start with a 100 watt bulb in place of the balast tube. Measure the voltage on the fat prong connections in its socket. If they read a little more than 5 volts AC(I estimate around 6 to 8 volts), then a 100 watt bulb will do. If the voltage seems too high, then go down in wattage until you get the 5 volts.
:
: The schmatic indicates that the balast tube should drop the voltage to 77 volts. It is a little confusing. The schematic is http://www.nostalgiaair.org/PagesByModel/398/M0002398.pdf.
:
:Best Regards,
:
:Bill Grimm
:

My ballast tube book shows a 105 tube for a model 81-A, dropping 30V @ 1050ma.
Carl T

::Dah, sorry, I'm a little slow today. I found the schematic, on this site of all places.
::
::You don't really have a voltage regulator tube in this set, even though it is labeled as such on one of the drawings. Terminology wasn't really standardized in 1933. The tube in question is a balast tube.
:: The balast tube in your case is little more than a light bulb.
:: I would consider using a light bulb in its place. Pull out all the tubes. Start with a 100 watt bulb in place of the balast tube. Measure the voltage on the fat prong connections in its socket. If they read a little more than 5 volts AC(I estimate around 6 to 8 volts), then a 100 watt bulb will do. If the voltage seems too high, then go down in wattage until you get the 5 volts.
::
:: The schmatic indicates that the balast tube should drop the voltage to 77 volts. It is a little confusing. The schematic is http://www.nostalgiaair.org/PagesByModel/398/M0002398.pdf.
::
::Best Regards,
::
::Bill Grimm
::
:

Should be a way to figure this with math.

120 VAC 60 hertz ... Drop to 77 @ 1.50 amps ..

According to my imprecise miscalculations That would be

41 Ohms @ 45.2 Watts ? Or 33.70 MFD AC capacitor ??

I found that a 300 watt incandescent light bulb works as a ballast "tube" for this set. I get 2.4 volts AC on all tube filaments, operating voltages are in spec. I had to gut an old UX 4-pin base and install the guts from an old lamp socket into it. The bulb glows bright orange...

That's being inventive alright. Halogen projector lamps come in all different voltage and watts. An EYK-300 is one possibility. These are now old school stuff and should be plentiful and cheap.