VCCA Home Forums TECHNICAL - GENERAL Radios, Tools, Accessories 1934 Radio "Glow Bar" Needed...(?)

Hello All! I have a 1934 Chevrolet Radio (the one with the separate speaker and has 5 tubes). A friend of mine, gave this radio to a neighbour. He had his own TV and Radio repair shop for more than 22 years. He checked it over but said he could not test it because the "Glow Bar" is not working. He said he does not have any in his possesion. The piece (according to my friend), looks like a brass tube with 2 connectors off of each end.

I have looked on Ebay for this part and have found nothing. Can you radio guys tell me if these are available or if this is what you actually call this part?

Thanks,
Garry.

Glow Bar???? I must have the cheap model, no glow bar.

You would be hard pressed to need a part for a 1934 and me not have it. I do NOT sell parts, however I can restore your Chevrolet radio.



PS: I bet he means the vibrator?????

Thanks for your reply, Ray. My friend said that when his neighbour put power to radio, only two tubes will light up. The power will not go to the other tubes because of this part. Is that the vibrator? I am unable to talk with this retired radio repairman directly. He is in his late 80's and is only looking at this radio as a favour to my friend. So the information I get, is second hand. You would not believe what comes up on Ebay, when you type in "Glow Bar"....

Garry.

It is fruitless for me to speculate as to the problem. The vibrator has no direct contact to the A+ circuit.

If he is a repairman he should understand the A+ and B+ circuits.

The Glowbar is described on the circuit for radio chevrolet radio "601038"

as a voltage regulator 1 watt resistor ( r19 )
part number 1208643.
It is a resistor on the output side of the vibrator's power transformer.

It varies the voltage output by as the tubes warm up.
You may be able to subsitute a ceramic or other resistor in its place.

And it is actually spelt "GLOBAR"

Thank you Ray and Jack. I will get the radio back from this gentleman this weekend. I'll try and post a picture of this part. Thanks Jack for the proper spelling! No wonder my search on Ebay turned up nothing! I will also post the model number once I get the radio back.

The Model number of the radio is: 601038. The Globar is a brand name for a special resister and was removed in later Radio Service Bulletins. This special resister was used in household table top radios to reduce the shock of 120 Volts AC across the heater circuit. As the resister warmed up it slowly allowed the full voltage. The heaters were in a series circuit in the smaller sets.

You may be able to replace it with a resistor from Kanthal Globar
as they make modern non inductive ceramic resistors , which act as current smoothers , if you can find a distibuter that sells them, otherwise delete and install a jumper wire.
check this link:

http://www.cesiwid.com/ec/src/axial.pdf

Garry,

Further to your description of the fault with the radio.

"Only 2 tubes light up"

The tubes light up due to heaters or filaments within the tubes.This gives the glow or light in the Tubes.
The filaments are showing as pins 3 & 4 on the circuit diagram.
A continuity check between these two pins should show they are connected inside the tube.

The filaments are all fed 6 volts to one pin on the tube, and grounded on the other pin of the tube. this is the voltage from the car battery at 6 volts. So no continuity of the heaters in just one tube and the radio stops.

Further to the Globar. The globar is in the high tension(voltage)(approx 180-200 volts) of the radio which connects to the "plate" or anode of the tubes, and is not connected in any way to the filaments, so would not stop the other tubes from lighting.

Other problems encountered in old radios are carbon resistors going out of spec. paper capacitors "leaking"(voltage internally). Electrolytic capacitors "leaking" and not filtering out ripple in the high tension voltage, open circuit coils and tranformers,,, to start with.

When you get your radio back , start with checking the heaters on the tubes that dont glow.

Lots of fun.!!

Thanks again Ray and Jack! I am picking up the radio tomorrow (1 week later than expected). I'll let you both know what I find tomorrow. Until then, Thank you both again.
Garry.