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Dial Lamp Reference
9/6/2002 6:32:52 PMJoe Miller
I have a radio with a 35Z5 rectifier...the dial lamps are in parallel with half of the filament on the 35Z5. Riders calls for a Mazda type 1490 lamp but I can't find any reference to the specs...Someone before me had placed new lamps (two in series with the 35Z5 filament) but I think they are the wrong size because the blow the filament in the 35Z5..Is there a reference out there anywhere so I can figure out what to substitute with?
9/6/2002 8:42:57 PMNorm Leal
Hi Joe

Lamp 1490 is rated 3.2 volts @ .16 amps. Normally a #47 lamp would be used, 6.3 volts @ .15 amps. Since your radio has two in series a lower voltage lamp is needed.

The lamp wouldn't blow your 35Z5 filament. Most likely it's being blown by shorted electrolytic filter caps. The lamp & a section of 35Z5 filament are in series with power to the plate of your rectifier. If excessive B+ current is drawn the filament will open.

Norm

:I have a radio with a 35Z5 rectifier...the dial lamps are in parallel with half of the filament on the 35Z5. Riders calls for a Mazda type 1490 lamp but I can't find any reference to the specs...Someone before me had placed new lamps (two in series with the 35Z5 filament) but I think they are the wrong size because the blow the filament in the 35Z5..Is there a reference out there anywhere so I can figure out what to substitute with?

10/1/2002 3:29:31 PMWayne Richardson
:Hi Joe
:
: How about a couple of flashlight bulbs? PR-2 or
: similar. The bulb life will be shorter than a reg.PL
: You could place a resistor in series with them if
: needed.
: Wayne
10/1/2002 4:27:18 PMNorm Leal
Hi Wayne

PR lamps can be found with low voltage but they draw higher current. In this radio bulbs are used in series with .15 amp filament tubes. PR2 needs .5 amps and wouldn't light.

Norm

::Hi Joe
::
:: How about a couple of flashlight bulbs? PR-2 or
:: similar. The bulb life will be shorter than a reg.PL
:: You could place a resistor in series with them if
:: needed.
:: Wayne



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